Outcomes After 1-Stage Versus 2-Stage Revision Anterior Cruciate Ligament Reconstruction

Revision Anterior Cruciate Ligament Reconstruction and Associated Procedures

Failure of anterior cruciate ligament reconstruction (ACLR) is a common yet devastating complication due to inferior clinical outcomes associated with revision ACLR. Identifying the cause and associated risk factors for failure is the most important consideration during preoperative planning. Special attention to tunnel quality, concomitant injuries, and modifiable risk factors will help determine the optimal approach and staging for revision ACLR. Additional procedures including lateral extra-articular tenodesis and osteotomy may be considered for at-risk populations. The purpose of this review is to explore causes of ACLR failure, clinical indications and appropriate patient evaluation, and technical considerations when performing revision ACLR.

Single- or two-stage revision after failed ACL reconstruction: No differences in re-revision rates and clinical outcomes

PURPOSE

The surgeons' choice of a single-stage or a two-stage procedure in revision anterior cruciate ligament reconstruction (ACLr) is based on the possibility of reuse of the tibia and femoral bone tunnels after primary ACLr. The purpose of this study was to compare failure rates and clinical outcomes following single-stage and two-stage ACL revisions in a cohort of patients from The Danish Knee Ligament Reconstruction Registry.

METHODS

Patients identified from 2005 to 2022 with ACL revision and met the following criteria: minimum 2-year follow-up, isolated ACL revision and registered single- or two-stage ACL revision. The primary outcome was ACL re-revision rate. Secondary outcomes were arthrometer sagittal knee laxity (side-to-side difference) and pivot shift (rotational stability difference) evaluated at 1-year follow up.

RESULTS

One thousand five hundred seventy-four ACL revisions were included in the study (1331 = single-stage and 243 = two stage). Baseline characteristics showed no difference in relation to age, gender, knee laxity, pivot shift, meniscus injury, cartilage damage or injury mechanism between the two groups. Significant differences were found in relation to the type of graft. No statistical difference in 2-years revision rates between single-stage group 2.79 (95% CI 2.03-3.84) and two-stage group 2.93 (95% CI 1.41-6.05) was found. No significant difference was seen in knee laxity and pivot shift between stage-groups at 1-year follow up. Both groups demonstrated significant improvements in knee stability from baseline to 1-year follow-up.

CONCLUSION

The present study found that ACL revision outcomes were similar in terms of rerevision rates and knee laxity for patients managed with a single- or a two-stage surgical strategy.

LEVEL OF EVIDENCE

Level III.

Revision Anterior Cruciate Ligament Reconstruction in Skeletally Immature Patients

Revision anterior cruciate ligament (ACL) reconstruction in the skeletally immature patient is a challenging procedure for pediatric patients with recurrent instability after primary ACL reconstruction. The pediatric population presents unique technical challenges and complications secondary to open physes compared with the adult population. Complications can include growth disturbances, recurrent graft failure, instability, and secondary chondral and/or meniscal injury. Moreover, identifying the etiology of graft failure is critical for a successful revision. Patients should undergo a complete history and physical examination with a focus on patient physiologic age, physeal status, mechanical axis, tibial slope, collagen status, injury mechanism, concomitant injuries, and previous surgical procedures. The surgeon must be adept at reconstruction with various grafts as well as socket or tunnel preparation and fixation, including over-the-top, all-epiphyseal, transphyseal, extra-articular augmentation, and staging approaches. Reported rates of return to sport are lower than those of primary reconstruction, with higher rates of cartilage and meniscal degeneration. Future research should focus on optimizing surgical outcomes and graft survivorship after primary ACL reconstruction with minimized trauma to the physis.

Management of Bone Loss and Tunnel Widening in Revision ACL Reconstruction

➤ Both mechanical and biological factors can contribute to bone loss and tunnel widening following primary anterior cruciate ligament (ACL) reconstruction.➤ Revision ACL surgery success is dependent on graft position, fixation, and biological incorporation.➤ Both 1-stage and 2-stage revision ACL reconstructions can be successful in correctly indicated patients.➤ Potential future solutions may involve the incorporation of biological agents to enhance revision ACL surgery, including the use of bone marrow aspirate concentrate, platelet-rich plasma, and bone morphogenetic protein-2.

Consistent Indications and Good Outcomes Despite High Variability in Techniques for Two-Stage Revision Anterior Cruciate Ligament Reconstruction: A Systematic Review

PURPOSE

To systematically review the current literature regarding the indications, techniques, and outcomes after 2-stage revision anterior cruciate ligament reconstruction (ACLR).

METHODS

A literature search was performed using SCOPUS, PubMed, Medline, and the Cochrane Central Register for Controlled Trials according to the 2020 Preferred Reporting Items for Systematic Reviews and Meta Analyses statement. Inclusion criteria was limited to Level I-IV human studies reporting on indications, surgical techniques, imaging, and/or clinical outcomes of 2-stage revision ACLR.

RESULTS

Thirteen studies with 355 patients treated with 2-stage revision ACLR were identified. The most commonly reported indications were tunnel malposition and tunnel widening, with knee instability being the most common symptomatic indication. Tunnel diameter threshold for 2-stage reconstruction ranged from 10 to 14 mm. The most common grafts used for primary ACLR were bone-patellar tendon-bone (BPTB) autograft, hamstring graft, and LARS (polyethylene terephthalate) synthetic graft. The time elapsed from primary ACLR to the first stage surgery ranged from 1.7 years to 9.7 years, whereas the time elapsed between the first and second stage ranged from 21 weeks to 13.6 months. Six different bone grafting options were reported, with the most common being iliac crest autograft, allograft bone dowels, and allograft bone chips. During definitive reconstruction, hamstring autograft and BPTB autograft were the most commonly used grafts. Studies reporting patient-reported outcome measures showed improvement from preoperative to postoperative levels in Lysholm, Tegner, and objective International Knee and Documentation Committee scores.

CONCLUSIONS

Tunnel malpositioning and widening remain the most common indications for 2-stage revision ACLR. Bone grafting is commonly reported using iliac crest autograft and allograft bone chips and dowels, whereas hamstring autograft and BPTB autograft were the most used grafts during the second-stage definitive reconstruction. Studies showed improvements from preoperative to postoperative levels in commonly used patient reported outcomes measures.

LEVEL OF EVIDENCE

Level IV, systematic review of Level I, III, and IV studies.

Revision anterior cruciate ligament reconstruction

Anterior cruciate ligament (ACL) graft failure from rupture, attenuation, or malposition may cause recurrent subjective instability and objective laxity, and occurs in 3% to 22% of ACL reconstruction (ACLr) procedures. Revision ACLr is often indicated to restore knee stability, improve knee function, and facilitate return to cutting and pivoting activities. Prior to reconstruction, a thorough clinical and diagnostic evaluation is required to identify factors that may have predisposed an individual to recurrent ACL injury, appreciate concurrent intra-articular pathology, and select the optimal graft for revision reconstruction. Single-stage revision can be successful, although a staged approach may be used when optimal tunnel placement is not possible due to the position and/or widening of previous tunnels. Revision ACLr often involves concomitant procedures such as meniscal/chondral treatment, lateral extra-articular augmentation, and/or osteotomy. Although revision ACLr reliably restores knee stability and function, clinical outcomes and reoperation rates are worse than for primary ACLr.

