Fresh-Frozen Allograft Anterior Cruciate Ligament Reconstruction

Diagnosis and treatment of anterior cruciate ligament injuries: Consensus of Chinese experts part II: Graft selection and clinical outcome evaluation

Background

In the recent decade, there has been substantial progress in the technologies and philosophies associated with diagnosing and treating anterior cruciate ligament (ACL) injuries in China. The therapeutic efficacy of ACL reconstruction in re-establishing the stability of the knee joint has garnered widespread acknowledgment. However, the path toward standardizing diagnostic and treatment protocols remains to be further developed and refined.

Objective

In this context, the Chinese Association of Orthopaedic Surgeons (CAOS) and the Chinese Society of Sports Medicine (CSSM) collaboratively developed an expert consensus on diagnosing and treating ACL injury, aiming to enhance medical quality through refining professional standards.

Methods

The consensus drafting team invited experts across the Greater China region, including the mainland, Hong Kong, Macau, and Taiwan, to formulate and review the consensus using a modified Delphi method as a standardization approach. As members of the CSSM Lower Limb Study Group and the CAOS Arthroscopy and Sports Medicine Study Group, invited experts concentrated on two pivotal issues: "Graft Selection" and "Clinical Outcome Evaluation" during the second part of the consensus development.

Results

This focused discussion ultimately led to a strong consensus on nine specific consensus terms.

Conclusion

The consensus clearly states that ACL reconstruction has no definitive "gold standard" graft choice. Autografts have advantages in healing capability but are limited in availability and have potential donor site morbidities; allografts reduce surgical trauma but incur additional costs, and there are concerns about slow healing, quality control issues, and a higher failure rate in young athletes; synthetic ligaments allow for early rehabilitation and fast return to sport, but the surgery is technically demanding and incurs additional costs. When choosing a graft, one should comprehensively consider the graft's characteristics, the doctor's technical ability, and the patient's needs. When evaluating clinical outcomes, it is essential to ensure an adequate sample size and follow-up rate, and the research should include patient subjective scoring, joint function and stability, complications, surgical failure, and the return to sport results. Medium and long-term follow-ups should not overlook the assessment of knee osteoarthritis.

Challenges and opportunities in vascularized composite allotransplantation of joints: a systematic literature review

Background

Joint allotransplantation (JA) within the field of vascularized composite allotransplantation (VCA) holds great potential for functional and non-prosthetic reconstruction of severely damaged joints. However, clinical use of JA remains limited due to the immune rejection associated with all forms of allotransplantation. In this study, we aim to provide a comprehensive overview of the current state of JA through a systematic review of clinical, animal, and immunological studies on this topic.

Methods

We conducted a systematic literature review in accordance with the PRISMA guidelines to identify relevant articles in PubMed, Cochrane Library, and Web of Science databases. The results were analyzed, and potential future prospects were discussed in detail.

Results

Our review included 14 articles describing relevant developments in JA. Currently, most JA-related research is being performed in small animal models, demonstrating graft survival and functional restoration with short-term immunosuppression. In human patients, only six knee allotransplantations have been performed to date, with all grafts ultimately failing and a maximum graft survival of 56 months.

Conclusion

Research on joint allotransplantation has been limited over the last 20 years due to the rarity of clinical applications, the complex nature of surgical procedures, and uncertain outcomes stemming from immune rejection. However, the key to overcoming these challenges lies in extending graft survival and minimizing immunosuppressive side effects. With the emergence of new immunosuppressive strategies, the feasibility and clinical potential of vascularized joint allotransplantation warrants further investigation.

Our Preferred Technique for Bone-Patellar Tendon-Bone Allograft Preparation

Anterior cruciate ligament (ACL) reconstruction is an increasingly common procedure as orthopaedic patients seek to remain active longer in life, resulting in more ligamentous knee injuries. Graft selection is at the forefront of decision making in knee reconstruction, with advantages and disadvantages to various grafts, including allograft to autograft. Although the gold standard for the ACL reconstruction of elite athletes and highly active patients has traditionally been bone-patellar tendon-bone autograft (BTB), this graft is not without its disadvantages, such as increased operative time, increased postoperative pain, potential for anterior knee pain, larger incision, violation of the extensor mechanism, and potentially kneeling pain. Soft tissue autografts (hamstring, quadriceps) offer a good alternative; however, they may be associated with higher rerupture rates, as well as associated donor site morbidity. Additionally, soft tissue allografts have a higher graft rupture rate. For this reason, it is the senior author's preference to perform allograft ACL reconstruction with BTB allograft in appropriately selected patients. We describe our technique for an efficient and reproducible BTB allograft preparation.

