The patient is positioned supine with the arm placed on a radiolucent hand
table. Fluoroscopy is used intraoperatively to confirm reduction of the
fracture. A well-padded sterile pneumatic tourniquet is applied. Following
general or regional anesthesia, the injured elbow is assessed clinically for
ligamentous stability.
Open reduction of capitellartrochlear fractures
(Figs. 2-A and 2-B) is
performed with use of an extensile lateral
exposure2,4,7,9,11,15,16.
A lateral skin incision (Fig.
3) at the elbow is centered over the lateral epicondyle and
extends from the anterior aspect of the lateral column of the distal end of
the humerus to approximately 2 cm distal to the radial head
(Fig. 4-A).
Following dissection through the subcutaneous tissue layers, the lateral
column is palpated (Fig. 4-B).
With the forearm pronated to move the radial nerve away from the surgical
field, the common origin of the radial wrist extensors in conjunction with the
anterior capsule is elevated sharply as a full-thickness sleeve from the
lateral supracondylar ridge anteriorly. Distally, the Kocher interval is
identified and connected to the proximal exposure to develop a continuous
full-thickness anterior soft-tissue flap
(Fig. 4-C). With the elbow
flexed, intracapsular retractors are placed deep to the brachialis and the
anterior capsule and over the medial column facilitating exposure of the
anterior distal humeral articular fracture fragments and the radial head
(Fig. 4-D). The fracture site
is débrided of hematoma and soft-tissue debris to allow visualization
of the fracture fragments. Retractors are not placed anterior to the radial
neck to reduce the risk of an iatrogenic injury to the posterior interosseous
nerve.
When posterior metaphyseal comminution is present, the lateral aspect of
the triceps may also be elevated from the lateral column and the proximal
ulnar metaphysis. Care is taken to preserve the lateral ulnar collateral
ligament origin at the lateral epicondyle
(Fig. 4-C) and the vascular
supply to the capitellum. Release of the lateral ulnar collateral
ligament2,3,11,17
is not always necessary even when there is trochlear extension of the coronal
shear capitellar fracture. In patients with a lateral epicondylar fracture
fragment (i.e., a Bryan and Morrey Type-III
fracture1; or a Ring
Type-II, III, or IV
fracture3), the
epicondylar fragment with the lateral collateral ligamentous complex origin
can be reflected distally to enhance
exposure3,11,17.
Utilizing the lateral extensile exposure does not seem to increase the risk of
osteonecrosis of the capitellum or
trochlea2,3,11,16,17.
Anatomic reduction is directly visualized; as the articular segment is
reduced along the proximal metaphyseal margin and trochlea, the capitellar
fracture is provisionally fixed with a minimum of two 0.045 or 0.062- in (1.14
or 1.57-mm) Kirschner wires (Fig.
5-A). Anatomic reduction is then confirmed with orthogonal
fluoroscopy. When there is sufficient subchondral bone on the articular
segment, buried headless cannulated screws are inserted over the guidewires in
an anterior-to-posterior direction (Figs.
5-B,
5-C, 5-D,
5-E). The terminally threaded
Herbert screw (Zimmer, Warsaw, Indiana) and fully threaded mini-Acutrak
headless screw (Acumed, Hillsboro, Oregon) provide fracture site compression
through variable thread pitch designs. A minimum of two screws are used in
larger fragments to ensure rotational control
(Figs. 6-A and 6-B). Care is
taken to spread the screws sufficiently to avoid iatrogenic fracture of the
capitellum. The radial wrist extensors are repaired to the soft-tissue cuff on
the lateral supracondylar ridge, and the Kocher interval is closed in
continuity with the proximal exposure of the lateral column
(Fig. 7). The remainder of the
wound closure proceeds in a standard, layered fashion.
Supplemental fixation may be required to reconstruct more complex fracture
patterns with posteroinferior-lateral metaphyseal comminution and/or trochlear
extension (i.e., Type-III and IV fractures). Supplemental fixation options
include minifragment screws, threaded Kirschner wires, and bioabsorbable pins
for small (i.e., <5-mm) osteochondral capitellar-trochlear fragments. When
there is extensive involvement of the lateral column or substantial
posterolateral comminution, supplemental plate fixation with pelvic
reconstruction, precontoured, or locking (i.e., fixed-angle) plates may be
required to buttress the lateral
column3,4,17.
