Tackling the Challenges of Graft Healing After Anterior Cruciate Ligament Reconstruction—Thinking From the Endpoint

Anterior cruciate ligament (ACL) tear is common in sports and accidents, and accounts for over 50% of all knee injuries. ACL reconstruction (ACLR) is commonly indicated to restore the knee stability, prevent anterior–posterior translation, and reduce the risk of developing post-traumatic osteoarthritis. However, the outcome of biological graft healing is not satisfactory with graft failure after ACLR. Tendon graft-to-bone tunnel healing and graft mid-substance remodeling are two key challenges of biological graft healing after ACLR. Mounting evidence supports excessive inflammation due to ACL injury and ACLR, and tendon graft-to-bone tunnel motion negatively influences these two key processes. To tackle the problem of biological graft healing, we believe that an inductive approach should be adopted, starting from the endpoint that we expected after ACLR, even though the results may not be achievable at present, followed by developing clinically practical strategies to achieve this ultimate goal. We believe that mineralization of tunnel graft and ligamentization of graft mid-substance to restore the ultrastructure and anatomy of the original ACL are the ultimate targets of ACLR. Hence, strategies that are osteoinductive, angiogenic, or anti-inflammatory should drive graft healing toward the targets. This paper reviews pre-clinical and clinical literature supporting this claim and the role of inflammation in negatively influencing graft healing. The practical considerations when developing a biological therapy to promote ACLR for future clinical translation are also discussed.

Non-Conventional Tendon Advance for injuries in zones I and II New Surgical Technique

Once a primary suture of flexor tendon in zone II of Verdan is unable to be performed, or in those cases in which a re-rupture of a primary tenorraphy occurs, the tendon graft is the goldstandard option.

Double-Layered Quadriceps Tendon Autografts Provide Lower Failure Rates and Improved Clinical Results Compared With Hamstring Tendon Grafts in Revision ACL Reconstruction

Background: We developed a quadriceps-tendon graft technique using a double-layered, partial-thickness, soft tissue quadriceps tendon graft (dlQUAD) for anterior cruciate ligament reconstruction (ACLR). This technique allows simple femoral loop button fixation and a limited harvest depth of the quadriceps tendon. Purpose: To evaluate the outcome of patients undergoing revision ACLR using the dlQUAD technique compared with a hamstring tendon graft (HT). Study Design: Cohort study; Level of evidence, 3. Methods: A total of 114 patients who underwent revision ACLR between 2017 and 2018 were included in this retrospective case series. At a mean follow-up of 26.9 ± 3.7 months (range, 24-36), 89 patients (dlQUAD: n = 43, HT: n = 46) were clinically examined. In addition, patients completed the Lysholm score, Tegner activity scale, subjective International Knee Documentation Committee (IKDC), Knee injury and Osteoarthritis Outcome Score, and visual analog scale (VAS) for pain. Postoperative failure of the revision ACLR was defined as a side-to-side difference (SSD) in Rolimeter testing ≥5 mm or a pivot-shift grade of 2 or 3. Results: Nine patients (10.1%) were identified with a failed revision ACLR. There was a significantly lower failure rate with dlQUAD versus the HT group (2.3% vs 17.4%; P = .031). The mean postoperative SSD was significantly less in the dlQUAD group (1.3 ± 1.3 mm [range, 0-5] vs 1.8 ± 2.2 mm [range, 0-9]; P = .043). At the latest follow-up, Tegner and IKDC scores significantly improved in the dlQUAD group compared with the HT group (Tegner: 5.8 ± 1.8 vs 5.6 ± 1.5; P = .043; IKDC: 83.8 ± 12.2 vs 78.6 ± 16.8; P = .037). The pain VAS score was also significantly reduced in the dlQUAD group compared with the HT group (0.9 ± 1.1 vs 1.6 ± 2.0; P = .014). Conclusion: The dlQUAD and HT techniques both demonstrated significant improvement of preoperative knee laxity and satisfactory patient-reported outcome measures after revision ACLR. Compared with the HT grafts, the dlQUAD technique showed lower failure rates and small increases in Tegner and IKDC scores.

Arthroscopic one-tunnel transosseous reconstruction of chronic triangular fibrocartilage complex foveal tears: outcomes in 12 patients

We report the surgical method and outcomes of a simple arthroscopic-assisted technique of repairing triangular fibrocartilage complex (TFCC) foveal injuries in 12 patients with chronic distal radioulnar joint instability. An ulnar transosseous tunnel was created with its distal exit point located 3 to 4 mm radial to the fovea. A tendon graft was cut into two parts, and both were then passed through the bone tunnel to secure the radioulnar ligament remnants back to the fovea in a ‘V’ shape configuration. At the final follow-up of 13 to 26 months (average 21), all patients had a reduction of wrist pain, with the mean visual analogue scale dropped from 4.6 to 1.6 out of 10. The distal radioulnar joint was completely stable in nine patients and had improved stability in three patients. The mean Mayo modified wrist scores improved from 72 to 89, and the clinical outcomes were excellent in four patients, good in seven and fair in one. No major surgical complications occurred. This simple arthroscopic one-tunnel transosseous approach is effective for chronic foveal tears of the TFCC with intact radioulnar ligament remnants. Level of evidence: IV

Continuous-Loop Tape Technique Has Greater Stiffness and Less Elongation Compared With Tied-Suture Fixation of Full-Thickness All–Soft Tissue Quadriceps Tendon Autografts

Background: Many graft fixation techniques are utilized for full-thickness soft tissue quadriceps tendon autografts during anterior cruciate ligament reconstruction (ACLR). Purpose: To determine the tensile properties of all–soft tissue quadriceps tendon graft fixation using a tied-suture versus continuous-loop tape technique. It was hypothesized that the continuous-loop tape technique would have less cyclic elongation and greater ultimate load to failure and stiffness compared with a commonly used tied-suture technique. Study Design: Controlled laboratory study. Methods: Sixteen fresh-frozen human knee specimens were used to harvest a full-thickness all–soft tissue quadriceps tendon graft; half were secured using a Krackow suture technique with 2 braided sutures, and half were secured using a continuous-loop tape suspensory fixation button with a rip-stop stitch. Cyclic and permanent elongation, toe- and linear-region stiffness, and ultimate load were determined. Statistical analysis was performed at P <.05. Results: The tied-suture fixation group demonstrated significantly higher permanent elongation (11.7 ± 3.6 vs 4.2 ± 1.0 mm, P < .001) and cyclic elongation (5.9 ± 1.3 vs 2.0 ± 0.4 mm, P < .001) compared with the continuous-loop tape fixation group. There was a significantly higher linear-region stiffness with continuous-loop tape fixation compared with tied-suture fixation (98.8 ± 12.7 vs 85.5 ± 7.5 N/mm, P = .022). No significant difference in ultimate load between groups (517.1 ± 149.2 vs 465.6 ± 64.6 N) was found. The mode of failure was tendon pull-through for the continuous-loop tape group and suture breakage in the tied-suture group ( P < .001). Conclusion: Continuous-loop tape fixation is superior to tied-suture fixation in regard to elongation and stiffness for all–soft tissue quadriceps tendon grafts, but there was no significant difference in ultimate load. Clinical Relevance: Continuous-loop tape fixation of all–soft tissue quadriceps tendon grafts for ACLR is a valid technique with superior tensile properties.