Download Supine Extensile Approach to the Anterolateral Humerus

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Section Editor: Steven F. Harwin, MD
Supine Extensile Approach to the Anterolateral
Humerus
Michael A. Kuhne, MD; Darin Friess, MD
Abstract: The radial nerve is at risk of injury during surgical approaches to the humeral shaft. Previous authors have
described an anterolateral approach to the humerus limited
by the radial nerve, requiring that distal dissection be carried
anterior into a neurovascularly crowded interval. A novel extensile approach is described using a neuromuscular bridge
to protect the radial nerve, thus enabling safe distal extension
of the anterolateral humerus approach. The authors present a
case series of 7 patients who required an extensile humeral
exposure. To date, there have been no complications, including loss of reduction, malunion, nonunion, or nerve palsy.
[Orthopedics. 2016; 39(1):e193-e195.]
T
he knowledge of extensile extremity approaches
is a useful tool in the armamentarium of the orthopedic
surgeon. To date, there are
few descriptions in the literature of extensile approaches
to the entire humerus. This
novel approach to the anterolateral humerus provides
protection of the radial nerve
while allowing exposure of
the entirety of the anterolateral border of the humerus
and for extended plating to
achieve adequate screw pur-
The authors are from the Naval Hospital Camp Lejeune (MAK), Camp
Lejeune, North Carolina; and the Department of Orthopaedics & Rehabilitation (DF), Oregon Health & Science University, Portland, Oregon.
Dr Kuhne has no relevant financial relationships to disclose. Dr Friess is
a paid consultant for Accumed, LLC.
Correspondence should be addressed to: Darin Friess, MD, Department
of Orthopaedics & Rehabilitation, Oregon Health & Science University,
3181 SW Sam Jackson Park Rd, OP-31, Portland, OR 97239 (friessd@ohsu.
edu).
Received: June 10, 2014; Accepted: November 14, 2014.
doi: 10.3928/01477447-20151222-17
chase and plate stability.
Strong distal fixation in a potentially short distal segment
is possible with this technique
due to the large medial-lateral
bony diameter. The technique
described is a combination
of an anterolateral humeral
approach1,2 with bridging to
a lateral elbow (Kocher3) approach distally. If necessary,
the approach may be extended proximally into a deltopectoral approach, which has
been previously described in
the literature.1,2
Iatrogenic injury to the
radial nerve occurs in 5% of
cases of humeral open reduction and internal fixation.2
Campbell’s text describes
an anterolateral humerus approach that must terminate 5
cm proximal to the elbow due
to the presence of the radial
nerve.4
Gerwin et al5 described an
extensile posterior approach
to the humerus and performed
a cadaveric study mapping
the course of the radial nerve.
Based on the results of this
study, the radial nerve crosses
the lateral intermuscular septum at 10.2±0.4 cm proximal to the lateral epicondyle.
With a modified posterior approach, the authors reported
exposure of 94% of the distal
humerus,5 but this approach
requires a lateral or supine
position, which is not always
possible.
In his text on extensile exposures, Henry1 described an
anterolateral approach with
splitting of the brachialis
and coursing anterior on the
elbow to protect the radial
nerve. This limits the exposure of the lateral border of
the distal humerus, thus exposing a more anterior approach than described here,
and also risks denervation in
splitting the brachialis despite
its dual nerve innervation (radial nerve and musculocutaneous nerve).
Mekhail et al6 described
an extensile anterolateral approach requiring exposure of
the radial nerve with the dissection traveling anterior to
the brachioradialis to expose
the distal humerus.
JANUARY/FEBRUARY 2016 | Volume 39 • Number 1e193
n tips & techniques
Figure 1: The proximal (shoulder, left) portion of the anterolateral approach
was carried distally (elbow, right) to the extent of the mobile wad (hemostat
identifies radial nerve).
