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Section 2: Upper Limb
Figure 5
Rochester, MN.)
Atlas of Amputations and Limb Deciencies, Fourth Edition © 2016 American Academy of Orthopaedic Surgeons
392
Image of the brachial plexus physical examination form. (Courtesy of the Mayo Foundation for Medical Education and Research,
Chapter 32: Brachial Plexus Injuries
Figure 6
with Horner syndrome, which consists of miosis, ptosis, and anhidrosis. (Courtesy of the
Mayo Foundation for Medical Education and
Research, Rochester, MN.)
Clinical photograph of a patient
varied degrees of injury. Otherwise, the
location of the BPI can be described in
reference to the clavicle as supraclavicular (root and trunk), retroclavicular
(division), and infraclavicular (cords
and terminal branches). Similarly, the
location of injury relative to the DRG
can be expressed as preganglionic or
postganglionic.
BPIs usually occur at sites where
the nerve is relatively fixed, restrained
by surrounding structures, or changes
direction. Examples include the suprascapular nerve within the suprascapular
notch, the axillary nerve within the
quadrilateral space, or the musculocutaneous nerve as it penetrates the
coracobrachialis.11 In general, supraclavicular injuries are more common
than infraclavicular injuries. Of the supraclavicular injuries, a panplexus BPI
is the most common injury pattern. In
addition, upper trunk lesions are more
common than lower trunk injuries.
Physical Examination
A thorough physical examination can
aid in the accurate diagnosis of a BPI.
On inspection, any traumatic or surgical
wounds are noted. The resting position
of the hand, wrist, elbow, and shoulder
girdle can help elucidate the dysfunctional motor units. Percussion along the
course of the nerve can elicit paresthesias in the distribution of the nerve root
that can help distinguish between preganglionic and postganglionic injuries.
Pain over a percussed nerve typically
indicates a rupture, whereas lack of pain
Tab le 1
Physical Examination Findings That Suggest
Preganglionic Brachial Plexus Injuries
Clinical Entity Muscles Affected Nerve Spinal Level
Horner syndrome NA T1 sympathetic
Scapular winging Serratus anterior Long thoracic C5-C7
NA Levator scapulae Dorsal scapular C3, C4, C5
NA Rhomboids Dorsal scapular C4, C5
NA Cervical paraspinal Dorsal rami C4-T1
NA = not applicable.
can indicate an avulsion.10 An advancing
Tinel sign suggests a recovering nerve
lesion and should be serially examined
over time.
14
A systematic motor examination
of the entire affected upper extremity
is imperative to localize the BPI (Fig-
ure 5). Motor strength can be graded
based on the modified British Medical
Research Council system, with useful
motor function defined as grade 3 or
higher. To assign grade 3 strength to a
muscle, the muscle unit tested needs to
have motion against gravity in the full
arc of passive range of motion. Grade
3 strength cannot be obtained if active
motion is unequal to passive motion,
no matter how strong the muscle is in
the lesser arc of motion. In addition,
the integrity of cranial nerve XI should
be assessed with strength testing of the
upper, middle, and lower trapezius, because the spinal accessory nerve can
be used as a donor nerve for nerve
transfers or the trapezius tendon can
serve as a donor for shoulder tendon
transfers.
In most cases, upper trunk injury
results in a predictable loss of shoulder
abduction, external rotation, and elbow
flexion. Additional damage to the C7
nerve root in an upper trunk BPI can
be indicated by triceps, pronator teres,
and/or wrist and finger extensor muscle weakness. An isolated lower trunk
injury often manifests as loss of hand
function (intrinsic and extrinsic) with
preserved shoulder and elbow function.
ganglia
In T1 nerve root avulsions, disruption
of the sympathetic outflow to the head
and neck can occur because of the intimate relationship of the sympathetic
ganglion for T1 and the adjacent nerve
root. This can be clinically evident with
Horner syndrome (miosis, ptosis, and
anhidrosis) (Figure 6). Similarly, certain findings on clinical examination
can suggest a preganglionic BPI within
the upper trunk (Table 1).