Comparison of the Clinical Outcomes of Revision and Primary ACL Reconstruction: A Matched-Pair Analysis With 3-5 Years of Follow-up

BACKGROUND

There are limited studies designed by matching related factors to compare clinical outcomes and return to sport (RTS) between patients undergoing revision anterior cruciate ligament reconstruction (R-ACLR) and primary ACLR (P-ACLR).

PURPOSE

(1) To compare the outcomes between R-ACLR and P-ACLR in a matched-pair analysis with 3- to 5-year follow-up and (2) to evaluate patient-reported factors for not returning to preinjury-level sport.

STUDY DESIGN

Cohort study; Level of evidence, 4.

METHODS

Patients who underwent R-ACLR between September 2016 and November 2018 were propensity matched by age, sex, body mass index, passive anterior tibial subluxation, and generalized hypermobility in a 1:1 ratio to patients who underwent P-ACLR during the same period. By combining in person follow-up at 2 years postoperatively and telemedicine interview at the final follow-up (January 2022), knee stability and clinical scores were compared, including International Knee Documentation Committee (IKDC), Lysholm, and Tegner. Status of RTS was requested, specifically whether the patient returned to preinjury level of sport. Patient-reported reasons for not returning were analyzed.

RESULTS

There were 63 matched pairs in the present study. Knee stability was similar in terms of KT-2000 arthrometer, Lachman test, and pivot-shift test results between the groups at 2 years of follow-up. At the final follow-up, no significant difference was found between groups for postoperative clinical scores (IKDC, Tegner, and Lysholm) (P > .05). There was a significant difference in total RTS: 53 (84.1%) in the P-ACLR cohort and 41 (65.1%) in the R-ACLR cohort (P = .014). No significant difference was shown in terms of RTS at the same level: 35 (55.6%) in P-ACLR and 31 (49.2%) in R-ACLR (P = .476). Significantly more patients showed fear of reinjury: 26 of 32 (81.3%) in the R-ACLR group as compared with 15 of 28 (53.5%) in the P-ACLR group (P < .021).

CONCLUSION

R-ACLR resulted in similar clinical scores (IKDC, Tegner, and Lysholm) but significantly lower RTS versus P-ACLR at 3 to 5 years of follow-up. Fear of reinjury was the most common factor that caused sport changes in patients with R-ACLR.

Bone Marrow Aspirate Concentrate With Two-Staged-Revision ACL Reconstruction

Background:

The incidence of anterior cruciate ligament (ACL) injuries, reconstructions, and re-ruptures has rapidly increased. Patients with failed ACL reconstructions have been reported to suffer from far worse outcomes as compared with those with primary reconstructions, prompting the advancement of surgical and biologic techniques. Effective treatment of re-tears has been shown to be achieved either utilizing a 1-stage or 2-staged approach, with the latter preferred if the patient presents with significant bone loss, previously malpositioned tunnels, or unacceptable tunnel expansion. Recent literature has shown the efficacy of bone marrow aspirate concentrate (BMAC) in improving clinical outcomes and graft integration as well as accelerated ligamentization.

Indication:

Patients are indicated for surgery when presenting with chronic ACL graft failure and objective insufficiency as well as concerns regarding tunnel overlap, enlargement, or interference. Contraindications for revision involve influences of concurrent injuries that may be secondary causes of the ACL injury.

Technique Description:

After bone marrow aspiration is performed, the tibial and femoral tunnel apertures are debrided of fibrous tissue with a combination of a shaver and curettes. A threaded guide wire is passed and the interference screws are removed, revealing the residual ruptured graft. A shaver and radiofrequency ablation device are utilized to clean off remaining graft remnants. Sequential debridement and reaming are performed to remove any residual fibrous tissue or sclerotic bone from the tunnel. The demineralized bone matrix is then combined with the prepared BMAC in a syringe with a cannula extension and subsequently injected into the tunnels. A freer elevate is used to tamp and smooth the graft to match the surrounding contour. A 12-mm cannulated allograft bone dowel is then passed up into the tibial tunnel and gently tamped into place.

Results:

Within 2 years postoperatively, patients are expected to have improved overall knee-specific quality of life, reduced pain, and a successful return to activities. No differences in outcomes have been noted in the literature between 1-staged and 2-staged ACL reconstructions.

Discussion/Conclusion:

Recent advancements in our understanding of the effects of BMAC in the setting of an ACL reconstruction should prompt surgeons to consider such treatments in indicated patients.

Patient Consent Disclosure Statement:

The author(s) attests that consent has been obtained from any patient(s) appearing in this publication. If the individual may be identifiable, the author(s) has included a statement of release or other written form of approval from the patient(s) with this submission for publication.

Tunnel Management in Revision Anterior Cruciate Ligament Reconstruction: Current Concepts

Bone tunnel-related complications are frequently encountered during revision anterior cruciate ligament reconstruction (ACLR). Issues with tunnel positioning, enlargement, containment, and hardware interference may complicate surgery and compromise outcomes. As a result, several strategies have emerged to address these issues and optimize results. However, a systematic, unified approach to tunnel pathology in revision ACLR is lacking. The purpose of this review is to highlight the current state of the literature on bone tunnel complications and, although extensive literature on the subject is lacking, present an updated approach to the evaluation and management of tunnel-related issues in revision ACLR.

Multiple revision anterior cruciate ligament reconstruction: not the best but still good

PURPOSE

Given the paucity of literature on the re-revision of ACL, the current study was undertaken. The purpose of this systematic review was to synthesise and qualitatively assess the currently available evidence in the literature regarding the re-revision of ACL reconstruction (rrACLR).

METHODS

A systematic review was conducted based on the PRISMA guidelines. The following search terms were used in the title, abstract and keywords fields: "ACL" or "anterior cruciate ligament" AND "revision" or "multiple" or "repeat". The outcome data extracted from the studies were the Lysholm score, Subjective IKDC, Marx Score, Tegner, Marx Score, KOOS score, radiological changes and the rate of return to sports. Complications, failures and/or revision surgery were also analysed.

RESULTS

The cohort consisted of 295 patients [191 (64.7%) men and 104 (35.3%) women] with a mean age of 29.9 ± 2.8 years (range 14-58 years) from 10 studies. The mean postoperative follow-up (reported in all studies except one) was 66.9 ± 44.7 months (range 13-230.4 months). Associated injuries were 103 (34.9%) medial meniscus tears, 57 (19.3%) lateral meniscus tears, 14 (4.7%) combined medial plus lateral meniscus tears, 11 (3.7%) meniscal tears (not specified), 252 (85.4%) cartilage lesions, 6 (2.0%) medial collateral ligament injury and 2 (0.7%) lateral collateral ligament injuries. In 47 (15.9%) patients an extra-articular plasty was performed for the anterolateral ligament. In all studies that reported pre- and post-operative IKDC (subjective and objective) and Lysholm score, there was a significant improvement compared to the pre-operative value (p < 0.05). At the final follow-up, laxity measured with KT-1000 was found to be 2.2 ± 0.6 mm. 31 (10.5%) out of 295 patients returned to their pre-injury activity level. A total of 19 (6.4%) re-ruptures were found, while only 4 (1.4%) complications (all minors) were reported, out of which 2 (0.7%) were superficial infections, 1 (0.3%) cyclops lesion and 1 (0.3%) flexion loss.