Figure 2: With the distal Kocher interval opened, a Cobb elevator was slid
subperiosteally under the mobile wad and radial nerve. Left is proximal at the
shoulder and right is distal to the elbow.
The approach described in
the current study allows for
lateral humeral plating and
exposure of the entirety of the
humerus, while protecting the
radial nerve. The authors’ experience using this technique
in 7 patients requiring extensile humeral exposure for
open reduction and internal
fixation is reported.
Materials and Methods
Institutional review board
approval for chart review was
obtained for patients requiring extensile anterolateral
humeral exposure for open
reduction and internal fixation from January 1, 2006, to
December 1, 2010, by a single
surgeon (D.F.) at the authors’
e194
level I tertiary care trauma
center. Chart review was performed in accordance with
ethical standards for experiments on human subjects.
Surgical Technique
Preoperative patient management is a crucial part of
the surgical preparation. The
authors recommend against
using a preoperative nerve
block or skeletal relaxation
for control of intraoperative
pain to allow intraoperative
testing of muscle and nerve
function with electrical stimulation such as electrocautery.
Surgeon and patient discussion of the risks of the operative intervention, including infection, damage to the
radial and musculocutaneous
nerves, fracture nonunion or
malunion, and loss of fixation, is important.
Patients were placed supine with the operative arm
extended on a radiolucent
arm board. Patients were
prepped and draped in sterile
fashion with the entire arm
prepped free for intraoperative manipulation. Adhesive
covering (Ioban; 3M, St Paul,
Minnesota) was used to seal
the proximal portion of the
drapes.
Anatomic landmarks, including the coracoid, deltopectoral groove, lateral
bicipital sulcus, and lateral
epicondyle, were marked. The
incision ran proximally along
the border of the biceps and
the brachialis. It was carried
distally to the lateral epicondyle, extending a few centimeters distal along Kocher’s
interval.
Beginning with the proximal exposure, the deltopectoral groove was identified
(Figure 1). The cephalic vein
was often mobilized laterally
with the deltoid. After incision of the brachial fascia, the
biceps was mobilized laterally, exposing the interval
between the biceps and the
brachialis. Prior to reduction and plating, the anterior
insertion of the deltoid may
need to be released.7 Care was
taken to preserve the lateral
brachial cutaneous nerve superficial to the biceps muscle.
The musculocutaneous nerve
was retracted medially with
the biceps. The brachialis was
split longitudinally due to
its internervous interval and
bluntly dissected to bone.7
The dissection was extended
distally until visualization of
the forearm extensor musculature (mobile wad) coursing obliquely. This marked
the distal safe interval, as the
mobile wad houses the radial
nerve. The radial nerve is located approximately 10 cm
proximal to the lateral epicondyle.5
Bovie electrocautery could
be used toward the distal aspect of the proximal portion
of this approach and muscular
contraction may be observed
near the nerve. However, this
does not take the place of the
surgeon’s knowledge of anatomy and cautious dissection
principles.
At this point, the dissection started distally at the lateral epicondyle. The proximal
portion of the Kocher interval
between the anconeus and
extensor carpi ulnaris was
developed. It was only necessary to develop the proximal
portion because dissection
to the forearm was unnecessary for the approach.3 Once
at the distal humerus, a Cobb
elevator was meticulously slid
along the humerus subperiosteally from proximal to distal
and from distal to proximal,
thus providing 2 windows
with a soft tissue bridge housing the radial nerve, mobile
wad, and part of the brachialis
(Figure 2).
A large fragment 4.5-mm
plate of appropriate length
for the fixation of the intended fracture (typically 10
to 14 holes) was chosen. The
authors typically chose a narrow plate for primary fracture
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fixation and a broad plate for
revision fixation. The plate
was contoured with a slight
pre-bend at the shaft and with
a distal flare to accommodate
the supracondylar region, using a table-top bender. The
plate was then slid underneath the forearm extensor
musculature along the lateral humerus. At least 2 or 3
screw holes of the plate distal
to the neuromuscular bridge
were available for screw
fixation traversing the large
lateral to medial diameter of
the distal humerus. One or 2
holes generally remained underneath the muscular bridge
that were not accessible with
retraction and would have
risked damage to the radial
nerve (Figure 3). Once fixation was complete, the wound
was thoroughly irrigated and
closed in standard fashion per
surgeon preference. The skin
was then closed over a drain.
