A computer assisted surgical technique for retrograde autologous osteochondral grafting in talar osteochondritis dissecans (OCD): a cadaveric study

Abstract

This study describes a new method for the treatment of osteochondritis dissecans (OCD) in the medial talar dome. Ten cadaveric lower extremities were used to develop and evaluate a retrograde osteochondral grafting technique applying computer-assisted surgery. With the help of a computed tomography (CT)-based navigation system, a guide wire was placed from the lateral talar process into the posteromedial talar trochlea where OCD lesions are predominantly located. Cannulated reamers and arthroscopic shavers were used for the preparation of the recipient hole. The grafts, with diameters of 4.5 mm, 6.5 mm or 8.5 mm were harvested from the lateral femoral trochlea and inserted in a retrograde fashion. The last five cadavers were analyzed for accuracy of surface reconstruction and graft stability. For this purpose a medial malleolar osteotomy and a CT scan was performed. We found steps in the joint surface to range from 0.5 mm to 1.5 mm (mean 0.9 mm, SD 0.4) with the graft always below the surrounding cartilage. Graft subsidence occurred at an applied force of 26.4 +/- 4.6 N. This study indicates that osteochondral cylinders can be inserted in a retrograde fashion to reconstruct the posteromedial talus. Good surface congruency and sufficient graft stability can be achieved.

CT-Guided Percutaneous Retrograde Drilling of Talar Osteochondrosis Dissecans: A Case-Report

“…Retrograde drilling using fluoroscopy has been described in other studies [7,9,10], as well as retrograde drilling using a cast and a CT navigation system [5,6,8,15], with good success, but all included arthroscopic examination of the joint. Bail et al [16] described a novel method for retrograde drilling using MRI.…”

“…Retrograde drilling, which leaves the cartilage unharmed, has only been described in a few studies [5][6][7][8][9][10], but success rates are high: 81-100% [8,9,11]. Most studies use arthroscopy as a navigation method for retrograde drilling, but fluoroscopy is used for navigation as well [7,9,10].…”

Navigierte retrograde Anbohrung bei Osteochondrosis dissecans (OCD) des Talus

“…Dafür ist aber häufig ein ausgedehnter Zugang mit Osteotomie nötig [19]. Zur genaueren und weniger schädigenden retrograden Bohrung wurde die Computertomographie (CT)-basierte computerassistierte Chirurgie (CAS)-gesteuerte Technik beschrieben [2,7,10,18]. Die derzeit in Anwendung befindlichen dreidimensionalen CT-und Röntgenbildverstärker (BV-2-D)-basierten Navigationssysteme sind in Ihrer Flexibilität (CT) und Visualisierung (BV-2-D) sehr eingeschränkt [13,15].…”

“…Die Spongiosa kann sehr leicht mit einem manuell geführten 3,5-mm-Bohrer eingestößelt werden Abb. 10 8 Arthroskopische Abschlussbeurteilung. Hierbei insbesondere Überprüfung der Knorpeloberfläche, die in diesem Fall intakt und westlich weniger eindrückbar war als vor der Intervention.…”

Automated Planning of Computer Assisted Mosaic Arthroplasty

“…The planning consisted of using patient images to manually choose a path for the surgical drill. Another study using the talus found better plug harvesting and placement with computer assist [13]. Computer planning has also been used to match plugs from the femoral condyles to defects in the talus [14].…”