When there is a concomitant radial head fracture, it is addressed through the
same exposure (Fig. 8). When a
lateral ulnar collateral ligament avulsion is identified or the lateral
epicondyle fragment is too small to accept screw fixation, the lateral ulnar
collateral ligament is repaired primarily to its origin with use of suture
anchors or transosseous sutures passed through drill-holes, or the fragment is
secured with a figure-of-eight tension-band wire.
When rigid fixation has been achieved, a long arm posterior plaster splint
and compressive dressing is applied with the elbow at approximately 90° of
flexion. At the first office visit (i.e., seven to ten days postoperatively),
the sutures are removed and active and active-assisted range of motion of the
elbow and forearm is initiated. Delayed or protected mobilization with a
hinged functional elbow brace may be necessary when there is concern about the
stability of fixation. A hinged brace with gradual reduction of the extension
block facilitates maintenance of radial head congruity with the reduced
capitellum. Static progressive extension thermoplastic splinting is used when
a flexion contracture occurs in the early postoperative period. Strengthening
exercises are initiated when there is clinical and radiographic evidence of
fracture union.
CRITICAL CONCEPTSINDICATIONS:Isolated displaced, capitellar-trochlear coronal-plane shear fractures of
the distal humeral articular surface. These are relatively rare injuries.Capitellar-trochlear shear fractures occurring in association with complex
distal humeral fractures and elbow fracture-dislocations with concomitant
ligamentous injuries.CONTRAINDICATIONS:There are no absolute contraindications to performing open reduction and
internal fixation of capitellar fractures. If stable reconstruction of the
articular surface cannot be achieved, total elbow arthroplasty may be
considered in some elderly or osteoporotic patients. Total elbow arthroplasty
represents a salvage option for severe symptomatic posttraumatic arthritis,
articular osteonecrosis, nonunion or malunion, and elbow instability. Closed
treatment with immobilization or fragment excision is only indicated in very
select cases (i.e., a Type-II fracture).PITFALLS:Underestimation of fracture complexity. The exact morphology of the
fracture is often difficult to ascertain from preoperative plain radiographs
alone. Computed tomographic images help to define the medial extent of the
fracture, articular impaction, and metaphyseal and condylar comminution.
Imaging must be carefully assessed for the presence of the "double
arc" sign, representing medial trochlear extension, metaphyseal
comminution, and radial head and/or neck pathology. Concomitant lateral and/or
medial collateral ligament disruptions or their osseous functional equivalents
must be recognized and repaired in order to restore elbow stability.Inadequate exposure of the radiocapitellar compartment and visualization of
the trochlea and medial articular extension. Extensile surgical exposures and
a variety of implants are required to address the more complex fracture
patterns, which are characterized by metaphyseal comminution and ipsilateral
radial head fracture, and often require supplemental fixation. On the basis of
the fracture pattern, the surgeon should be prepared to perform a supplemental
medial-based exposure—flexor-pronator split or elevation—when the
medial aspect of the trochlea cannot be visualized from a lateral approach or
when there is involvement of the medial column. A single posterior midline
skin incision followed by elevation of full-thickness medial and lateral skin
flaps and an olecranon osteotomy is indicated when trochlear comminution or
extension of the articular fracture beyond the radiocapitellar compartment
(i.e., a Ring Type-V
fracture3 with
medial epicondylar extension) is identified preoperatively.Failure to restore articular congruity.Potential for ulnohumeral instability if the trochlea-olecranon
articulation is not restored.Failure to recognize posteroinferior metaphyseal comminution, which may
require a cancellous allograft.Iatrogenic injuries to the posterior interosseous nerve.Iatrogenic injury to the lateral ulnar collateral ligament.Prolonged postoperative immobilization.AUTHOR UPDATE:There have been no changes in the surgical technique since publication of
the original article.
CRITICAL CONCEPTS
INDICATIONS:
Isolated displaced, capitellar-trochlear coronal-plane shear fractures of
the distal humeral articular surface. These are relatively rare injuries.Capitellar-trochlear shear fractures occurring in association with complex
distal humeral fractures and elbow fracture-dislocations with concomitant
ligamentous injuries.
Isolated displaced, capitellar-trochlear coronal-plane shear fractures of
the distal humeral articular surface. These are relatively rare injuries.
Capitellar-trochlear shear fractures occurring in association with complex
distal humeral fractures and elbow fracture-dislocations with concomitant
ligamentous injuries.
