case_images: PMC10545460_01
case_images: Hip to ankle long-leg standing radiograph demonstrating bilateral symmetric 3  genu valgum.
case_images: CRIOR2023-3842443.001.jpg
case_images: PMC10545460_01_CRIOR2023-3842443.001.jpg
case_images: fig1
case_images: The patient reported 8/10 pain on the visual analog pain scale (VAS) with high impact activity; on physical examination, mild valgus alignment was demonstrated bilaterally (Figure 1); right quadriceps atrophy was noted with a persistent small effusion.
case_images: (a-c) Preoperative radiographs. (a) Anterior-posterior standing view with previous ACL reconstruction in the left knee and the Kellgren-Lawrence (KL) grade 2 right and grade 3 left findings. (b) Bilateral Merchant's views demonstrating lateral patellar tilt and mild osteophyte formation. (c) Right knee lateral view.
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case_images: PMC10545460_01_CRIOR2023-3842443.002.jpg
case_images: fig2
case_images: Radiographic evaluation with bilateral knee series demonstrated Kellgren-Lawrence- (KL-) 2 changes on the right and KL-3 findings on the left asymptomatic knee with retained screws from prior ACL reconstruction on the left (Figure 2(a)). Radiographic abnormalities were notable in the patellofemoral joint, demonstrating narrowing along the lateral facets bilaterally with mild lateral patellar tilt and subluxation on Merchant's view (Figure 2(b)). The Insall-Salvati ratio was within normal limits with a minor inferior pole patellar tendon enthesopathy on the lateral view of the right knee (Figure 2(c)).
case_images: (a, b) Open view 3.0 x 4.0 cm trochlear osteochondral defect. (c) Fresh OCA trochlear bulk allograft 3.0 x 4.0 cm, thickness 5-7 mm contoured. (d) Bulk allograft positioned in defect. (e) Chondral darts placed around the periphery to provide preliminary fixation. (f) Additional titanium 2.0 mm screws placed peripherally on the nonarticular margin of the allograft.
case_images: CRIOR2023-3842443.003.jpg
case_images: PMC10545460_01_CRIOR2023-3842443.003.jpg
case_images: fig3
case_images: Verification of a grade 4A trochlear lesion measuring 3 x 4 cm was made after arthrotomy (Figures 3(a) and 3(b)). We then measured the defect and used the sagittal saw to create an appropriately sized trochlear osteochondral allograft (Figure 3(c)). We then placed this into the trochlear defect to ensure anatomic fit (Figure 3(d)). Warsaw, IN) measuring 40 to 45 mm in length were placed at the four corners of the trochlear graft, stabilizing the trochlear graft in position (Figures 3(d)-3(f)).
case_images: Open view. (a) Lesion gauge used to size medial femoral condyle (MFC) lesion. (b) Guide pin centered in MFC lesion. (c) Reamed MFC lesion, 22.5 x 10 mm in diameter. (d) OP-1 implant preparation with normal saline prior to implantation. (e) OP-1 implant placed at the base of reamed defect. (f) 22.5 x 10 mm dowel graft impacted into position.
case_images: CRIOR2023-3842443.004.jpg
case_images: PMC10545460_01_CRIOR2023-3842443.004.jpg
case_images: fig4
case_images: The medial compartment demonstrated a 22.5 mm-diameter femoral condyle lesion (Figures 4(a) and 4(b)). The distal femur was exposed, and a central pin was placed into the medial femoral condylar lesion (Figures 4(a) and 4(b)). The lesion was reamed to a diameter of 22.5 mm, a depth of 8 mm at the peripheral edge, 7 mm at the proximal and distal edges, and 4 mm at the intercondylar notch area (Figure 4(c)). The OP-1 implant was mixed with 5 cc of sterile saline and mixed into a suspension (Figure 4(d)). The solution was gently applied to the base of the medial femoral condylar lesion (Figure 4(e)). We then impacted the dowel graft anatomically into a position (Figure 4(f)).