A comprehensive neurologic examination must be performed to identify
a coexistent spinal cord injury (SCI). A
prevalence of 12% has been reported
for a concomitant SCI in patients with a
BPI.16 Patients with a combined BPI/SCI
who have sustained a preganglionic injury at one or more root levels are more
likely to exhibit Horner syndrome and
phrenic nerve dysfunction than a patient with an isolated BPI. Theoretically,
a shared mechanism of injury results in
a combined SCI/BPI. Therefore, a neurologic examination of the contralateral
upper limbs and bilateral lower limbs
should be performed, including sensory levels and the presence of increased
reflexes or pathologic reflexes.
A vascular examination is performed
because injury to the axillary artery is
not uncommon with infraclavicular BPIs
or in cases of scapulothoracic dissociation. The status of the axillary artery is
also important because the thoracoacromial trunk is a common target vessel
for free-functioning muscle transfers
(FFMTs).
C8-T1
10
© 2016 American Academy of Orthopaedic Surgeons Atlas of Amputations and Limb Deciencies, Fourth Edition
393
Section 2: Upper Limb
Figure 7
and root avulsions. (Courtesy of the Mayo Foundation for Medical Education and Research, Rochester, MN.)
Imaging Studies
After a traumatic injury to the neck or
shoulder girdle, initial imaging studies
should include plain radiographs of the
cervical spine, shoulder (AP and axillary
views), and chest. Spine radiographs are
obtained to rule out any associated cervical spine fractures that could encroach
on the spinal cord and cause an SCI.
Cervical transverse process, spinous
process, and vertebral body fractures
are often associated with a root avulsion
at the same level.10 Shoulder radiographs
are obtained to ensure glenohumeral
joint reduction because loss of deltoid
and rotator cuff muscle tone results in
inferior subluxation of the humeral head
from the glenoid. Chest radiographs are
evaluated for any rib fractures and the
presence of an elevated hemidiaphragm,
which can indicate phrenic nerve palsy.
These findings can deter use of the intercostal nerves and/or the phrenic nerve
as potential donors for nerve transfers.
Clavicle or rib fractures (first or second
rib) can be assessed on shoulder and
chest radiographs and can suggest trauma to the brachial plexus.
The use of CT myelography has
Coronal (A) and axial (B) CT myelograms of the spine show pseudomeningoceles
injury11 (Figure 7). Fine-cut postmyelographic CT has a reported sensitivity
and specificity between 80% and 90%
in the detection of both pseudomeningoceles and the diagnosis of root avul-
13,14,17-19
sions.
However, immediately
after a preganglionic BPI, a hematoma
can be present within the pseudomeningocele that can displace the dye used
for myelography, producing a false-negative result.10 Therefore, CT myelography
should be performed 3 to 4 weeks after
BPI to allow blood clots to disperse and
pseudomeningoceles to fully form.
MRI has some advantages over CT
myelography when evaluating patients
with a BPI.
18,20, 21
CT myelography is limited to visualization of the nerve roots,
whereas MRI can visualize the entire
brachial plexus, which allows identification of neuromas, inflammation, edema,
and mass lesions within or adjacent to
the brachial plexus. The ability of MRI
myelography to aid in the diagnosis of
root avulsions approaches that of CT
myelography.
13,18,20-23
However, in the
acute setting, CT myelography is the
preferred advanced imaging study of
this chapter’s authors.
markedly improved the ability to identify
a nerve root avulsion. With avulsion, the
dural sac can rupture and subsequently
heal, producing a pseudomeningocele,
which is characteristic of a preganglionic
Electrodiagnostic Studies
Electrodiagnostic studies, such as electromyography (EMG) and nerve conduction velocity studies, are extremely
useful in evaluating the extent of recovery and in preoperative and intraoperative decision making. For closed
and certain open BPIs (such as gunshot
wounds) that are not indicated for immediate exploration and nerve repair,
baseline electrodiagnostic studies
should be performed at 3 to 4 weeks
after injury. Otherwise, wallerian degeneration has not fully occurred and
pathologic findings may not be detected.
In addition to a thorough history, physical examination, and imaging studies,
electrodiagnostic studies should be included to assist in the diagnosis and
localization of a BPI.
EMG assesses the resting and functional status of the muscles. Reduced
recruitment of motor unit potentials
and denervation changes (fibrillation
potentials) can be detected in proximal
muscles within a few weeks after a BPI.
