Open Reduction and Internal Fixation of Phalangeal Condylar Fractures

Greg Merrell

Barrett Weiss

Arnold-Peter Weiss

DEFINITION

Phalangeal condylar fractures include unicondylar and bicondylar intra-articular fracture of the distal ends of the proximal and middle phalanx.
- Proximal phalangeal condylar fractures are more common and, due to the propensity of stiffness at the proximal interphalangeal (PIP) joint regardless of treatment, require careful attention.
- Condylar fractures of the distal middle phalanx, although still frequently requiring treatment, have some degree of forgiveness regarding range of motion (ROM) issues.
Table 1 demonstrates the variety of condylar fracture patterns typically observed.

ANATOMY

Collateral ligaments, finger position, and direction of force play a role in both fracture pattern and the direction of displacement (FIG 1).
Blood is supplied to the condyles by a branch of the digital artery and vein that travels with the collateral ligaments.
- Care must be taken not to disrupt this blood supply or to strip small fragments of their soft tissue attachments.

Table 1 Condylar Fracture Patterns

Fracture Configuration	Illustration	Characteristics	Fixation
Fracture Configuration	Illustration	Characteristics	Nondisplaced Fracture	Displaced Fracture
Type I: unicondylar short oblique		Unstable	Could consider nonoperative treatment but must follow closely. Otherwise, two percutaneous K-wires	Joystick closed reduction and K-wires, open reduction and screws, or K-wires
Type II: unicondylar long oblique		Unstable but fixation is a little easier than type I	Could consider nonoperative treatment but must follow closely. Otherwise, two or three percutaneous K-wires	Joystick closed reduction and K-wires, open reduction and screws, or K-wires
Type III: dorsal coronal		Often stable	<25% and stable joint: consider nonoperative treatment or excision. >25% and nondisplaced: could consider nonoperative treatment but must follow closely. Otherwise, two percutaneous K-wires	>25% and displaced or <25% with subluxed joint: joystick closed reduction and K-wires or open reduction and K-wires (rarely screws)
Type IV: volar coronal		Unstable	<25% and stable joint: consider nonoperative treatment or excision. >25% and nondisplaced: could consider nonoperative treatment but must follow closely. Otherwise, two percutaneous K-wires	>25% and displaced or <25% with subluxed joint: joystick closed reduction and K-wires or open reduction and K-wires (rarely screws)
Type V: bicondylar		Unstable	A nondisplaced fracture: could consider K-wires	Usually requires open reduction and screws, plates, or K-wires
Type VI: triplane-type bicondylar		Unstable	Percutaneous K-wires	Usually requires open reduction with dorsal to volar screws

FIG 1 • Direction of applied force determines the fracture type.

PATHOGENESIS

These fractures often are sports-related injuries.
The mechanism is hypothesized to be tension or rotation force through the collateral ligaments for an oblique fracture and compression and subluxation in the case of a coronal fracture.¹,⁶
Fractures often are unstable because there is a minimal periosteal sleeve, forces seen at the joint are substantial, and the oblique nature of the fracture line is inherently unstable.
Most commonly, the condyle toward the midline of the hand (ie, the middle finger axis) is fractured: the ulnar condyle in the index finger and thumb and the radial condyle in the ring and small fingers.

NATURAL HISTORY

In developed countries, these fractures rarely go untreated, but they often are undertreated, given that their presentation may be interpreted as a “minimally displaced finger fracture.”
Similar to any PIP joint injury, lack of immobilization in full extension or prolonged immobilization will likely lead to a stiff finger.
If treated conservatively, displacement of the fracture, a common occurrence, will lead either to early painful arthritic changes or rotational malalignment on full flexion or both. The only potential exception is in children with significant growth potential remaining due to remodeling.⁵

PATIENT HISTORY AND PHYSICAL FINDINGS

A typical patient is a 24-year-old male basketball player who has sustained an angular impact to the finger from the ball.
A high index of suspicion is required when evaluating these patients. The patient often is still able to flex the finger, and the fracture line can be subtle. However, even nondisplaced fractures are prone to subsequent displacement.
Joint subluxation is an absolute indication for surgery and must be assessed carefully both radiographically and clinically.
With any fracture displacement, a rotational deformity of the finger may occur and is best assessed by either looking end on at the digit for isolated rotation of the nail plate compared to the adjacent fingernails or evaluating position with PIP flexion (FIG 2A).
Subtle joint depression may lead to angular deformity; this is best assessed by examining fingers in full extension (FIG 2B).

FIG 2 • A. End-on observation of the fingers can demonstrate subtle rotational deformities. B. Observation of the fingers in full extension can demonstrate subtle angular deformities caused by a displaced condyle.

IMAGING AND OTHER DIAGNOSTIC STUDIES

The fracture pattern dictates the type of fixation or treatment.
Multiple views should be obtained as needed to understand the geometry. Fluoroscopy often is helpful in obtaining precise views.
- Osteochondral fragments are often larger than they appear because the cartilage is radiolucent.
- Hidden fracture lines are common and are often not visualized until exposed at surgery.
Computed tomography (CT) is occasionally helpful.

NONOPERATIVE MANAGEMENT

Reports regarding the results of nonoperative treatment present conflicting results.
- Weiss and Hastings⁶ found five of seven nondisplaced fractures treated conservatively went on to displace and required surgery.
- In an 11-year follow-up study, using a functional outcome score, O’Rourke et al⁴ demonstrated several interesting points:
  - Twenty-seven percent of patients experienced joint aching in cold weather.
  - Four patients at 1-year follow-up had moderate pain and considered arthrodesis. However, by the time they got off the waiting list, their symptoms had subsided to the point that they declined surgery.
  - No patient had less movement in the joint at year 11 than at year 1.
  - Twenty-five percent of patients had continued improvement in ROM after 12 months follow-up.
  - Three patients with displaced bicondylar fractures treated conservatively had outcomes of good, fair, and poor, respectively.
  - Three patients with displaced unicondylar fractures treated conservatively had a good outcome; however, in O’Rourke et al’s⁴ discussion, they conclude that these fractures should be treated with reduction and fixation.
Operating on nondisplaced or minimally displaced fractures can be viewed in two ways:
- On the one hand, a percentage of patients would be subjected to a procedure that they did not need. Also, with close follow-up, if a fracture were to displace later, it could be addressed at that point, although it would require slightly more work to regain reduction and functional restoration.
- On the other hand, there is minimal morbidity in percutaneous pinning and that would minimize the likelihood of displacement in a fracture that often is unstable.
- Given the propensity for displacement and the potential functional difficulties with malunion, we recommend, at a minimum, percutaneous stabilization of most condylar fractures.
Several review texts suggest that coronal fractures of less than 25% of the joint surface with a stable congruent joint can be treated nonoperatively or with fragment excision. Although this may be true, there are few biomechanical or clinical outcomes data to support the statement.
A recent study examining the remodeling potential of distal condylar malunions in children demonstrated a substantial remodeling potential and functional ROM without pain. Although the series was small, malunions of unicondylar phalangeal fractures in children are likely best treated nonoperatively.⁶

SURGICAL MANAGEMENT

Preoperative Planning

Preoperative planning should be mindful of the goals of treatment of any articular fracture established by the AO:
- Anatomic reduction of the articular surface
- Restoration of stability
- Minimizing soft tissue injury
- Early mobilization
Access to a mini C-arm is highly advantageous.
- Fluoroscopic examination under anesthesia provides a good sense of joint stability and fracture fragment orientation.
- Fracture reduction, implant placement, and fracture stability are effectively evaluated fluoroscopically.