1. Introduction

a. Mark Incision

b. Apply Finger Tourniquet

2. Patient Preparation

3. Incision

4. Opening and Exposure of Joint

5. Debridement of Articular Cartilage down to Subchondral Bone

6. Confirmation of Adequate Debridement and Alignment via Fluoroscopy

7. Guidewire Insertion

8. Measurement for Screw Length

9. Screw Placement and Compression of Joint

10. Confirmation of Final Screw Position

a. Excision of Redundant Skin Proximally

11. Closure with Tenodermodesis Technique

12. Post-op Remarks

Abstract
Osteoarthritis commonly impacts the finger distal interphalangeal (DIP) joints. The prevalence of DIP joint arthritis is high, with more than 60% of individuals older than 60 having DIP joint arthritis. Operative treatment for arthritis of the DIP joint is indicated for pain, deformity, dysfunction, and instability in patients who are recalcitrant to conservative measures. Arthrodesis, or the fusion, of the DIP joint is a widely accepted surgical treatment for DIP joint arthritis. Several surgical techniques have been historically described, with headless compression screw (HCS) fixation being a particularly common technique because of its advantages, including reliable compression, rigid fixation, lack of prominence, and no need for removal. This video demonstrates arthrodesis using HCS for arthritis in the right ring finger DIP joint.

<h4>CHAPTER 1</h4>

<p>Distal interphalangeal joint arthritis,
or DIP joint arthritis,
is second only to thumb basal joint arthritis
in terms of the most symptomatic arthritis of the hand
often necessitating surgical intervention.
The technique being demonstrated here
is an arthrodesis of the distal interphalangeal joint.
The indication for this technique
is pain, deformity, and dysfunction.
The technique being demonstrated here
is being performed under just local anesthesia
in a wide-awake hand surgery fashion.</p>

<h4>CHAPTER 2</h4>

<p>You'll notice the patient here
has advanced arthritic changes of the ring finger DIP joint
and has previously undergone
index and middle finger DIP arthrodesis.
Now the ring finger will be performed today.
The technique requires the use of a headless compression screw.
Here a 2.4 headless compression screw will be used.</p>

<p>Because the anesthesia being used is only a digital block
with minimal lidocaine and epinephrine
in the surgical site directly,
a finger tourniquet is also being applied.</p>

<h4>CHAPTER 3</h4>

<p>The exposure is achieved entirely dorsally,
so the incision is placed directly
across the DIP joint dorsally.
The incision is placed full thickness
through the skin, tendon, and the dorsal joint capsule.</p>

<h4>CHAPTER 4</h4>

<p>The joint is then opened,
and the collaterals are also taken down
to fully expose the joint.
Care is taken not to injure the flexor tendon
deep to the joint on the volar side.</p>

<h4>CHAPTER 5</h4>

<p>With the DIP joint fully exposed
and the articular surface of the middle phalanx's head
and the distal phalanx space exposed,
a rongeur is used to debride off the articular cartilage
down to subchondral bone.
I find it as easier
to debride the middle phalanx's head first
before progressing to the distal phalanx space,
because once the middle phalanx has been debrided
the distal phalanx space is better exposed.
Generally, that distal side
is harder to debride of articular cartilage.
It is often helpful to elevate the soft tissue
off of the dorsum of the distal phalanx space as shown here,
even extending the flap distally
around the nail may also be helpful
to fully expose the base to get the articular cartilage off.</p>

<h4>CHAPTER 6</h4>

<p>Once debrided, the fluoroscopy machine can be brought in
to confirm adequate debridement down to subchondral bone
as well as to make sure adequate alignment has been restored
and any deformity corrected.
This should be checked on both the PA and lateral views.
Extra osteophytes that have been left behind
can also be assessed now and debrided away.</p>

<h4>CHAPTER 7</h4>

<p>Once satisfied with the joint debridement
and alignment of the arthrodesis site,
the guidewire for the headless compression screw
is prepared to be inserted.
I recommend using an inside-out technique
where the guidewire is first placed across
the distal phalanx in the desired center, center position
and then reversed into the middle phalanx.
The inside-out technique is being shown here.
Once happy with the alignment of the guidewire,
that guidewire is then removed, flipped around,
so that the blunt end is then directed
into the distal phalanx
until only a bit of the sharp end is showing
within the arthrodesis site.
This will then allow the sharp end
to be then placed retrograde into the middle phalanx
under direct visualization.
Here, reversal of the pin and alignment
of the arthrodesis site is demonstrated on fluoroscopy.
Once satisfied with the alignment,
the pin can then be advanced into the middle phalanx.
Here the pin can be seen being advanced retrograde
back into middle phalanx
and then confirmed on fluoroscopy.</p>

<h4>CHAPTER 8</h4>

<p>Next, the screw length is measured.
I generally find the available cannulated depth gauges
to be unhelpful,
because the length of the screws should be such
that it is countersunk below the head of the distal phalanx
and should end within the isthmus of the middle phalanx.
So oftentimes, what is more helpful
is simply measuring a screw on fluoroscopy
to fit that desired length.</p>

<h4>CHAPTER 9</h4>

<p>Next, the cannulated drill is placed across the guidewire
to create the path for the headless compression screw,
and finally, the screw is placed across the guidewire
and advance into the distal phalanx in a retrograde fashion.
To achieve maximal compression across the arthrodesis site,
I recommend compressing the arthrodesis site externally
to achieve what I refer to as macro-compression
and then allow the headless compression screw
to achieve a micro-compression.</p>

<h4>CHAPTER 10</h4>

<p>Here, final position of the screw is confirmed
making sure that the screw head is adequately countersunk
within the distal phalanx,
and that there is good contact and compression
without gapping across the arthrodesis site.
Also, prior to washing the wound and closure,
restoration of normal rotation of the finger
should also be confirmed
with active flexion of the finger by the patient
to make sure that the alignment is appropriate.</p>

<h4>CHAPTER 11</h4>

<p>If there is excessive redundancy of the skin,
the proximal aspect of the skin can be excised
to improve the closure.
Also, I find it helpful to repair the skin
in a tenodermodesis technique.
That involves repairing the skin
and the underlying extensor tendon in one throw.
That helps bulk up the closure dorsally
and cover the arthrodesis site.
I use simple 4-0 nylon sutures as demonstrated here.
Once closed, a soft dressing is applied.
The patient is allowed to move the finger immediately.
Obviously, the the DIP joint will not move,
but early motion overall is encouraged.
The dressing can be removed in two days,
and the sutures can be removed in two weeks.</p>

<h4>CHAPTER 12</h4>

<p>I typically check radiographs again
at two weeks and 12 weeks postoperatively
to confirm healing of the arthrodesis site.
The patient is allowed to return to activities
as tolerated immediately.
The last thing to discuss is a word of warning.
Sometimes fingers can be larger,
and a larger screw can be used.
In this case, a 2.4 screw was used.
More commonly and more troublesome
is that some fingers are smaller
and have difficulty accepting a headless screw.
I would refer you to a study published
by one of our former fellows
who looked at the diameter of screws
and found that some fingers require smaller screws
such as closer to 2.0 to meet the diameter
of the canal of the distal phalanx and middle phalanx.</p>


Watch this narrated surgical video of an arthrodesis of the DIP joint of the right ring finger for arthritis performed by Dr. Asif Ilyas a the Rothman Institute.

Rothman Institute