In addition, EMG can help evaluate
muscles that are innervated by root level
motor branches (cervical paraspinals,
rhomboids, serratus anterior); dysfunction in these muscles suggests root avulsions. EMG recovery does not always
translate to clinical recovery because
EMG merely indicates that an unknown
number of nerve fibers have reached the
motor end plates. Conversely, EMG will
not detect reinnervation in distal muscles despite ongoing nerve regeneration.
Nerve conduction velocity studies
can help identify the level of injury (preganglionic versus postganglionic) and
the integrity of the tested nerves. Sensory nerve action potentials are present
in preganglionic BPIs because the lesion
is proximal to the DRG and the sensory
nerve cell body remains intact. Therefore, a patient who is insensate in the
associated sensory nerve distribution
when a sensory nerve action potential is
present most likely has sustained a root
avulsion. In contrast, if a sensory nerve
action potential is absent, a postganglionic BPI could have been sustained in
isolation or in combination with a preganglionic injury.
Atlas of Amputations and Limb Deciencies, Fourth Edition © 2016 American Academy of Orthopaedic Surgeons
394
Chapter 32: Brachial Plexus Injuries
Intraoperative use of electrodiagnostic studies is integral to surgical
decision making. Commonly used techniques include nerve action potentials,
somatosensory-evoked potentials, and
motor-evoked potentials. The presence
of a nerve action potential across a nerve
lesion indicates intact (preserved or regenerating) axons and suggests that
nerve recovery will occur with neurolysis alone in 90% of patients.24 The
presence of a somatosensory-evoked
potential or a motor-evoked potential
indicates an intact connection between
the central and peripheral nervous system through a preserved dorsal or ventral rootlet, respectively. Therefore, both
somatosensory-evoked potentials and
motor-evoked potentials are absent in
postganglionic BPIs and in combined
preganglionic and postganglionic BPIs.
Fundamentals of Surgical
Management for BPI
The tenets of brachial plexus reconstruction revolve around patient selection, timing of surgery, and the priority
of restoring function within the upper
limbs.10 Patients are indicated for surgery in the absence of clinical or electrodiagnostic evidence of recovery on
serial examinations or when recovery
is impossible (root avulsions).
The timing of surgery depends largely
on the mechanism of injury. In penetrating injuries with sharp transection of
the brachial plexus, immediate exploration and primary repair is warranted to
facilitate direct nerve coaptation before
the onset of perineural scarring. Penetrating injuries from a blunt object can
be treated in a subacute manner (3 to
4 weeks) to facilitate further demarcation of the neural zone of injury that can
be adequately identified and resected at
the time of surgery. Gunshot wounds are
treated based on the projectile velocity;
BPIs resulting from low-velocity gunshot
wounds often cause neurapraxia, and
spontaneous recovery can be ex pected.
However, in cases of high-velocity
gunshot wounds, surgical exploration
is often necessary because of the magnitude of associated soft-tissue damage.
10
For closed BPIs, the timing of surgery
depends largely on the type of nerve injury. For root avulsions, early surgery
is recommended at 3 to 6 weeks after
injury, whereas presumed ruptures and
stretch injuries should be explored at 3
to 6 months after serial examinations
with demonstration of inadequate or absent reinnervation. Typically, brachial
plexus exploration and reconstruction
should be performed by 6 months after
injury.11 Poor outcomes can be expected
in patients who undergo brachial plexus
reconstruction beyond 6 to 9 months
after injury because motor end plates degenerate before the regenerating nerves
can reach the target muscles.10 After 1
year, brachial plexus reconstruction
is not advised because of progressive
neural death and irreversible muscle
atrophy.
11
The priority of brachial plexus reconstruction is to restore elbow function, obtain shoulder abduction and
stability, regain hand sensibility, provide wrist flexion and finger extension,
and establish hand intrinsic function.10
These functions can be obtained with
primary and secondary brachial plexus
reconstruction. Primary brachial plexus
reconstruction refers to the initial surgical management to include neurolysis, direct nerve repair, nerve grafting,
nerve transfers, and FFMTs. Secondary
brachial plexus reconstruction is performed to improve the gains achieved
with primary reconstruction or if prior
attempts at reconstruction have failed;
examples include tendon/muscle trans
fers, FFMTs, arthrodesis, and corrective
osteotomies.