CONTRAINDICATIONS:
There are no absolute contraindications to performing open reduction and
internal fixation of capitellar fractures. If stable reconstruction of the
articular surface cannot be achieved, total elbow arthroplasty may be
considered in some elderly or osteoporotic patients. Total elbow arthroplasty
represents a salvage option for severe symptomatic posttraumatic arthritis,
articular osteonecrosis, nonunion or malunion, and elbow instability. Closed
treatment with immobilization or fragment excision is only indicated in very
select cases (i.e., a Type-II fracture).
There are no absolute contraindications to performing open reduction and
internal fixation of capitellar fractures. If stable reconstruction of the
articular surface cannot be achieved, total elbow arthroplasty may be
considered in some elderly or osteoporotic patients. Total elbow arthroplasty
represents a salvage option for severe symptomatic posttraumatic arthritis,
articular osteonecrosis, nonunion or malunion, and elbow instability. Closed
treatment with immobilization or fragment excision is only indicated in very
select cases (i.e., a Type-II fracture).
PITFALLS:
Underestimation of fracture complexity. The exact morphology of the
fracture is often difficult to ascertain from preoperative plain radiographs
alone. Computed tomographic images help to define the medial extent of the
fracture, articular impaction, and metaphyseal and condylar comminution.
Imaging must be carefully assessed for the presence of the "double
arc" sign, representing medial trochlear extension, metaphyseal
comminution, and radial head and/or neck pathology. Concomitant lateral and/or
medial collateral ligament disruptions or their osseous functional equivalents
must be recognized and repaired in order to restore elbow stability.Inadequate exposure of the radiocapitellar compartment and visualization of
the trochlea and medial articular extension. Extensile surgical exposures and
a variety of implants are required to address the more complex fracture
patterns, which are characterized by metaphyseal comminution and ipsilateral
radial head fracture, and often require supplemental fixation. On the basis of
the fracture pattern, the surgeon should be prepared to perform a supplemental
medial-based exposure—flexor-pronator split or elevation—when the
medial aspect of the trochlea cannot be visualized from a lateral approach or
when there is involvement of the medial column. A single posterior midline
skin incision followed by elevation of full-thickness medial and lateral skin
flaps and an olecranon osteotomy is indicated when trochlear comminution or
extension of the articular fracture beyond the radiocapitellar compartment
(i.e., a Ring Type-V
fracture3 with
medial epicondylar extension) is identified preoperatively.Failure to restore articular congruity.Potential for ulnohumeral instability if the trochlea-olecranon
articulation is not restored.Failure to recognize posteroinferior metaphyseal comminution, which may
require a cancellous allograft.Iatrogenic injuries to the posterior interosseous nerve.Iatrogenic injury to the lateral ulnar collateral ligament.Prolonged postoperative immobilization.
Underestimation of fracture complexity. The exact morphology of the
fracture is often difficult to ascertain from preoperative plain radiographs
alone. Computed tomographic images help to define the medial extent of the
fracture, articular impaction, and metaphyseal and condylar comminution.
Imaging must be carefully assessed for the presence of the "double
arc" sign, representing medial trochlear extension, metaphyseal
comminution, and radial head and/or neck pathology. Concomitant lateral and/or
medial collateral ligament disruptions or their osseous functional equivalents
must be recognized and repaired in order to restore elbow stability.
Inadequate exposure of the radiocapitellar compartment and visualization of
the trochlea and medial articular extension. Extensile surgical exposures and
a variety of implants are required to address the more complex fracture
patterns, which are characterized by metaphyseal comminution and ipsilateral
radial head fracture, and often require supplemental fixation. On the basis of
the fracture pattern, the surgeon should be prepared to perform a supplemental
medial-based exposure—flexor-pronator split or elevation—when the
medial aspect of the trochlea cannot be visualized from a lateral approach or
when there is involvement of the medial column. A single posterior midline
skin incision followed by elevation of full-thickness medial and lateral skin
flaps and an olecranon osteotomy is indicated when trochlear comminution or
extension of the articular fracture beyond the radiocapitellar compartment
(i.e., a Ring Type-V
fracture3 with
medial epicondylar extension) is identified preoperatively.
Failure to restore articular congruity.
Potential for ulnohumeral instability if the trochlea-olecranon
articulation is not restored.
Failure to recognize posteroinferior metaphyseal comminution, which may
require a cancellous allograft.
Iatrogenic injuries to the posterior interosseous nerve.
Iatrogenic injury to the lateral ulnar collateral ligament.
Prolonged postoperative immobilization.
AUTHOR UPDATE:
There have been no changes in the surgical technique since publication of
the original article.