CONCLUSION

Multiple revisions of anterior cruciate ligament reconstruction allow acceptable clinical results and a good degree of knee stability with a low rate of subsequent new re-ruptures but the possibility of regaining pre-injury sports activity is poor; whenever possible, it is preferred to revise the ligament in one stage. This surgery remains a challenge for orthopaedic surgeons and many doubts persist regarding the ideal grafts, additional extra-articular procedures and techniques to use.

LEVEL OF EVIDENCE

IV.

STUDY REGISTRATION

PROSPERO-CRD42022352164 ( https://www.crd.york.ac.uk/prospero/ ).

Massive foreign body reaction and osteolysis following primary anterior cruciate ligament reconstruction with the ligament augmentation and reconstruction system (LARS): a case report with histopathological and physicochemical analysis

BACKGROUND

Autologous hamstrings and patellar tendon have historically been considered the gold standard grafts for anterior cruciate ligament reconstruction (ACLR). In the last decades, the utilization of synthetic grafts has re-emerged due to advantageous lack of donor site morbidity and more rapid return to sport. The Ligament Augmentation and Reconstruction System (LARS) has demonstrated to be a valid and safe option for ACLR in the short term. However, recent studies have pointed out the notable frequency of associated complications, including synovitis, mechanical failure, and even chondrolysis requiring joint replacement.

CASE PRESENTATION

We report the case of a 23-year-old male who developed a serious foreign body reaction with wide osteolysis of both femoral and tibial tunnels following ACLR with LARS. During first-stage arthroscopy, we performed a debridement of the pseudocystic mass incorporating the anterior cruciate ligament (ACL) and extending towards the tunnels, which were filled with autologous anterior iliac crest bone graft chips. Histological analysis revealed the presence of chronic inflammation, fibrosis, and foreign body giant cells with synthetic fiber inclusions. Furthermore, physicochemical analysis showed signs of fiber depolymerization, increased crystallinity and formation of lipid peroxidation-derived aldehydes, which indicate mechanical aging and instability of the graft. After 8 months, revision surgery was performed and ACL revision surgery with autologous hamstrings was successfully carried out.

CONCLUSIONS

The use of the LARS grafts for ACLR should be cautiously contemplated considering the high risk of complications and early failure.

Arthroscopic Bone Graft Technique for Two-Stage Revision Anterior Cruciate Ligament Reconstruction

Revision anterior cruciate ligament reconstruction is an increasingly common procedure, with 2-stage surgery often required to address large bone defects and malpositioned tunnels. The arthroscopic bone grafting technique described herein uses morselized allograft bone to provide reproducible fill of asymmetrical bone defects without autograft harvest or additional loss of native bone. The second stage of the anterior cruciate ligament reconstruction can typically proceed 6 months following bone grafting.

BIOMECHANICAL EVALUATION OF AN INVERTED FIXATION FOR ACL RECONSTRUCTION WITH NONMETALLIC HARDWARE AND TIBIAL SUBCORTICAL SUPPORT TO INCREASE STRENGTH AT THE TIBIAL SITE

In this paper, we evaluate the initial biomechanical properties of an anterior cruciate ligament (ACL) reconstruction technique that inverts the anatomical location of the commonly used hardware and relies the tibial fixation on the subcortical bone to increase tibial site strength. Four 7-specimen groups were tested in a porcine model: for the control ACL reconstruction technique, the femur with a cross-pin fixation supported in the trabecular bone and the tibia with a biodegradable interference screw (BIS); for the new proposed technique, the femur with a BIS and the tibia with a cross-pin fixation leaned on the tibial subcortical bone. The specimens were subjected to cyclic and load-to-failure tests to compute their biomechanical performance. At the tibia, the cross-pin fixation revealed higher resistance than the BIS ([Formula: see text] for ultimate load and [Formula: see text] = 0.006 for yield load), additionally cyclic and total displacement at representative loads showed extremely high values with BIS fixation (in two specimens greater than 9[Formula: see text]mm for 250 N and greater than 10[Formula: see text]mm for 450[Formula: see text]N). At the femur, no differences between fixations were observed. The inverted ACL reconstruction improves resistance at the tibial site with respect to the control technique, with similar resistance at the femoral site and no differences in total displacement at representative loads. It offers a useful and robust solution when greater tibial resistance is required.

Bone Grafting Technique in Revision ACL Reconstruction: Coring Reamer and Dowel Trick

One- or two-staged bone grafting is sometimes required for tunnel malposition and/or tunnel widening in revision anterior cruciate ligament (ACL) reconstruction. The aim of this procedure is to restore the correct position of the ACL graft in the revision setting to provide a stable and functional ACL, thereby reproducing normal knee kinematics. We present a technique that allows for a cost-effective, convenient tunnel grafting of a femoral head allograft bone dowel into both femoral and tibial defects in revision ACL reconstruction.

Combined Revision Anterior Cruciate Ligament and Anterolateral Ligament Reconstruction

There has been a substantial increase in the number of revision anterior cruciate ligament (ACL) reconstructions performed in the past decade. This Technical Note describes combined revision ACL and anterolateral ligament reconstruction using outside-in drilling, which avoids the need for 2-stage revision ACL reconstruction because it allows unconstrained anatomic placement.

Prevalence and Incidence of Chondral and Meniscal Lesions in Patients Undergoing Primary and Subsequent Revision Anterior Cruciate Ligament Reconstruction: An Analysis of 213 Patients From the SANTI Group

BACKGROUND

Previous studies have shown a higher prevalence of meniscal and chondral lesions at the time of revision anterior cruciate ligament reconstruction (R-ACLR) compared with primary ACLR procedures. However, studies that follow the development of meniscal and chondral status through primary and subsequent R-ACLR are scarce.

PURPOSE

To compare the prevalence of meniscal and chondral injuries in patients undergoing primary ACLR and subsequent R-ACLR.

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

Patients who underwent ACLR and subsequently needed R-ACLR between January 2009 and February 2018 in a single center were included. A retrospective analysis of prospectively collected data was conducted.

RESULTS

A total of 213 patients were included, with a mean follow-up of 59.7 months. The mean age was 22 years at primary ACLR and 26.1 years at the time of revision. The proportion of meniscal tears was higher at the time of R-ACLR compared with the time of primary reconstruction (70.0% vs 44.6%, respectively; P < .001). Similarly, the prevalence of chondral lesions was significantly higher at the time of revision versus the primary reconstruction (15.5% vs 7.0%, respectively; P = .003).

CONCLUSION

R-ACLR is associated with a higher rate of concomitant meniscal and chondral lesions than primary ACLR.

Psychological, physical and social factors influence decision to return to sport after revision ACL reconstruction with BPTB graft

PURPOSE

There is limited evidence in literature regarding the patient-reported factors that influence their return to sport (RTS) in revision anterior cruciate ligament reconstruction (ACLR). The medium-term results of a prospective consecutive cohort of patients undergoing single- and two-stage revision ACLR with bone patellar tendon bone graft (BPTB) and patient-reported factors that influence their decision to return to sport are presented in this study.

