No complications reported using microfracture for talar cartilage

Among the procedure’s advantages at three years postop are no malleolar nonunions or ankle arthritis.

Issue: September 2004

Short-term results from a prospective study where microfracture was used to restore talar cartilage showed the technique was effective for repairing osteochondral and degenerative lesions and produced good functional outcomes.

Hajo Therman [photo] Hajo Thermann finds the chondrocyte matrix seen arthroscopically is similar after microfracture and chondrocyte transplantation.

During the International Cartilage Repair Society 5th Symposium, Christopf Becher, MD, a fellow at the ATOS Clinic in Heidelberg, Germany, presented results of procedures done by Hajo Thermann, MD, which were followed up for 38 months mean. “This is a pure arthroscopic technique that we do with the microfracture and we haven’t had any side effects from the technique,” Thermann told Orthopedics Today.

This osteochondral lesion (top) typifies ones that Hajo Thermann treated with microfracture in this series. Outcomes tended to be better with them than degenerative chondral lesions. Thermann used a superior medial approach to perform microfracture of talar lesions using a swan-neck awl to make the perforations perpendicular to the cartilage surface (bottom).

COURTESY OF HAJO THERMANN

The fact that there were no complications in the series of 39 patients reported on, which now includes 40 patients with a minimum follow-up of two years, provides evidence that microfracture is superior to autologous chondrocyte transplantation (ACT) for the same indication, he said.

With microfracture, which Thermann does as a first-line treatment after patients fail conservative care, “we have no problems with complications, nonunions in the malleolus, osteoarthritis in the medial gutter of the ankle. So this is another real advantage.”

More effective for osteochondral lesions

There were 25 men and 14 women (average age, 37 years) in the study. Twenty-six patients had osteochondral lesions and their results were better than for the 13 patients with degenerative chondral lesions. The seven patients who were older than age 50 had slightly better results.

Evaluations were done preoperatively and at three, six, 12, 24 and 36 months postoperatively using the Hannover scoring system that Thermann developed and the Visual Analog Scale (VAS) (0=poor, 10=excellent). Thermann said the Hannover system has been validated. It was published a number of times and used by prominent investigators in the field.

Results were also followed using MRI scans done initially to identify the lesion and subsequently to track cartilage regeneration at all follow-up time points. In addition, several patients underwent postoperative arthroscopic assessments. Three patients were lost to follow-up. Two of them had total ankle arthroplasty at 15 and 28 months post-treatment.

Based on the Hannover scores, 89% of patients had good or excellent results at the three-year follow-up compared to 81% at two years and 85% at one year. Based on the average VAS scores, pain improved from 3.70 preoperatively to 8.01 at final follow-up. Function, which was 3.53 preoperatively, improved to 7.59 at three years. Patient satisfaction improved to 7.48 from 2.41 preoperatively.

Thermann attributed these results in part to the rehabilitation program his patients used, which he described as cartilage massage.

“We haven’t had any side effects from the technique.”
— Hajo Thermann

“This is a very good technique, in my opinion, to enhance regeneration and form a good regenerate into fibrocartilage,” he said.

Patients were prescribed use of a continuous passive motion (CPM) machine at home for four to six hours a day for four weeks, which Thermann said is gentle on the newly formed cartilage layer. If a revision is needed, Thermann typically uses ACT but said he has encountered some problems with its biological transformation. The other problem is its cost, which in Germany is approximately 6992 euros ($8637). “Microfracture is more cost effective,” he said. Thermann said his paper has been accepted for publication in Foot & Ankle International.

For more information:

Becher C, Thermann H. The microfracture technique in the treatment of chondral lesions of the talus — 3 years follow up of a prospective study. #594. Presented at the International Cartilage Repair Society 5th Symposium. May 26-29, 2004. Gent, Belgium.