Diffusion Tensor Imaging for Quantitative Assessment of Anterior Cruciate Ligament Injury Grades and Graft

BACKGROUND

As the need for quantitative assessment of anterior cruciate ligament (ACL) injuries and ACL graft increases, diffusion tensor imaging (DTI) becomes a more valuable measuring tool. However, DTI changes in differing injury grades of ACL and longitudinal graft remain unclear.

PURPOSE

To investigate the diagnostic performance of DTI in quantitatively assessing ACL injury severity and the development of ACL grafts within 6 months of surgery.

STUDY TYPE

A cohort study.

SUBJECTS

Thirty-five patients diagnosed with grades I-IV ACL injuries and 20 volunteers as controls were recruited.

FIELD STRENGTH/SEQUENCE

T₁ -weighted, T₂ -weighted, proton density (PD)-weighted, and DTI at 3.0T MRI.

ASSESSMENT

ACL injury grades in arthroscopic images and DTI quantitative data were evaluated from July 2016 to July 2018.

STATISTICAL TESTS

Chi-square test, analysis of variance, Spearman correlation analysis, and receiver operator characteristic (ROC) curves.

RESULTS

Both fractional anisotropy (FA) (r = -0.898, P < 0.05) and apparent diffusion coefficient (ADC) (r = 0.851, P < 0.05) were significantly correlated with the severity of ACL injuries. The area under the curve (AUC) values for differentiation between low- and high-grade ACL injuries with FA and ADC were 0.973 and 0.963, respectively. Although there were no significant differences in FA (P > 0.05) and ADC (P > 0.05) between grades I and II ACL injuries or in ADC (P > 0.05) between grades III and IV, there were significant differences in FA and ADC between two grades (P < 0.05). There were significant differences in FA (P < 0.05) and ADC (P < 0.05) between normal ACL and 3-month graft postoperation, as well as in ADC values between 3-month and 6-month graft postoperation (P < 0.05).

DATA CONCLUSION

DTI could be used to quantitatively evaluate the ACL injury grades and the development of ACL grafts. The diagnostic efficiency of FA values was higher than that of ADC values.

LEVEL OF EVIDENCE

1 TECHNICAL EFFICACY: Stage 3.

Utility of an allograft tendon for scoliosis correction via the costo-transverse foreman

Current convex tethering techniques for treatment of scoliosis have centered on anterior convex staples or polypropylene tethers. We hypothesized that an allograft tendon tether inserted via the costo-transverse foramen would correct an established spinal deformity. In the pilot study, six 8-week-old pigs underwent allograft tendon tethering via the costo-transverse foreman or sham to test the strength of the transplanted tendon to retard spine growth. After 4 months, spinal deformity in three planes was induced in all animals with allograft tendons. In the treatment study, the allograft tendon tether was used to treat established scoliosis in 11 8-week-old pigs (spinal deformity > 50°). Once the deformity was observed (4 months) animals were assigned to either no treatment group or allograft tendon tether group and progression assessed by monthly radiographs. At final follow-up, coronal Cobb angle and maximum vertebral axial rotation of the treatment group was significantly smaller than the non-treatment group, whereas sagittal kyphosis of the treatment group was significantly larger than the non-treatment group. In sum, a significant correction was achieved using a unilateral allograft tendon spinal tether, suggesting that an allograft tendon tethering approach may represent a novel fusion-less procedure to correct idiopathic scoliosis. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 35:183-192, 2017.

Comparison between two different platelet-rich plasma preparations and control applied during anterior cruciate ligament reconstruction. Is there any evidence to support their use?