METHODS

Seventy-two patients were included in this prospective study. Single- or two-stage revision with BPTB graft was performed based on pre-operative planning. Iliac crest bone graft was used. Pre-operative and follow-up Lysholm and Tegner activity scores and RTS, level of sport and patient-reported factors affecting RTS were recorded. The mean follow-up was 9 years (SD 2.7 years).

RESULTS

Single-stage revision ACLR was performed in 61 patients. In 11 patients (15%), revision ACLR was performed in two stages. There was a significant improvement in Lysholm score from mean 51.1 to 86.7 (p < 0.001). The incidence of re-rupture in this cohort was 0%. The median Tegner score was 6 (range 2-9). Twenty-five patients (34.7%) did not return to any sport at final follow-up. Twenty-nine (40.2%) patients returned to their pre-injury level of sport. Fear of reinjury (79%, p < 0.001) and persistent knee symptoms (35.8%, p = 0.03) were the most common factors limiting RTS in non-returners.

CONCLUSION

Psychological and social factors may have an influence on RTS in addition to physical factors.

LEVEL OF EVIDENCE

Level III.

Larger Prior Tibial Tunnel Size Is Associated with Increased Failure Risk following Revision Anterior Cruciate Ligament Reconstruction

We hypothesize that larger prior tunnel size is associated with an increased risk of failure of single-stage revision anterior cruciate ligament reconstruction (ACLR) as defined by the performance of a re-revision (third) ACLR on the index knee. Retrospective review identified 244 patients who underwent single-stage revision ACLR at a single center with available preoperative radiographs. Patient and surgical factors were extracted by chart review. The maximum diameter of the tibial tunnel was measured on lateral radiographs and the maximum diameter of the femoral tunnel was measured on anteroposterior radiographs. Record review and follow-up phone calls were used to identify failure of the revision surgery as defined by re-revision ACLR on the index knee. One hundred and seventy-one patients (70%) were reviewed with a mean of 3.9 years follow-up. Overall, 23 patients (13.4%) underwent re-revision surgery. Mean tibial tunnel size was 12.6 ± 2.8 mm (range: 5.7-26.9 mm) and mean femoral tunnel size was 11.7 ± 2.8 mm (range: 6.0-23.0 mm). Re-revision risk increased with tibial tunnel size. Tibial tunnels 11 mm and under had a re-revision risk of 4.2%, while tunnels > 11 mm had a risk of 17.1% (relative risk: 4.1, p = 0.025). No significant association between femoral tunnel size and re-revision risk was noted. Patients with prior tibial tunnels > 11mm in diameter at revision surgery had significantly increased risk of re-revision ACLR. Further studies are needed to explore the relationship between prior tunnel size and outcomes of revision ACLR.

One-Stage ACL Revision Using a Bone Allograft Plug for a Semianatomic Tibial Tunnel That Is Too Anterior

Revision of an anterior cruciate ligament (ACL) reconstruction can be performed as a one-stage or two-stage surgery. Several factors must be taken into consideration when making this choice, especially the size and position of the existing tunnels. When the tibial tunnel is semianatomic, it is difficult to make a new tunnel in the correct position without overlapping the existing tunnel. For this reason, we have developed a one-stage ACL revision surgery that uses a bone allograft plug. When it comes to choosing a reconstruction technique, we believe that combined intra-articular and extra-articular reconstruction with the iliotibial band is suitable when the hamstring tendons are not available, combined with clinical findings of translational and rotational instability. Because the existing tunnels require reorientation, a new femoral tunnel can be created by outside-in drilling to eliminate the risk of overlap, while an allograft bone plug can be used to fill the overly anterior tibial tunnel and allow us to drill the correct tibial tunnel right away. In our hands, this is a safe and effective technique, but longer follow-up is needed to validate its indications.

Revision Anterior Cruciate Ligament Reconstruction Using Bone-Patellar Tendon-Bone Graft Combined With Modified Lemaire Technique Versus Hamstring Graft Combined With Anterolateral Ligament Reconstruction: A Clinical Comparative Matched Study With a Mean Follow-up of 5 Years From The SANTI Study Group

BACKGROUND

Additional lateral extra-articular tenodesis (LET) has recently been correlated with improved clinical outcomes and reduced failure rates in revision anterior cruciate ligament (ACL) reconstruction (ACLR). However, no data are available on clinical outcomes and reoperation after revision ACLR using different LET procedures.

PURPOSE

To compare the clinical outcomes of ACL + anterolateral ligament (ALL) reconstruction using hamstring tendon graft (HT-ALL) and a bone-patellar tendon-bone (BPTB) graft + modified Lemaire tenodesis procedure (BPTB-Lemaire) in the setting of revision ACLR and to determine whether ALL reconstruction is associated with an increased rate of adverse outcomes when compared with a modified Lemaire tenodesis procedure.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

Descriptive data and clinical outcomes were prospectively collected from patients who underwent revision ACLR with LET between 2009 and 2018 with a minimum follow-up of 2 years. Patients with an HT autograft combined with ALL reconstruction (HT-ALL group) were matched in a 1:1 propensity ratio to patients with a BPTB autograft combined with a modified Lemaire LET procedure (BPTB-Lemaire group). The evaluated parameters included complications and reoperations; knee laxity tests; return to sports; and various scores, including the Lysholm knee score, Tegner activity scale, Anterior Cruciate Ligament Return to Sport After Injury scale, Marx activity rating scale, International Knee Documentation Committee subjective knee evaluation form, and Knee injury and Osteoarthritis Outcome Score.

RESULTS

In total, 36 matched pairs were included in the analysis. The mean follow-up durations for the BPTB-Lemaire and HT-ALL groups were 56 ± 35 and 57 ± 23 months, respectively (P = .91). No significant differences were found in graft rupture rate (HT-ALL, 0%; BPTB-Lemaire, 11.1%; P = .13) or reoperations (HT-ALL, 8.3%; BPTB-Lemaire, 22.2%; P = .23). No specific complications with regard to LET were noted in either group. Additionally, there were no significant differences in knee laxity parameters, return to sports, or clinical scores between the groups at the final follow-up, except for the Tegner activity scale score (HT-ALL, 6.4; BPTB-Lemaire, 7.3; P = .03). HT-ALL was associated with a shorter surgical time (41.4 vs 59.8 minutes; P < .0001).

CONCLUSION

HT-ALL was at least equivalent, in terms of clinical outcomes, to the more commonly performed procedure, BPTB-Lemaire. Performing ALL reconstruction in the setting of revision ACLR is therefore safe and effective.

Two-Stage Revision Anterior Cruciate Ligament Reconstruction with Cannulated Allograft Bone Dowels Soaked in Bone Marrow Aspirate Concentrate

Anterior cruciate ligament reconstruction (ACLR) is one of the most common orthopedic procedures performed each year. The majority of patients undergoing these reconstructions will experience long-term stability and symptomatic relief; however, some will require a revision ACLR procedure. In general, revision ACLRs are more challenging than primary ACLRs due to several diagnostic and technical considerations. A revision ACLR can be performed with either a one-stage or two-stage procedure, which is based on the presence or absence of malpositioned tunnels, bone loss, and tunnel expansion. Recently, the introduction of preshaped allograft bone dowels as a bone grafting option has gained popularity. They provide immediate structural stability and avoid donor site morbidity associated with autografts. The purpose of this article is to outline a bone-grafting tunnel technique with cannulated allograft bone dowels soaked in bone marrow aspirate concentrate (BMAC) used in the first stage of a staged revision ACLR procedure.