10,25
Primary Brachial Plexus
Reconstruction
Direct Nerve Repair
Although not commonly performed
to treat stretch BPIs, direct nerve repair with epineural sutures can be
performed for the acute management
of sharp penetrating trauma such as
lacerations and transections. Nerve retraction and scarring seldom can result
in a tension-free direct repair when performed subacutely.
11
Neurolysis
Neurolysis is integral to brachial plexus
exploration and in preparation for nerve
grafting or transfers. Neurolysis alone is
performed only when nerve continuity
is noted, if a nerve action potential can
be conducted across the lesion, and if
somatosensory-evoked potentials can
be observed.
23
Nerve Grafting
Interposition nerve grafting can be performed in the presence of a postganglionic rupture or absent nerve action
potentials across a lesion within an
intact nerve. Before nerve grafting is
performed, it is imperative to excise all
injured portions of the nerve, the entire
neuroma, and the distal and proximal
stumps until healthy-appearing nerve
fascicles are encountered. Because the
external appearance and consistency of
a damaged nerve does not often correlate
with the internal appearance and potential for nerve recovery, histopathologic
examination and acetylcholinesterase
staining have been advocated to evaluate
the nerve fascicles.
26,27
Typically, wh en
viable nerve roots are available for intraplexal nerve grafting, each spinal level
is used for a specific function: C5 for
shoulder abduction (axillary and suprascapular nerve), C6 for elbow flexion
(musculocutaneous), and C7 for elbow
and wrist extension (radial nerve).
10,28
Various autogenous donor nerve
grafts are available for nerve grafting.
This chapter’s authors prefer to harvest
the sural nerves, which are reversed and
placed in parallel fashion to match the
recipient nerve diameter and fascicular
cross-sectional area (cable nerve graft).
Ipsilateral cutaneous nerves also can
be harvested, including the superficial
© 2016 American Academy of Orthopaedic Surgeons Atlas of Amputations and Limb Deciencies, Fourth Edition
395
Section 2: Upper Limb
Figure 8
motor branch. (Courtesy of the Mayo Foundation for Medical Education
and Research, Rochester, MN.)
branch of the radial, medial brachial
cutaneous, and medial and/or lateral
antebrachial cutaneous nerves. In documented cases of C8 and T1 avulsions,
the ipsilateral vascularized ulnar nerve
graft (based on the superior ulnar collateral artery) can be used with the
theorized benefit of accelerated axonal
regeneration.
Illustration shows intercostal ner ve transfers to the biceps
reconstruction include the ipsilateral intercostal and spinal accessory nerves.
With approximately 1,200 to 1,300
axons per intercostal nerve, up to four
intercostal motor nerves (the third
through the sixth) can be transferred
to the biceps motor branch or can power an FFMT to restore elbow flexion
11
(Figure 8). The intercostal sensory
nerves can be selectively transferred to
Nerve Transfers
Nerve transfers (neurotization) can be
performed for all BPIs. The postulated
benefit of nerve transfers for postganglionic BPIs is to decrease the distance
required for nerve regeneration by transferring a viable motor nerve as close to
the motor end plate as possible, which
can accelerate motor recovery in a more
reliable manner compared with nerve
grafting.11 Donor nerves for transfer can
be obtained from outside (extraplexal)
or within (intraplexal) the brachial
plexus.
The most common extra plexal do-
nor nerves used in brachial plexus
restore upper limb sensibility. The intercostal nerves should be used cautiously
in the setting of multiple rib fractures.
The distal trunk of the spinal accessory
nerve has approximately 1,500 to 1,700
myelinated fibers (predominately motor
fibers) that can be directly transferred
to the suprascapular nerve or with an
interposition nerve graft to the biceps
motor branch (Figure 9). After these
nerve transfers, patients report minimal
chest wall discomfort and note minimal
loss of trapezius function, respectively.
Extraplexal nerve transfers have
expanded to include the phrenic and
the contralateral C7 nerves.
Figure 9
motor branch. (Courtesy of the Mayo Foundation for Medical Education
and Research, Rochester, MN.)