Results
Seven patients in whom
this technique was used were
identified via chart review.
Four patients were indicated
due to complications from
an initial open reduction and
internal fixation: 3 had fracture nonunion (Figure 4)
and 1 sustained a periprosthetic fracture. Two patients
had nonunion after attempted
treatment in a Sarmientotype brace. One patient had a
long-spiral humeral fracture
indicated for primary open
reduction and internal fixation. Among these 7 patients,
there has been no evidence of
nerve injury to date. Postoperatively, 1 patient developed a
superficial infected hematoma
requiring unplanned return to
the operating room for irrigation and debridement.
Discussion
Using an anterolateral humerus approach combined
with a Kocher elbow approach, an extensile humeral
exposure appeared to be a
safe procedure without evidence of radial nerve injury
in this case series. A muscular bridge protecting the
radial nerve was maintained
during internal fixation. Caution must be used in nonunion cases with prior hardware, as scar tissue may make
delineation of the muscular
planes more difficult, thus
putting the radial nerve at
greater risk. The authors’ results are limited by the small
case series; a larger number
of patients are required to
determine the true incidence
of potential nerve injury with
this approach.
Conclusion
Indications for operative
fixation of the humerus, especially an extensile approach,
are limited. Optimal candidates are those with humeral
shaft nonunions, malunions,
fractures surrounding a prior
humerus implant with a prior
anterolateral approach, and
a long fracture pattern that
would not be amenable to
other forms of treatment and
obese or polytraumatized patients who cannot lie lateral
or prone for an extensile posterior approach. With proper
patient selection, this novel
approach enables safe distal
Figure 3: Completed plate fixation of a right humeral shaft nonunion with 2
windows of the extensile approach, with the shoulder to the left and the elbow
to the right.
A
B
Figure 4: Prior to revision surgery, nonunion occurred after failed open reduction and internal fixation (A). Postoperative radiograph of the same patient
using the extensile approach described (B).
extension of the anterolateral
humerus approach with good
outcome.
References
1. Henry AK. Exposures in the
upper limb. In: Henry AK, ed.
Extensile Exposure. 2nd ed.
Baltimore, MD: Williams and
Wilkins; 1963:25-48.
2. Robinson D, O’Brien P. Humeral shaft fractures: open
reduction internal fixation. In:
Wiss D, ed. Master Techniques
in Orthopaedic Surgery: Fractures. 2nd ed. Philadelphia, PA:
Lippincott Williams & Wilkins;
2006:67-80.
3. Ring D. Radial head fractures:
open reduction internal fixation. In: Wiss D, ed. Master
Techniques in Orthopaedic
Surgery: Fractures. 2nd ed.
Philadelphia, PA: Lippincott
Williams & Wilkins; 2006:121141.
4.Crenshaw A. Surgical techniques and approaches. In: Canale ST, Beaty JH, eds. Campbell’s Operative Orthopaedics.
11th ed. Philadelphia, PA:
Mosby Elsevier; 2008:100103.
5.Gerwin M, Hotchkiss RN,
Weiland AJ. Alternative operative exposures of the posterior
aspect of the humeral diaphysis with reference to the radial
nerve. J Bone Joint Surg Am.
1996; 78(11):1690-1695.
6.Mekhail AO, Checroun AJ,
Ebraheim NA, Jackson WT,
Yeasting RA. Extensile approach to the anterolateral surface of the humerus and the
radial nerve. J Shoulder Elbow
Surg. 1999; 8(2):112-118.
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2008:91-104.
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