Revision Anterior Cruciate Ligament Reconstruction: Tibial Tunnel-First Graft-Sizing Technique

Revision anterior cruciate ligament reconstruction (R-ACLR) has become more common as the number of failed primary ACLRs increase. Although increasingly common, R-ACLR has a greater failure rate than a primary reconstruction. Technical errors, particularly in tunnel placement, account for a large proportion of graft failure in R-ACLR as well as re-revision cases. Tunnel placement and trajectory is particularly important in R-ACLR and becomes more challenging with each additional revision attempt. This is in part because any tunnels created for revision may converge with formerly drilled tunnels or face interference hardware creating, complicating proper graft fixation. While there are many approaches to revision ACL surgery, our technique describes a simple, tibial tunnel-first graft-sizing method initially reaming tunnels with very small diameters and sequentially working your way up to more anatomic diameters.

Allograft Bone Dowels Show Better Incorporation in Femoral Versus Tibial Tunnels in 2-Stage Revision Anterior Cruciate Ligament Reconstruction: A Computed Tomography-Based Analysis

PURPOSE

The purpose of this study was to quantitatively evaluate the radiographic outcomes of allograft dowels used in 2-stage revision anterior cruciate ligament reconstruction (ACLR) and to compare the incorporation rates of dowels placed in tibial and femoral tunnels.

METHODS

Prospective review of patients who underwent 2-stage revision ACLR with allograft bone dowels. Inclusion criteria were tibial/femoral tunnel diameter of ≥14 mm on preoperative computed tomography (CT) or overlapping of prior tunnels with planned tunnels. Second-stage timing was determined based on qualitative dowel integration on CT obtained at ∼3 months after the first stage. Quantitative analysis of incorporation rates was performed with the union ratio (UR) and occupying ratio (OR) on postoperative CT scans.

RESULTS

Twenty-one patients, with a mean (SD) age of 32.1 (11.4; range, 18-50) years, were included. Second-stage procedures were performed at a mean (SD) of 6.5 (2.1; range, 2.4-11.5) months after first-stage revision. All dowels showed no signs of degradation at the host bone/graft junction at the second-stage procedure. The mean (SD) diameter of the dowels placed in tibial tunnels was greater than those placed in femoral tunnels (16.1 [2.3] mm vs 12.4 [1.6] mm; P < .05). CT was obtained at a mean (SD) of 121 (28; range, 59-192) days after the first-stage surgery. There was no difference between the OR of femoral and tibial tunnels (mean [SD], 87.6% [4.8%] vs 85.7% [10.1%]; P = .484), but the UR was significantly higher in femoral tunnels (mean [SD], 83% [6.2%] vs 74% [10.5%], P = .005). The intraclass correlation coefficients of OR and UR measurements indicated good reliability.

CONCLUSIONS

Allograft bone dowels are a viable graft choice to replenish bone stock in the setting of a staged revision ACL reconstruction. Allograft dowels placed in femoral tunnels had a higher healing union ratio than tibial tunnel allografts and no evidence of degradation at the bone/graft junction, with no difference seen in occupying ratio.

LEVEL OF EVIDENCE

Level IV, case series.

Influence of Preoperative Tunnel Widening On the Outcomes of a Single Stage-Only Approach to Every Revision Anterior Cruciate Ligament Reconstruction: An Analysis of 409 Consecutive Patients From the SANTI Study Group

BACKGROUND

Preoperative tunnel widening is a frequently reported indication for performing a 2-stage revision anterior cruciate ligament reconstruction (ACLR) instead of a single-stage procedure. However, the strength of the available evidence to support a 2-stage strategy is low.

PURPOSE/HYPOTHESIS

The purpose was to evaluate the clinical outcomes of a single stage-only approach to revision ACLR. It was hypothesized that this approach would be associated with significant improvements from baseline in patient-reported outcome measures (PROMs) and knee stability and that there would be no significant differences in any postoperative outcomes between patients with and without preoperative tunnel widening.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

A retrospective analysis was conducted of a large series of consecutive patients undergoing revision ACLR with a minimum follow-up of 2 years. Preoperative tunnel widening was assessed using digital radiographs. All patients underwent single-stage surgery with an outside-in technique, regardless of the degree of tunnel widening. Clinical outcomes were compared according to whether tunnel widening was present (either tunnel ≥12 mm) or not (both tunnels <12 mm).

RESULTS

The study included 409 patients with a mean ± SD follow-up of 69.6 ± 29.0 months. After revision ACLR, there was a significant reduction in the side-to-side anteroposterior laxity difference, from 7.7 ± 2.2 mm preoperatively to 1.2 ± 1.1 mm at 2 years (P < .001). The mean International Knee Documentation Committee (IKDC) and all subscales of the Knee injury and Osteoarthritis Outcome Score (KOOS) exceeded the thresholds for the Patient Acceptable Symptom State defined for primary ACLR. An overall 358 patients had retrievable preoperative radiographs. According to the tunnel diameter measurements, 111 patients were allocated to group A (both tunnels <12 mm) and 247 patients to group B (either/both tunnels ≥12 mm). There were no significant differences between groups with respect to anteroposterior side-to-side laxity difference, graft rupture rates, non-graft rupture related reoperations, or contralateral anterior cruciate ligament injury rates. There was also no significant difference between groups that exceeded minimal detectable change thresholds for any of the PROMs recorded (ACL-RSI [Anterior Cruciate Ligament-Return to Sports After Injury], Lysholm, Tegner, IKDC, KOOS).

CONCLUSION

A single-stage approach to revision ACLR is associated with excellent clinical results when an outside-in drilling technique is utilized. The presence of preoperative tunnel widening does not significantly influence PROMs, knee stability, graft rupture rates, or non-graft rupture related reoperation rates.

Editorial Commentary: Anterior Cruciate Ligament Tunnel Aperture Overlap Determines Need for 1- Versus 2-Stage Revision: Setting the Stage

Despite general agreement that tunnel widening ≥14 mm necessitates a 2-stage approach for revision anterior cruciate ligament (ACL) reconstruction, there is very little literature describing the effect of tunnel overlap between the previous tunnel and new tunnel with 1-stage ACL revisions. Tunnel overlap, particularly at the aperture, should be minimized without compromising anatomic tunnel location(s). This can often be accomplished with a 1-stage revision, but 2-stage revisions are sometimes required. Revision ACL reconstruction can be challenging and it is helpful for the surgeon to carefully plan preoperatively and have several options available to him/her intraoperatively, including the possibility of a 2-stage revision.

