Do you have pain in the back of your ankle when walking, or pointing the
toes? Do you play sports, and notice that you have pain when kicking a
ball or jumping? Does your ankle swell and cause pain? Is the back of
the ankle tender to the touch? If so, you may want to talk to an
orthopedic surgeon about os trigonum syndrome.
The os trigonum is a bony point of the posterolateral talus—meaning
it’s an extra bone fragment, or bone spur, that sits on the back
of the ankle near the heel bone that can cause pain and irritation with
activity. This occurs in approximately 10-25% of the population. In most
of us, this part of the ankle fuses together when we are between the ages
of 8 and 13 years old. However, sometimes it does not fuse. We also see
this in the form of a stress fracture or after an injury, where the foot
is plantarflexed—toes and ankle pointed down toward the floor.
Most often people don’t have symptoms, but over time or with injury
it can cause discomfort and pain. Originally described in dancers, here
in Wyoming, I see this most commonly in oil rig workers, construction
workers, coal miners and other demanding, very physical jobs.
Diagnosis of os trigonum syndrome begins with a thorough history and examination
of the foot and ankle at
Powder River Orthopedics & Spine, complete with
X-rays. To confirm the diagnosis, an
MRI is usually ordered. The X-ray will show the bony spur (os trigonum) or
help distinguish it from a fractured talus bone in the foot. The MRI can
identify a tear in the fibrous tissue, or a stress fracture of the os—it
will light up in a white color, indicating that there is irritation at
the os trigonum.
Treatment usually begins with simple steps: rest, ice, non-steroidal anti-inflammatory
medications, physical therapy and/or a walking boot to restrict painful
ankle movement—in children, we often start with casting to decrease
Physical therapy has helped many of my patients out and they have been able to avoid surgery.
If rest and activity modifications fail to relieve the symptoms, a surgery
can be considered to remove the abnormal bone in the back of the ankle.
I will perform a subtalar arthroscopy and os trigonum excision. This involves
placing a camera inside the subtalar joint and shaving the scar tissue
on the posterior joint and removing the loose bony fragment (os trigonum).
This is an outpatient surgery and I let my patients be fully weightbearing
in a boot after surgery. Physical therapy can often be helpful in the
recovery phase and sutures will be removed between two to four weeks.
Patients can often return to normal activity after four to six weeks of
treatments, as long as ankle movements are no longer painful.
Dr. Robert Grunfeld is a board-certified orthopedic surgeon at
Powder River Orthopedics and Spine who specializes in foot and ankle procedures. The Board-certified physicians
at PROS take an innovative and comprehensive approach to the treatment
of acute and chronic orthopedic pain. Have your procedure in our modern
operating rooms at
Campbell County Memorial Hospital or
Powder River Surgery Center. See the PROS for:
- General orthopedic surgery
- Joint replacement surgery: shoulder, hip, knee and ankle
- Shoulder, elbow, hand and wrist surgery
- Sports Medicine
- Spine surgery and injections, including minimally invasive procedures
- Bunions and great toe arthritis procedures
- Foot and ankle surgery
- Trauma and fracture care
- Workplace injuries
For a consultation, call 307.686.1413 or visit
PROS is a Campbell County Medical Group
Clinic with Campbell County Health.