PURPOSE: This study aimed to investigate anterior knee symptoms in patients who underwent anterior cruciate ligament (ACL) reconstruction using bone-patellar tendon-bone (BPTB) graft followed by implantation of a beta-tricalcium phosphate (β-TCP) block as a bone void filler. MATERIALS AND METHODS: We retrospectively reviewed 84 cases of synthetic bone grafting using a β-TCP block for the patellar bone defect in ACL reconstruction with a BPTB autograft. Computed tomography of the operated knee was performed immediately after the surgery to evaluate whether the grafted β-TCP block protruded forward from the anterior surface of the patella. On the basis of the results, the cases were divided into a protrusion group (n=31) and a non-protrusion group (n=53). Anterior knee symptoms at 12 months postoperatively and absorption of the grafted β-TCP block were compared between the two groups. RESULTS: Except for patellofemoral crepitus, there was no significant difference in anterior knee symptoms between the two groups (p>0.05). The incidence of patellofemoral crepitus was significantly lower in the protrusion group than in the non-protrusion group (p=0.027). The groups showed no significant difference in β-TCP absorption. CONCLUSIONS: The present study demonstrated that the protrusion of β-TCP that was used as a bone void filler had no adverse effects.
Absorption ; Anterior Cruciate Ligament Reconstruction ; Anterior Cruciate Ligament ; Autografts ; Bone Transplantation ; Bone-Patellar Tendon-Bone Grafts ; Humans ; Incidence ; Knee ; Patella ; Retrospective Studies ; Tissue Donors ; Transplants

Anterior talofibular ligament (ATFL) injuries are the most common cause of ankle sprains. To ensure anatomically accurate surgery and ultrasound imaging of the ATFL, anatomical knowledge of the bony landmarks around the ATFL attachment to the distal fibula is required. The purpose of the present study was to anatomically investigate the ATFL attachment to the fibula with respect to bone morphology and attachment structures. First, we analyzed 36 feet using microcomputed tomography. After excluding 9 feet for deformities, the remaining 27 feet were used for chemically debrided bone analysis and macroscopic and histological observations. Ten feet of living specimens were observed using ultrasonography.We found that a bony ridge was present at the boundary between the attachments of the ATFL and calcaneofibular ligament (CFL) to the fibula. These two attachments could be distinguished based on a difference in fiber orientation. Histologically, the ATFL was attached to the anterodistal part of the fibula via fibrocartilage anterior to the bony ridge indicating the border with the CFL attachment. Using ultrasonography in living specimens, the bony ridge and hyperechoic fibrillar pattern of the ATFL could be visualized. We established that the bony ridge corresponded to the posterior margin of the ATFL attachment itself. The ridge was obvious, and the superior fibers of the ATFL have directly attached anteriorly to it. This bony ridge could become a valuable and easy-to-use landmark for ultrasound imaging of the ATFL attachment if combined with the identification of the fibrillar pattern of the ATFL.