case_images: Postoperative AP view demonstrating screw fixation laterally and medially along the trochlear graft and maintained medial/lateral joint spaces after medial femoral condyle graft transplantation.
case_images: CRIOR2023-3842443.005.jpg
case_images: PMC10545460_01_CRIOR2023-3842443.005.jpg
case_images: fig5
case_images: We added an autologous bone graft saved from site preparation and applied it around the periphery of the trochlear graft (Figure 5). We then exposed the patella and debrided osteophytes from the periphery of the patella.
case_images: At time of ACL reconstruction 2 years following transplantation of medial 22.5 x 10 mm dowel allograft with maintained articular cartilage surface and excellent incorporation.
case_images: CRIOR2023-3842443.006.jpg
case_images: PMC10545460_01_CRIOR2023-3842443.006.jpg
case_images: fig6
case_images: Direct arthroscopic visualization of the trochlear (Brittberg 12/12) and medial femoral (Brittberg 11/12) lesions demonstrated excellent incorporation of the grafts and no signs of delamination (Figure 6).
case_images: Two-year postoperative MRI. (a) Axial metal artifact reduction sequence (MARS) image demonstrates previous trochlear osteochondral allograft well integrated with intact articular cartilage. (b) T2 mapping axial image with thinning of medial and lateral patellar facets. (c) Additional axial image. (d) Sagittal MARS proton density-fat suppression image demonstrating maintained trochlear implant congruity and bone incorporation; slight thinning at the inferior patellar articular cartilage is demonstrated as well.
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case_images: PMC10545460_01_CRIOR2023-3842443.007.jpg
case_images: fig7
case_images: MOCART 2.0 scores of 80 and 90 were noted, respectively (Figures 7(a)-7(d)).
case_images: Four-year postoperative radiographs demonstrating excellent bone incorporation and maintained joint spaces with continued KL-2 grade on the right side. (a) Bilateral PA weightbearing. (b) Bilateral Merchant's view. (c) Lateral right knee.
case_images: CRIOR2023-3842443.008.jpg
case_images: PMC10545460_01_CRIOR2023-3842443.008.jpg
case_images: fig8
case_images: Radiographs were obtained, demonstrating excellent bone incorporation of the trochlear and medial femoral grafts (Figures 8(a)-8(c)).
case_images: Four-year postoperative MRI. (a) Axial metal artifact reduction sequence (MARS) image demonstrates previous trochlear osteochondral allograft well integrated with intact articular cartilage. (b) T2 mapping axial image with maintained patellofemoral articular cartilage. (c) Sagittal MARS image with well-incorporated medial femoral allograft and preserved articular continuity. (d) Sagittal T2 mapping image demonstrating intact articular cartilage surface at medial femoral condyle allograft.
case_images: CRIOR2023-3842443.009.jpg
case_images: PMC10545460_01_CRIOR2023-3842443.009.jpg
case_images: fig9
case_images: This allowed additional imaging of the trochlear and medial femoral OCA grafts, demonstrating excellent bone incorporation of both grafts and maintaining articular surfaces with no signs of delamination 4 years following transplantation (Figures 9(a)-9(d)).
case_images: Eight-year postoperative radiographs. (a) Merchant's view demonstrating trochlear implant incorporation with maintained patellofemoral joint space on the right (KL-2) but progression of disease on the left (KL-4). (b)Posterior-anterior Rosenberg view demonstrating maintained medial/lateral joint spaces on the right (KL-2) with left knee progression (KL-4). (c) Right knee lateral radiograph demonstrating excellent trochlear allograft incorporation.
case_images: CRIOR2023-3842443.010.jpg
case_images: PMC10545460_01_CRIOR2023-3842443.010.jpg
case_images: fig10
case_images: Radiographic evaluation 8 years following OCA transplantation demonstrated excellent bone incorporation of the trochlear and medial femoral grafts; interestingly, the right knee maintained a KL-2 grade, while the left knee demonstrated deterioration to a KL-4 grade (Figures 10(a)-10(c)).