Illustration of spinal accessor y nerve transfer to the biceps
approximately 800 myelinated fibers
29,30
within the phrenic nerve, its course
through the typical supraclavicular approach facilitates convenient transfer to
the suprascapular nerve or directly to
its divisions.10 Interposition nerve grafts
can extend the phrenic nerve transfer
10,11
to reach the musculocutaneous or axillary nerves. Ipsilateral phrenic nerve
harvest can result in a 10% decrease in
pulmonary vital capacity that returns
to baseline between 6 and 24 months;
therefore, this nerve should not be transferred in patients with severe chest trauma or in children younger than 2 years.11
The C7 nerve root has approximately
27,000 to 30,000 nerve fibers and has
been used to restore shoulder, elbow,
and grasp function.
10,11,33,34
Intraplexal nerve transfers use expendable fascicles or branches from viable nerves within the brachial plexus
to power target muscles. Some examples of intraplexal donor and recipient nerves include the thoracodorsal,
31,3 2
With
medial pectoral, and median nerve
Atlas of Amputations and Limb Deciencies, Fourth Edition © 2016 American Academy of Orthopaedic Surgeons
396
Chapter 32: Brachial Plexus Injuries
Images demonstrate the Oberlin technique of nerve transfer of the ulnar nerve
included); these transfers also have restored M4 biceps and deltoid strength
with no noticeable loss of hand function
11,42,43
40-44
(Figures 11 and
or elbow extension strength.
Free-Functioning Muscle Transfer
FFMT using intraplexal or extra plexal
donor nerves can be performed to
fascicles transferred to the biceps motor branch and the distal anterior interosseous nerve transferred to the deep
motor branch of the ulnar nerve.
11,35-3 9
Two common intraplexal nerve transfers include flexor carpi ulnaris motor
branch fascicles of the ulnar nerve to the
biceps motor branch for elbow flexion
Figure 10
(UN) fascicle to the biceps motor (BM) branch. A, The surgical site and the incision. B, The BM
branch is mobilized and transected (dashed line) from the musculocutaneous nerve. C, The UN
motor fascicle to the exor carpi ulnaris is identied, mobilized, and transected (dashed line).
D, The UN motor fascicle is coapted to the BM branch using microsurgical techniques. E, Intraoperative photograph showing the BM branch and the UN. (Courtesy of the Mayo Foundation for
Medical Education and Research, Rochester, MN.)
(Oberlin nerve transfer) (Figure 10)
and the motor branch of the long head
of the triceps to the axillary nerve for
shoulder abduction (Leechavengvongs
nerve transfer)
12). The Oberlin and Leechavengvongs
nerve transfers are indicated for C5 and
C6 avulsion (in some instances C7 is
© 2016 American Academy of Orthopaedic Surgeons Atlas of Amputations and Limb Deciencies, Fourth Edition
397
Section 2: Upper Limb
Figure 11
overlying skin incision (dashed line). B, Planned nerve transfer. C, Completed nerve transfer. (Courtesy of the Mayo Foundation for Medical Education
and Research, Rochester, MN.)
Illustrations demonstrate the Leechavengvongs nerve transfer of the triceps motor branch to the axillary nerve. A, Overview and
better elbow flexion was noted in 80%
and 63% of patients who underwent
FFMT to restore single or dual function,
respectively.
Secondary Brachial
Plexus Reconstruction
of the Shoulder
Glenohumeral motor function has been
categorized into three groups: the prime
movers, the steering group, and the depressor group.45 The prime movers (the
deltoid and the clavicular head of the
pectoralis major) provide lifting power, the steering group (the subscapularis, supraspinatus, and infraspinatus)
guides humeral motion and provides additional lifting power, and the depressor
Figure 12
nerve transfer of the triceps motor branch (T) from the radial nerve (RN) to the axillary nerve (AN).