INTRODUCTION

To compare the clinical, analytical and graft maturation effects of two different platelet-rich plasma (PRP) preparations applied during anterior cruciate ligament (ACL) reconstruction.

MATERIALS AND METHODS

A total of 150 patients with ACL disruption were included in the study. Arthroscopic ACL reconstruction with patellar tendon allograft was conducted on all knees using the same protocol. One hundred patients were prospectively randomised to either a group to receive double-spinning platelet-enriched gel (PRP) with leukocytes (n=50) or to a non-gel group (n=50). Finally, we included 50 patients treated with a platelet-rich preparation from a single-spinning procedure (PRGF Endoret(®) Technology) without leukocytes. Inflammatory parameters, including C-reactive protein (CRP) and knee perimeters (PER), were measured 24 hours and 10 days after surgery. Postoperative pain score (visual analogue score [VAS]) was recorded the day after surgery. Follow-up visits occurred postoperatively at 3, 6, and 12 months. The International Knee Documentation Committee scale (IKDC) was included to compare functional state, and MRI was conducted 6 months after surgery.

RESULTS

The PRGF group showed a statistically significant improvement in swelling and inflammatory parameters compared with the other two groups at 24 hours after surgery (p<0.05). The results did not show any significant differences between groups for MRI and clinical scores.

CONCLUSIONS

PRGF used in ACL allograft reconstruction was associated with reduced swelling; however, the intensity and uniformity of the graft on MRI were similar in the three groups, and there was no clinical or pain improvement compared with the control group.

LEVEL OF EVIDENCE

II.

Over-the-top double-bundle revision ACL reconstruction

Revision ACL presents many technical issues that are not seen in the primary ACL reconstruction. A variety of surgical techniques for revising ACL reconstruction have been described in the literature to address these concerns. The purpose of this article is to present a novel technique consisting in a non-anatomic double-bundle ACL revision reconstruction, using a fresh-frozen Achilles tendon allograft with soft tissue fixation. This technique is a valid treatment option when faced with a complex scenario such as ACL revision surgery.

Allograft anterior cruciate ligament reconstruction in the young, active patient: Tegner activity level and failure rate

PURPOSE

The purpose was to analyze outcomes of nonirradiated, fresh-frozen bone-patellar tendon-bone (BPTB) allograft anterior cruciate ligament (ACL) reconstruction in patients aged under 40 years with regard to activity level (Tegner score).

METHODS

Between 1993 and 2005, 111 patients, aged under 40 years, underwent primary, nonirradiated, fresh-frozen BPTB allograft ACL reconstruction and were retrospectively reviewed. Follow-up was limited to a minimum of 24 months. Patients with concomitant ligament injuries and previous surgeries were excluded. Seventy-eight patients met the inclusion criterion and were available for follow-up. Four hundred eleven patients had BPTB autograft ACL reconstructions and comprised the control group. Failure of the graft was defined as repeat ACL reconstruction because of reinjury or graft failure, 2+ Lachman (no endpoint), any pivot shift, and/or 5-mm side-to-side KT-1000 difference (MEDmetric, San Diego, CA) or greater. Initial examinations, surgical findings, and follow-up examinations were prospectively entered into a computerized relational database. The results were assessed by both objective and subjective measures.

RESULTS

High-activity allograft patients had a 2.6- to 4.2-fold increase in the probability of graft failure compared with low-activity BPTB allograft patients and low- and high-activity BPTB autograft patients. Patients undergoing BPTB autograft reconstruction reported significantly fewer problems on a visual analog scale and scored significantly higher on the postoperative Tegner activity scale than patients undergoing allograft reconstruction.

CONCLUSIONS

The active allograft group is 2.6 to 4.2 times more likely to fail compared with low-activity allografts and low- and high-activity autografts. We conclude that fresh-frozen BPTB allografts should not be used in young patients who have a high Tegner activity score because of their higher risk of failure.

LEVEL OF EVIDENCE

Level III, retrospective comparative study.

