Residency Insight -- A PRESENT Podiatry eZine

Case Conclusion: Sinus Tarsitis following Inversion Injury

Ryan Fitzgerald, DPM
PRESENT RI Associate Editor
Hess Orthopedics &
Sports Medicine
Harrisonburg, Virginia

There have been a couple of excellent responses regarding this challenging case via the eTalk thread on this topic at PRESENT Podiatry!

If you did not get a chance to read part 1 of this case study, or would just like to review, you can follow this link to read the eZine.

Considering the patient’s persistent symptoms, but a general failure of more conservative modalities, the patient was initially started on a course of oral anti-inflammatory medications as well as physical therapy. When this failed to resolve her symptoms, the patient was immobilized for several weeks in a cam-walker. She related that her symptoms in the area of her sinus tarsi improved while in the boot, but that she had a recurrence of symptoms upon removal of the boot.

At this point, considering the failure of more conservative modalities, an MRI was obtained to evaluate for the possibility of soft tissue or osseous injury that could not be appreciated on the plain-film radiographs. The MRI demonstrated increased signal intensity within the sinus tarsi consistent with an inflammatory response, however there was no obvious pathology identified.

At this point a diagnostic sub-talar joint injection was performed through the sinus tarsi to confirm that all of the patients symptoms were, indeed, coming from this joint. With the injection, the patient’s symptoms fully resolved for the duration of the local anesthesia, and for the 12 hours following the injection she was able to return to full activity.

Considering the response to the diagnostic injection, and the failure of previous more conservative modalities, the possibility of performing a subtalar joint arthroscopy was broached to be both diagnostic and potentially therapeutic if pathology could be identified. Consent was obtained and the patient was brought to the operating room.

Figure 1. A-D: Selected images from the arthroscopy can be seen above, which demonstrate the development of an interosseous ligament tear (images A, C) with the development of a meniscoid body with is creating posterior facet impingement (image D). Arthroscopic debridement was performed, and these lesions were removed. (Follow this link or click on the image for a larger view.)

Post operatively, the patient was placed NWB in a removable cast-walking boot for approximately two weeks, with partial weight bearing and passive ROM initiated at during week three.

The patients pain symptoms resolved with this procedure, and she is currently at one year, pain free, with no further issues.

Discussion

While subtalar joint arthroscopy may seem esoteric and technically demanding, it can be a useful modality to address Subtalar joint pathology. Like all arthroscopy, there is a learning curve, but it is not significantly more difficult than ankle arthroscopy, indeed, in many ways it is much simpler. Ultimately, the more you practice arthroscopy, the better arthroscopist you will become.

Figure 2. CENTRAL PORTAL (middle portal): When considering performing a subtalar joint arthroscopy, it is important to know the pertinent anatomy, as well as the potential pathology one may encounter through the scope — this will aid in patient selection as well as in the development of a surgical plan. (Follow this link or click on the image for a larger view.)

As always, patient selection is extremely important, and it is important to establish realistic expectations with the patient prior to surgery. If you can accomplish these tasks, subtalar joint arthroscopy can become a valuable part of your armamentarium in the management of lower extremity disorders.

We love hearing from you. I enocuare all of our readers to participate in the eTalk thread on this topic — and post your thoughts, pearls, and perspectives regarding this (or any other) interesting case.