Note the cutan eous branch (CB) of the axillar y nerve. (Courtesy of the M ayo Foundation for Medical
Education and Research, Rochester, MN.)
restore vital function within the limb
with a BPI. Single- or double-gracilis FF
MTs have been reported to obtain elbow
flexion alone or in addition to finger extension and finger and thumb flexion,
respectively.6 The authors of this chapter
transfer the contralateral gracilis to the
upper limb using the thoracoacromial
Clinical photographs obtained before (A) and after (B) the Leechavengvongs
artery as a donor artery, the cephalic
-
vein as the venous outflow, and the
spinal accessory or multiple intercostal
nerves as the source of nerve reinnervation to provide elbow flexion alone
(Figure 13, A), elbow flexion and wrist
extension (Figure 13, B), or elbow and
finger flexion11 (Figure 13, C). M4 or
group (the sternal head of the pectoralis
major, latissimus dorsi, teres major, and
teres minor) rotates the humeral shaft
and helps achieve full overhead humeral elevation.25 All groups must work in
concert for synchronized motion of the
upper limbs. With a BPI, paralysis of any
of these muscles can result in an imbalance and cause painful subluxation of
the glenohumeral joint.
In addition to restoring shoulder
motion, correcting shoulder instability and imbalance is critical for overall
Atlas of Amputations and Limb Deciencies, Fourth Edition © 2016 American Academy of Orthopaedic Surgeons
398
Chapter 32: Brachial Plexus Injuries
Figure 13
exion (C). (Courtesy of the Mayo Foundation for Medical Education and Research, Rochester, MN.)
upper limb function and for pain control. Shoulder stabilization can improve outcomes after brachial plexus
reconstruction, specifically FFMT for
elbow flexion and prehension.46 The
goals of shoulder reconstruction in the
Illustrations of free-functioning muscle transfers for elbow exion (A), elbow exion and wrist extension (B), or elbow and nger
in external rotation have been noted in
early postoperative follow-up, recurrent deformity can occur.47 Release of
the pectoralis major, in addition to concomitant tendon transfer, also has been
advocated.
50,51
setting of a BPI are pain relief (from
shoulder subluxation), stability, and
restoration of forward elevation, abduction, and external rotation.25 These
goals can be obtained with soft-tissue
releases, tendon transfers, derotational
osteotomy of the humerus, or shoulder
arthrodesis.
Shoulder Tendon Transfers
Shoulder abduction and forward flexion can be restored with various tendon
transfers. Classically, the upper trapezius muscle transfer has been used to
improve shoulder stability.
52-54
The initial technique entailed transfer of the
bony acromial insertion of the upper
Shoulder Soft-Tissue Release
With any tendon transfers about the
shoulder, it is imperative that the joint is
supple, with full passive range of motion
to optimize secondary reconstruction
outcomes. Preganglionic C5 and C6 lesions can result in unopposed shoulder
internal rotation attributable to the subscapularis (C7) and teres major (C7), in
addition to adduction afforded by the
pectoralis major (C8 and T1). Internal
rotation contracture can be corrected by
releasing the origin of the subscapularis
from the medial border of the scapu-
47-4 9
la.
Although marked improvements
trapezius to the humeral shaft (distal to
the greater tuberosity).
45,55
A later modification involved medial advancement of
the deltoid over the transferred trapezius
to improve shoulder stability.56 Approximately 95% of the patients (70 of 74)
who underwent trapezius transfer in
one series were satisfied with shoulder
stability and function.53 Mean shoulder
abduction after trapezius transfer ranged
from 39° to 116°.
53,54,57-60
Other tendon
transfers about the shoulder have been
described, including transfer of the latissimus dorsi (with or without the teres
major) and pectoralis major.
61-65
Based on anatomic feasibility studies,
the authors of this chapter have expanded the role of tendon transfers in the
paralytic shoulder. Isolated transfer of
the lower trapezius to the infraspinatus can be performed directly to restore
active shoulder external rotation if the
glenohumeral joint remains reduced
with adequate passive range of motion
and minimal degenerative change66
(Figure 14). In complete BPIs, complex
shoulder reconstruction can be performed with transfers of the upper and
middle trapezius to the deltoid, the levator scapulae to the supraspinatus, the
lower trapezius to the infraspinatus, and
the upper serratus to the subscapularis,
provided that all donor muscles exhibit
a minimal M4 level strength.
45,67-69
Derotational Humeral Osteotomy
Derotational osteotomy of the humerus corrects hand and forearm malpositioning, which can improve upper
limb function. The procedure can be
performed as an alternative to shoulder
tendon transfers to enable external rotation or as a salvage procedure if primary brachial plexus reconstruction
or tendon transfers (latissimus dorsi or
© 2016 American Academy of Orthopaedic Surgeons Atlas of Amputations and Limb Deciencies, Fourth Edition
399
Section 2: Upper Limb
teres major) fail.