The REVision Using Imaging to Guide Staging and Evaluation (REVISE) in ACL Reconstruction Classification

Revision anterior cruciate ligament (ACL) procedures are increasing in incidence and possess markedly inferior clinical outcomes (76% satisfaction) and return-to-sports (57%) rates than their primary counterparts. Given their complexity, a universal language is required to identify and communicate the technical challenges faced with revision procedures and guide treatment strategies. The proposed REV: ision using I: maging to guide S: taging and E: valuation (REVISE) ACL (anterior cruciate ligament) Classification can serve as a foundation for this universal language that is feasible and practical with acceptable inter-rater agreement. A focus group of sports medicine fellowship-trained orthopaedic surgeons was assembled to develop a classification to assess femoral/tibial tunnel "usability" (placement, widening, overlap) and guide the revision reconstruction strategy (one-stage vs. two-stage) post-failed ACL reconstruction. Twelve board-certified sports medicine orthopaedic surgeons independently applied the classification to the de-identified computed tomographic (CT) scan data of 10 patients, randomly selected, who failed ACL reconstruction. An interclass correlation coefficient (ICC) was calculated (with 95% confidence intervals) to assess agreement among reviewers concerning the three major classifications of the proposed system. Across surgeons, and on an individual patient basis, there was high internal validity and observed agreement on treatment strategy (one-stage vs. two-stage revision). Reliability testing of the classification using CT scan data demonstrated an ICC (95% confidence interval) of 0.92 (0.80-0.98) suggesting "substantial" agreement between the surgeons across all patients for all elements of the classification. The proposed REVISE ACL Classification, which employs CT scan analysis to both identify technical issues and guide revision ACL treatment strategy (one- or two-stage), constitutes a feasible and practical system with high internal validity, high observed agreement, and substantial inter-rater agreement. Adoption of this classification, both clinically and in research, will help provide a universal language for orthopaedic surgeons to discuss these complex clinical presentations and help standardize an approach to diagnosis and treatment to improve patient outcomes. The Level of Evidence for this study is 3.

One-Stage Anatomical Revision Anterior Cruciate Ligament Reconstruction: Results According to Tunnel Overlaps

PURPOSE

To present clinical results according to tunnel overlap in 1-stage anatomical revision anterior cruciate ligament reconstruction (ACLR).

METHODS

All patients who underwent revision ACLR performed by a single surgeon (J.H.A.) from 2012 to 2017 and were followed up for >24 months were retrospectively evaluated. The exclusion criteria were concomitant ligament injury, including medial collateral ligament injury, modified Outerbridge grade ≥3 cartilage lesion, and severe meniscus defects. Tunnel overlap was measured on 3-dimensionally reconstructed computed tomography images. Patients in the nonoverlapped femoral tunnel group (group NO, n = 52) were treated with new tunnel drilling that completely avoided previous tunnels, and those in the overlapped femoral tunnel group (group O, n = 41) were treated with a new tunnel that overlapped with previous tunnels. Clinical outcomes were evaluated using the subjective International Knee Documentation Committee (IKDC) and Lysholm scores. Knee joint stability was measured using the Lachman and pivot shift tests. Patients with femoral tunnel widening of ≥14 mm underwent 2-stage ACLR.

RESULTS

The mean follow-up duration of 93 patients was 46.9 months (range, 24-97 months). All preoperative subjective and objective IKDC (P<0.001) and Telos stress test scores (P = .016) were significantly improved at the last follow-up. Forty-one patients had overlapping femoral tunnels, whereas 87 had overlapping tibial tunnels. At the last follow-up, subjective IKDC and Lysholm scores (73.6 ± 15.3 vs 74.9 ± 12.1, P = .799 and 80.0 ± 19.2 vs 81.44 ± 13.5, P = .505, respectively) and objective pivot shift (IKDC grade) in the Lachman test (P = .183 and P = .450, respectively) did not differ significantly between groups NO and O, respectively.

CONCLUSIONS

One-stage anatomical revision ACLR significantly improved the clinical results. Most tibial tunnels (94%) and approximately one-half (44%) of the femoral tunnels overlapped. The overlapped femoral tunnel group did not show inferior outcomes or stability.

LEVEL OF EVIDENCE

Level III, cohort study.

Outcomes of 1- Versus 2-Stage Revision Anterior Cruciate Ligament Reconstruction: A Systematic Review and Meta-analysis

BACKGROUND

Anterior cruciate ligament reconstruction (ACLR) is a common orthopaedic sports medicine procedure, but graft failure is not uncommon and often leads to revision ACLR. Revision surgery can be performed in a 1- or 2-stage fashion.

HYPOTHESIS

Graft failure risk, patient-reported outcomes, and anterior knee laxity are similar after 1- and 2-stage revision ACLR.

STUDY DESIGN

Systematic review; Level of evidence, 4.

METHODS

A systematic review of the literature was performed to evaluate patient outcomes after 1- versus 2-stage revision ACLR. A search was performed with the phrase "revision anterior cruciate ligament reconstruction" across Embase, PubMed, Scopus, and SportDiscus from the beginning of their archives through July 12, 2019.

RESULTS

Thirteen studies met inclusion criteria and included 524 patients: 319 patients who underwent 1-stage revision ACLR and 205 patients who underwent 2-stage revision ACLR. Two studies compared outcomes of 1- versus 2-stage revision ACLR; 4 studies reported outcomes after 2-stage revision ACLR; and the remaining 7 studies documented outcomes after 1-stage ACLR. The mean follow-up was 4.1 years. The 2 studies that compared 1- versus 2-stage ACLR reported no differences in functional, radiologic, or patient-reported outcomes or failure risk. Overall, 9 studies reported subjective International Knee Documentation Committee (IKDC) scores; 4 studies, Knee injury and Osteoarthritis Outcome Score values; 8 studies, Lysholm scores; and 7 studies, Tegner scores; 8 studies measured anterior laxity with a KT-1000 arthrometer. The mean weighted subjective IKDC score for all studies including this outcome at final follow-up was 66.6 for 1-stage revisions and 65.9 for 2-stage revisions.

CONCLUSION

The available evidence comparing 1- versus 2-stage revision ACLR is retrospective and limited. The results of each approach are similar in appropriately selected patients.

Single-Stage Revision Anterior Cruciate Ligament Reconstruction: Experience With 91 Patients (40 Elite Athletes) Using an Algorithm

BACKGROUND

The increased prevalence of anterior cruciate ligament (ACL) reconstruction has led to an increased need for revision ACL reconstructions. Despite the growing body of literature indicating that single-stage revision ACL reconstruction can yield good outcomes, there is a lack of data for determining when and how to safely perform a single-stage revision.

PURPOSE

To assess the outcomes, graft failure rates, and return-to-play rates of a decision-making algorithm for single-stage revision ACL reconstruction.

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

We reviewed a consecutive series of revision ACL reconstructions performed by the senior author between September 2009 and July 2016 with minimum 2-year follow-up. All patients were assessed, and decision making was undertaken according to the algorithm. Outcomes measured were further surgery, graft rerupture, re-revision, Tegner score, and Knee injury and Osteoarthritis Outcome Score (KOOS). For the elite athlete population, return-to-play time, duration, and level of play after surgery as compared with preinjury were also determined.