Two to five year results of primary ACL reconstruction using doubled tibialis anterior allograft

The aim of the study was to report the 2-5 year results of primary ACL reconstruction with doubled tibialis anterior allograft. Seventy-three patients who underwent primary ACL reconstruction with doubled tibialis anterior allografts with minimum 2 year follow-up were included in the study. Sixty-four patients were available for follow-up. The median age was 27 years (16-55). There were 33 men and 31 women. The median follow-up was 44.5 months (24-55 months). There were two complications, 1 DVT with subsequent PE, and 1 hardware problem. Four patients had failure of their graft, and six patients required repeat arthroscopy. The median Lysholm score was 88 (range 70-95), and the median Tegner activity score was 6.5 (range 3-10). The median IDKC was 92 (range 73-100). According to the IDKC score, 60% of patients were rated as excellent, 27% as good, and 13% as fair. A total of 25 were able to attend the clinical assessment. On KT-1000, 15 (60%) patients had less than 3 mm side-side difference. Eighteen patients (72%) had no pivot shift. ACL reconstruction with allograft tibialis anterior tendon provided good functional results with a low-failure rate at 2-5 years. There was a statistically significant difference in outcome between men and women, with men performing better on the Lysholm and the IDKC scales.

Has platelet-rich plasma any role in anterior cruciate ligament allograft healing?

PURPOSE

The aim of this study was to evaluate and compare the clinical and inflammatory parameters with the addition of platelet-derived growth factor (PDGF) in primary anterior cruciate ligament (ACL) reconstruction with bone-patellar tendon-bone allograft.

METHODS

We prospectively randomized 100 patients undergoing arthroscopic patellar tendon allograft ACL reconstruction to a group in whom platelet-enriched gel was used (n = 50) and a non-gel group (n = 50). The platelet concentration was 837 x 10(3)/mm(3), and the gel was introduced inside the graft and the tibial tunnel. Demographic data were comparable between groups. The mean follow-up was 24 months for both groups and included a history, clinical evaluation with the International Knee Documentation Committee score, radiographs, and magnetic resonance imaging.

RESULTS

There were no differences in the number of associated injuries. The results did not show any statistically significant differences between the groups for inflammatory parameters (perimeters of the knee and C-reactive protein level), magnetic resonance imaging appearance of the graft, and clinical evaluation scores (visual analog scale, International Knee Documentation Committee, and KT-1000 arthrometer [MEDmetric, San Diego, CA]).

CONCLUSIONS

At this time, the therapeutic role of PDGF in ACL reconstruction remains unclear. The use of PDGF, on the graft and inside the tibial tunnel, in patients treated with bone-patellar tendon-bone allografts has no discernable clinical or biomechanical effect at 2 years' follow-up. More clinical studies will be needed to show the efficacy and use of these factors in daily practice in ACL reconstruction.

LEVEL OF EVIDENCE

Level I, prospective, randomized, double-blind study.

Is there significant variation in the material properties of four different allografts implanted for ACL reconstruction

The aims of our study were to: (1) determine if there are differences in the material properties of tendon obtained from implanted tibialis anterior, achilles, bone-patella- bone and tibialis posterior allografts; (2) determine the variability in material properties between the implanted specimens. A total of 60 specimens were collected from fresh frozen allografts implanted at ACL reconstruction. Specimens collected included 15 tibialis anterior, 15 tibialis posterior, 15 achilles and 15 bone-patella-bone tendons. Each specimen was mounted in a custom made cryogrip. The mounted specimens were loaded onto a MTS Testline servo-hydraulic testing machine in a uni-axial tensile test configuration. Specimens were subjected to a strain rate of 5% per second until the ultimate tensile stress (UTS), failure strain and high strain modulus was calculated for each specimen after being normalized for specimen dimensions. Individual material properties were tested using one way analysis of variance (ANOVA) and post hoc Tukey's B test with a P value of <0.05 considered significant. Homogeneity of variance was assessed using the Levene's test. As a result, no significant difference was found between all four grafts with regards to UTS, failure strain or high strain linear modulus. The UTS was plotted against the modulus demonstrating a linear relationship which is typical of soft tissues. Significant variability in the results were observed. In conclusion, there was no significant statistical difference between the material properties of the four tendon allografts tested. But significant variability in results was observed within groups and between groups, which may provide one explanation for the range of results in allograft ACL reconstruction reported in the literature.