70-73
If a glenohumeral
internal rotation contracture exists even
with restoration of elbow flexion, the
patient’s forearm can limit elbow flexion
by striking the chest.53 The osteotomy
is performed just proximal to the deltoid insertion, and approximately 30°
of external rotation is introduced to the
distal segment.70 In one series, humeral
derotational osteotomy yielded a mean
correction of external rotation to 27°.
60
Shoulder Arthrodesis
The goal of glenohumeral arthrodesis
is to provide a stable foundation within the upper limb kinetic chain, focusing all brachial plexus reconstruction
efforts on restoring elbow and hand
function. A flail shoulder can result in
painful inferior glenohumeral subluxation and inability to position the hand
in space. If the trapezius and levator
scapulae remain intact after BPI, useful
scapulothoracic motion can be achieved
after glenohumeral arthrodesis.74 Preserved serratus anterior function can
even allow forward flexion of the upper
limb through scapular rotation while
persistent pectoralis major function
permits brachiothoracic grasp.
74,75
Many factors affect outcomes after
glenohumeral arthrodesis, including
position of the fusion, particularly in
internal rotation; continued pain; and
residual hand function.
74,76 -79
However, glenohumeral arthrodesis has been
shown to improve function in patients
with complete BPIs, with restored elbow
flexion despite poor hand function.
75
Recent advances in nerve grafting and
transfer has limited the role of primary
glenohumeral arthrodesis because patients prefer voluntary shoulder abduction if it can be achieved.
10,46
Functional
outcomes of brachial plexus reconstruction to restore shoulder function are less
predictable than for restoration of elbow
function; thus, glenohumeral arthrodesis can be considered a salvage proce-
75,80 -83
dure.
Rouholamin et al74 reported
on 13 patients with BPIs (4 complete, 7
Figure 14
A, Normal position of the lower trapezius. B, Elevation of the lower trapezius to the uninjured
spinal accessory nerve. C, Transfer to the infraspinatus tendon. (Courtesy of the Mayo Foundation
for Medical Education and Research, Rochester, MN.)
upper trunk, and 2 lower trunk) who
underwent glenohumeral arthrodesis in
30° of abduction, 30° of flexion, and 20°
of internal rotation, with mean postoperative active abduction of 56° (range,
50° to 80°). Ten patients had excellent
pain relief from preoperative levels and
12 perceived an improvement in postoperative limb function. For complete
and partial BPIs, Atlan et al84 observed
respective mean active abduction of 57°
Images demonstrate ipsilateral lower trapezius transfer to the infraspinatus.
and 62° and respective mean active arc
of rotation of 50° and 46°. Chammas
et al75 noted improved hand excursion
and strength of shoulder adduction and
external rotation if the inferior head of
the pectoralis major had at least M3
strength, and improved active shoulder
range of motion and strength of adduction and internal rotation if the superior
head of the pectoralis major had at least
M3 strength.
Atlas of Amputations and Limb Deciencies, Fourth Edition © 2016 American Academy of Orthopaedic Surgeons
400
Chapter 32: Brachial Plexus Injuries
Secondary Brachial
Plexus Reconstruction
of the Hand and Wrist
Wrist, umb Interphalangeal, and
Trapeziometacarpal Arthrodesis
In addition to positioning the terminal limb in space, functional hand
movement requires the ability to
grasp and release.
don transfers and FFMTs can restore
hand function, many factors can impede outcomes. A basic tenet of tendon
transfer is to provide a straight line of
pull, which is difficult to achieve for
finger and thumb flexors in patients
with BPIs because of wrist instability
and thumb malposition with instabilit y.87 With wrist instability, tendon
excursion and strength are wasted on
useless wrist motion instead of vital
finger and thumb motion as the tendon
transfer or FFMT courses across a flaccid wrist. With the loss of thumb intrinsic and/or extrinsic motor tone that
helps position the thumb for pinch, the
imbalance of forces results in a supinated thumb with trapeziometacarpal
hyperextension and interphalangeal
joint hyperflexion that neutralizes any
attempts to restore pinch.
