Search

Background: Reduced viability in the deepest zones of osteochondral allografts (OCAs) can weaken the subchondral interface, potentially increasing the risk of failure. This reduction may result from nutritional imbalances due to uneven media distribution or interference from bone marrow elements. Purpose: To investigate whether culturing OCAs using a rotary shaker or removing the bone marrow elements would increase graft cellular viability. Study Design: Controlled laboratory study. Methods: Bovine osteochondral explants were stored for 28 days at 4°C under 3 different conditions (n = 6 explants per group): static (control group), rotary shaker at 150 rpm (shaker group), and static after removal of bone marrow elements using a Waterpik device (Waterpik group). Chondrocyte viability was assessed using live/dead staining across the entire tissue and in each zone (superficial, middle, deep). Subchondral bone viability was assessed using TUNEL (terminal deoxynucleotidal transferase–mediated biotin–deoxyuridine triphosphate nick-end labeling) staining to detect apoptotic cells. Results: Both shaker (64.2%; P =.010) and Waterpik (65.6%; P =.005) conditions showed significantly higher chondrocyte viability compared with control (49.8%). When samples were analyzed by zone, the shaker and Waterpik groups displayed higher cellular viability at the middle zone (shaker = 60.6%, P <.001; Waterpik = 56.1%, P <.001) and deep zone (shaker = 63.1%, P =.018; Waterpik = 61.5%, P =.025) than the control group (25.6% at middle zone; 32.8% at deep zone). Additionally, shaker (56.7%; P =.018) and Waterpik (51.4%; P =.007) groups demonstrated a lower percentage of apoptotic cells in subchondral bone compared with control (88.0%). No significant differences were observed between the shaker and Waterpik groups in any of the analyses. Conclusion: Both rotary shaking and removal of bone marrow elements during storage of osteochondral explants led to higher chondrocyte viability at the middle and deep zones of the graft compared with the static storage condition. Enhancing nutrition delivery to the graft could improve its quality, potentially improving outcomes of OCA transplantation. Clinical Relevance: The use of a rotary shaker or the removal of bone marrow elements may significantly improve the culture conditions, increasing graft viability and integrity after OCA storage. [ABSTRACT FROM AUTHOR]

Background: Coronal and sagittal malalignment of the knee are well-recognized risk factors for failure after anterior cruciate ligament (ACL) reconstruction (ACLR). However, the effect of axial malalignment on graft survival after ACLR is yet to be determined. Purpose: To evaluate whether increased tibiofemoral rotational malalignment, namely, tibiofemoral rotation angle (TFA) and tibial tubercle–trochlear groove (TT-TG) distance, is associated with graft failure after ACLR. Study Design: Cohort study; Level of evidence, 3. Methods: In this retrospective matched control study of a single center's database, 151 patients who underwent revision ACLR because of graft failure (ACLR failure group, defined as symptomatic patients with anterior knee instability and an ACL graft tear appreciated on magnetic resonance imaging [MRI] and confirmed during arthroscopic surgery) were compared with a matched control group of 151 patients who underwent primary ACLR with no evidence of failure after ≥2-year follow-up (intact ACLR group). Patients were matched by sex, age, and meniscal injury during primary ACLR. Axial malalignment was assessed on preoperative MRI through the TFA and the TT-TG distance. Sagittal alignment was measured through the posterior tibial slope on MRI. The optimal TFA cutoff associated with graft failure was identified by a receiver operating characteristic curve. The Kaplan-Meier curve with log-rank analysis was performed to evaluate the influence of the TFA on ACLR longevity. Results: The mean age was 25.7 ± 10.4 years for the ACLR failure group and 25.9 ± 10.0 years for the intact ACLR group. Among all the included patients, 174 (57.6%) were male. In the ACLR failure group, the mean TFA was 5.8°± 4.5° (range, −5° to 16°), while it was 3.0°± 3.3° (range, −3° to 15°) in the intact ACLR group (P <.001). Neither the TT-TG distance nor the posterior tibial slope presented statistical differences between the groups. The receiver operating characteristic curve suggested an optimal TFA cutoff of 4.5° for graft failure (area under the curve = 0.71; P <.001; sensitivity, 68.2%; specificity, 75.5%). Considering this a threshold, patients who had a TFA ≥4.5° had 6.6 times higher odds of graft failure compared with patients with a TFA <4.5° (P <.001). Survival analysis demonstrated a 5-year survival rate of 81% in patients with a TFA <4.5°, while it was 44% in those with a TFA ≥4.5° (P <.001). Conclusion: An increased TFA was associated with increased odds of ACLR failure when the TFA was ≥4.5°. Measuring the TFA in patients with ACL tears undergoing reconstruction may inform the surgeon about additional factors that may require consideration before ACLR for a successful outcome. [ABSTRACT FROM AUTHOR]