RESULTS

During this period, 93 procedures were performed in 92 patients (40 elite athletes). Two 2-stage procedures were undertaken, leaving 91 single-stage procedures (91 patients) to form the basis for further study. At a mean 4.3 years (SD, 2.2 years) after surgery, there had been 2 re-revisions (2.2%) and 2 further instances of graft failure that had not been re-revised (total graft failure rate, 4.4%). There were 17 subsequent procedures, including 6 arthroscopic partial meniscectomies, 5 removals of prominent implants, and 1 total knee arthroplasty. The mean Tegner score was 8.02 before graft rerupture and 7.1 at follow-up. At follow-up, the mean KOOS outcomes were 79.3 for Symptoms, 88.0 for Pain, 94.2 for Activities of Daily Living, 73.6 for Sport, and 68.9 for Quality of Life. Of 40 elite athletes, 35 returned to play at a mean 11.2 months (SD, 3.6 months) after surgery.

CONCLUSION

Single-stage revision ACL reconstructions can be performed reliably in the majority of patients, with good clinical outcomes, low rerupture rates, and high-return-to play rates, even in the elite athlete population.

[Mid-term effectiveness of anterior cruciate ligament revision]

Objective

To assess the mid-term effectiveness of anterior cruciate ligament (ACL) revision and to analyze the relevant factors that may affect the surgical outcomes.

Methods

The clinical data of 24 patients who underwent ACL revision surgery between April 2009 and July 2018 and were followed up for more than 2 years were retrospectively analyzed. There were 20 males and 4 females with a median age of 30 years [interquartile distance (IQR) was (25, 36) years]. The median body mass index was 24.45 kg/m ² and IQR was (22.93, 25.93) kg/m ². The median time between ACL revision and reconstruction was 41 months and IQR was (15, 85) months. The direct cause of the failure of reconstruction surgery included 14 cases of trauma, 8 cases of no obvious cause, and 2 cases of infection. During the revision operation, 14 patients had a poor bone tunnel position, all of which were drilled with new tunnels, the remaining 10 patients were freshly modified on the basis of the original bone tunnel. Seventeen patients used autogenous tendon revision, 7 patients used LARS ligament; 16 patients had cartilage injury. The Lysholm score, the International Knee Documentation Committee (IKDC) score, and the Tegner sports rating score were used for functional evaluation before operation, at 1 year after operation, and at last follow-up. The Likert satisfaction score was recorded at last follow-up.

Results

Patients were followed up with a median time of 47 months and IQR was (32, 61) months. The Lysholm score, IKDC score, and Tegner sports rating score were significantly improved at 1 year after operation and at last follow-up when compared with preoperative scores ( P<0.05). There was no significant difference between at last follow-up and at 1 year after operation ( P>0.05). At last follow-up, the median Likert satisfaction score was 4.0 and IQR was (3.0, 4.5). According to the presence or absence of cartilage damage and the type of graft, the above scores at last follow-up were compared between the groups, and the differences were not significant ( P>0.05). At last follow-up, 2 patients had graft fractures due to trauma again, and autogenous iliac bones were taken to fill the bone tunnel, and the second stage was revised; the rest of the patients recovered satisfactorily.

Conclusion

With preoperative identification of the cause of ACL reconstruction failure, the stability and function of knee joint can be significantly improved by selecting appropriate bone tunnels and grafts during the revision and by active rehabilitation exercises.

Beighton Score, Tibial Slope, Tibial Subluxation, Quadriceps Circumference Difference, and Family History Are Risk Factors for Anterior Cruciate Ligament Graft Failure: A Retrospective Comparison of Primary and Revision Anterior Cruciate Ligament Reconstructions

PURPOSE

To assess patient history, physical examination findings, magnetic resonance imaging (MRI) and 3-dimensional computed tomographic (3D CT) measurements of those with anterior cruciate ligament (ACL) graft failure compared with primary ACL tear patients to better discern risk factors for ACL graft failure.

METHODS

We performed a retrospective review comparing patients who underwent revision ACL reconstruction (ACLR) with a primary ACLR group with minimum 1-year follow-up. Preoperative history, examination, and imaging data were collected and compared. Measurements were made on MRI, plain radiographs, and 3D CT. Inclusion criteria were patients who underwent primary ACLR by a single surgeon at a single center with minimum 1-year follow-up or ACL graft failure with revision ACLR performed by the same surgeon.

RESULTS

A total of 109 primary ACLR patients, mean age 33.7 years (range 15 to 71), enrolled between July 2016 and July 2018 and 90 revision ACLR patients, mean age 32.9 years (range 16 to 65), were included. The revision ACLR group had increased Beighton score (4 versus 0; P < .001) and greater side-to-side differences in quadricep circumference (2 versus 0 cm; P < .001) compared with the primary ACLR group. A family history of ACL tear was significantly more likely in the revision group (47.8% versus 16.5%; P < .001). The revision group exhibited significantly increased lateral posterior tibial slope (7.9° versus 6.2°), anterolateral tibial subluxation (7.1 versus 4.9 mm), and anteromedial tibia subluxation (2.7 versus 0.5 mm; all P < .005). In the revision group, femoral tunnel malposition occurred in 66.7% in the deep-shallow position and 33.3% in the high-low position. The rate of tibial tunnel malposition was 9.7% from medial to lateral and 54.2% from anterior to posterior. Fifty-six patients (77.8%) had tunnel malposition in ≥2 positions. Allograft tissue was used for the index ACLR in 28% in the revision group compared with 14.7% in the primary group.

CONCLUSION

Beighton score, quadriceps circumference side-to-side difference, family history of ACL tear, lateral posterior tibial slope, anterolateral tibial subluxation, and anteromedial tibia subluxation were all significantly different between primary and revision ACLR groups. In addition, there was a high rate of tunnel malposition in the revision ACLR group.

Two-Stage Revision Anterior Cruciate Ligament Reconstruction: A Systematic Review of Bone Graft Options for Tunnel Augmentation

BACKGROUND

No consensus is available regarding the optimal choice of bone graft material for bone tunnel augmentation in revision anterior cruciate ligament (ACL) surgery.

PURPOSE

To compare the outcomes of different bone graft materials for staged revision ACL reconstruction.

STUDY DESIGN

Systematic review.

METHODS

A systematic review using PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines was performed. PubMed, EMBASE, and the Cochrane Library were queried through use of the terms anterior cruciate ligament and revision to identify all studies reporting outcomes of bone tunnel grafting in 2-stage revision ACL reconstruction. Data extracted included indications for 2-stage surgery, surgical technique, graft material, time between surgeries, rehabilitation protocols, physical examination findings, patient-reported outcomes, and radiographic and histologic findings.

RESULTS

The analysis included 7 studies with a total of 234 patients. The primary outcome in 2 studies was graft incorporation (mean follow-up, 8.8 months), whereas the other 5 studies reported clinical outcomes with follow-up mean ± SD of 4.2 ± 2.1 years. The indication for bone grafting and between-stage protocol varied among studies. Autograft was used in 4 studies: iliac crest bone autograft (ICBG, n = 3) and tibial bone autograft (TBA, n = 1). In 2 studies, the authors investigated the outcomes of allograft: allograft bone matrix (ABM) and allograft bone chips (AC). Finally, 1 study compared ICBG to a synthetic bone substitute. Radiographic evaluation of bone graft integration after the first stage was reported in 4 studies, with an average duration of 4.9 months. In 4 studies, the authors reported the time interval between first and second surgeries, with an average of 6.1 months for ICBG compared with 8.7 months for allogenic and synthetic grafts. Revision ACL graft failure rates were reported by 5 studies, including 1 study with ABM (6.1%), 1 study with AC (8.3%), 1 study with TBA (0%), and 2 studies with ICBG (0% and 2%).