Combined wrist, thumb interphalangeal joint, and trapeziometacarpal
arthrodesis can improve hand function
after brachial plexus reconstruction.
Wrist arthrodesis results in a stable,
painless carpus that enhances aesthetics
and improves hygiene.
more, it can augment reconstruction
efforts to reanimate the hand. Addosooki et al89 performed wrist arthrodesis, in addition to double free-muscle
transfers to restore hand prehension,
and observed improved finger range of
motion and overall hand function.
Similarly, the addition of thumb interphalangeal joint and trapeziometacarpal
arthrodesis can improve thumb pinch
after FFMT performed for BPI.6 In one
series, concomitant wrist, thumb interphalangeal joint, and trapeziometacarpal arthrodesis were performed as
10,85,86
Although ten-
53,87-90
Further-
89,91
secondary procedures in 24 patients,
resulting in substantial improvements
in mean Disabilities of the Arm, Shoulder and Hand scores (from 51 preoperative to 28 postoperative; P < 0.001)
and pain scores (from 5.3 preoperative
to 3.2 postoperative; P < 0.001) with
overall improvements in appearance,
function, daily care, hygiene, pain, and
satisfaction.
87
The Role of
Amputation in BPIs
Isolated Transradial Amputation
Transradial amputation can be performed and a terminal prosthesis fitted
to improve upper limb function in cases
of lower trunk BPIs or when reconstruction fails to reanimate the hand, provided that elbow and shoulder function
have been restored or are maintained.
Proponents of transradial amputation
postulate that preserved elbow proprioception improves the usefulness and
degree of acceptance of the prosthesis.92
Even in the setting of a flail elbow and
insensate residual limb, proprioception
may be intact and successful prosthetic
fitting can be achieved without wound
problems.
However, elective transradial amputation is rarely performed because
of recent advances in distal nerve
transfers, such as the anterior interosseous nerve transfer to the deep motor branch of the ulnar nerve, and the
ability to enhance prehension with tendon transfers and FFMTs with selective wrist and hand arthrodesis.
Allieu and Cenac1 recommended that
“no patient should be subjected to
forearm amputation…if they have active elbow flexion. It is always better
for the patient to have a soft pliable
hand for human contact, even if it is
insensate and paralyzed, rather than
a cold inanimate orthosis.” The only
indication for isolated transradial amputation is recurrent complications
such as infection and injury resulting
from an insensate hand that has no
38, 39,87
evidence of nerve recovery even after
reconstruction.
Isolated Transhumeral Amputation
Isolated transhumeral amputation to
treat complete BPIs has been largely
abandoned; however, it can be performed in select patients. With advances
in microsurgery, patients without evidence of neurologic recovery initially
should undergo brachial plexus exploration and reconstruction. In 1980,
Rorabeck93 reported on 14 patients with
a complete BPI who underwent primary transhumeral amputation within 6
weeks to 3 years of injury with the primary indication to accelerate rehabilitation or for pain relief. After amputation,
eight patients wore their prosthesis for
more than 8 hours per day and only one
patient used the prosthesis for functional purposes. Of six patients who underwent amputation for pain relief, three
noted pain relief postoperatively. Neuropathic pain associated with BPI is centrally mediated; therefore, amputation
will not provide pain relief and should
never be performed for this reason.
Historically, the indications for transhumeral amputation were for repeated
infections and/or injury to an insensate
limb or when the flaccid arm interferes
with the patient’s activities and is requested.94 The current indications for
elective amputation are no evidence of
recovery in the setting of a complete,
preganglionic BPI with chronic complications, such as recurrent injury or
infection; a well-informed patient who
is willing to undergo multidisciplinary
care, such as consultations with rehabilitation staff, psychologists, and prosthetic team members; a patient who
understands that centrally mediated
neuropathic pain will not improve, although shoulder pain from inferior subluxation caused by the weight of the arm
may improve; and a patient who agrees
that the goal of amputation is to improve
activities of daily living and to prevent
injury to an insensate limb.
© 2016 American Academy of Orthopaedic Surgeons Atlas of Amputations and Limb Deciencies, Fourth Edition
401
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