CONCLUSION

The indications for staged ACL reconstruction and the rehabilitation protocol between stages need to be clearly established. The available data indicate that autograft for bone tunnel grafting in 2-stage ACL revision may be associated with a lower risk of revision ACL reconstruction graft failure compared with allograft bone.

Autologous Bone Graft Versus Silicate-Substituted Calcium Phosphate in the Treatment of Tunnel Defects in 2-Stage Revision Anterior Cruciate Ligament Reconstruction: A Prospective, Randomized Controlled Study With a Minimum Follow-up of 2 Years

PURPOSE

To compare and evaluate knee laxity and functional outcomes between autologous bone graft and silicate-substituted calcium phosphate (Si-CaP) in the treatment of tunnel defects in 2-stage revision anterior cruciate ligament reconstruction (ACLR).

METHODS

This prospective, randomized controlled trial was conducted between 2012 and 2015 with a total of 40 patients who underwent 2-stage revision ACLR. The tunnels were filled with autologous iliac crest cancellous bone graft in 20 patients (control group) and with Si-CaP in the other 20 patients (intervention group). After a minimum follow-up period of 2 years, functional outcomes were assessed by KT-1000 arthrometry (side-to-side [STS] difference), the Tegner score, the Lysholm score, and the International Knee Documentation Committee score.

RESULTS

A total of 37 patients (follow-up rate, 92.5%) with an average age of 31 years were followed up for 3.4 years (range, 2.2-5.5 years). The KT-1000 measurement did not show any STS difference between the bone graft group (0.9 ± 1.5 mm) and the Si-CaP group (0.7 ± 2.0 mm) (P = .731). One patient in the intervention group (5%) had an STS difference greater than 5 mm. Both groups showed significant improvements in the Tegner score, Lysholm score, and International Knee Documentation Committee score from preoperative assessment to final follow-up (P ≤ .002), without any difference between the 2 groups (P ≥ .396). Complications requiring revision occurred in 4 control patients (22%) and in 2 patients in the intervention group (11%) (P = .660). No complications in relation to Si-CaP were observed.

CONCLUSIONS

Equivalent knee laxity and clinical function outcomes were noted 3 years after surgery in both groups of patients. Si-CaP bone substitute is therefore a safe alternative to autologous bone graft for 2-stage ACLR.

LEVEL OF EVIDENCE

Level I, prospective, randomized controlled clinical trial.

Incidence and Healing Rates of Meniscal Tears in Patients Undergoing Repair During the First Stage of 2-Stage Revision Anterior Cruciate Ligament Reconstruction

BACKGROUND

Meniscal tears, including tears at the root attachment, have been associated with tears of the anterior cruciate ligament (ACL) in both primary and revision settings. However, there is a paucity of literature reporting the healing rates of meniscal repair during 2-stage revision ACL reconstruction (ACLR).

PURPOSE

To evaluate the healing rates of meniscal repairs performed during 2-stage revision ACLR in ACL-deficient knees and to report the incidence of meniscus root tears in patients undergoing primary ACLR as compared with revision ACLR.

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

Patients who underwent primary and revision ACLR by a single surgeon were retrospectively identified. Revision ACLRs were grouped according to 1- or 2-stage ACLR. Meniscal tears were grouped according to laterality (medial, lateral) and location of tears. Meniscal repair technique was recorded, including transtibial or inside-out. Meniscal repair healing was assessed via second-look arthroscopy at the time of second-stage revision ACLR.

RESULTS

There were 1168 patients identified who underwent ACLR: 851 primary and 317 revision procedures. Sixty-four patients underwent meniscal repair during first-stage bone grafting in ACL-deficient knees, with an overall healing rate of 86%. The healing rates were 82.3% for meniscus root tears via the transtibial repair technique and 92.4% for meniscal peripheral tears via the inside-out repair technique. Meniscus root tears had overall incidences of 15.5% and 26.2% in primary and revision ACLRs, respectively. The incidence of lateral meniscus posterior root tears was approximately 4 times higher than of medial meniscus posterior root tears in both primary (12.2% vs 3.2%) and revision (20.5% vs 5.6%) ACLRs.

CONCLUSION

A high incidence of meniscus root tears was found in patients undergoing revision ACLRs as compared with primary ACLRs. Meniscal repairs have a high rate of healing and success when performed during the first stage of revision ACLR in ACL-deficient knees.

Two-stage revision anterior cruciate ligament reconstruction

With the rising number of anterior cruciate ligament (ACL) reconstructions, revision ACL reconstructions are becoming increasingly common. A revision procedure may be performed to improved knee function, correct instability, and facilitate a return to normal activities. When performing a revision reconstruction, the surgeon decides between a single-stage or a two-stage revision. Two-stage revisions are rarely performed, but are particularly useful when addressing substantial tunnel-widening, active infection, and concomitant knee pathology (e.g., malalignment, other ligamentous injuries, meniscal or chondral lesions). Among these potential scenarios requiring a two-stage revision, tunnel-widening is the most common cause; the first stage involves graft removal, tunnel curettage, and bone grafting, followed by revision ACL reconstruction in the second stage. The purpose of this article is to review the preoperative planning, surgical considerations, rehabilitation, and outcomes of two-stage revision ACL reconstructions and summarize the recent literature outlining treatment results.

Revision anterior cruciate ligament reconstruction restores knee laxity but shows inferior functional knee outcome compared with primary reconstruction

PURPOSE

To evaluate and compare knee laxity and functional knee outcome between primary and revision anterior cruciate ligament (ACL) reconstruction in the same cohort of patients.

METHODS

Patients who underwent primary and revision ACL reconstruction (ACLR) at Capio Artro Clinic, Stockholm, Sweden, from 2000 to 2015, were identified in our local database. Inclusion criteria were: same patients who underwent primary hamstring tendons (HT) and revision bone-patellar tendon-bone (BPTB) autograft ACLR, no associated ligament injuries and no contralateral ACL injuries/reconstructions. The cause of revision ACLR was graft rupture for all patients. The KT-1000 arthrometer, with an anterior tibial load of 134-N, was used to evaluate knee laxity preoperatively and 6-month postoperatively. The Knee Injury and Osteoarthritis Outcome Score (KOOS) was collected preoperatively and at the 1-year follow-up.

RESULTS

A total of 118 patients with primary and revision ACLR arthrometric laxity measurements were available (51.0% males; mean age at primary ACLR 21.7 ± 7.1 years and revision ACLR 24.3 ± 7.5 years). The mean preoperative and postoperative anterior side-to-side (STS) difference values were not significantly different between primary and revision ACLR. However, primary ACLR showed a significantly higher frequency of postoperative anterior STS difference > 5 mm compared with revision ACLR (8.4 vs 5.0%; P = 0.02). The KOOS was available for primary and revision ACLR for 73 patients (55.4% males; mean age at primary ACLR 21.6 ± 7 years and revision ACLR 24.7 ± 7.3 years). Preoperatively, revision ACLR showed significantly higher scores in all KOOS subscales, except for the activity of daily living (ADL) subscale. For the primary ACLR, the improvement from preoperatively to the 1-year follow-up was significantly greater in all KOOS subscales and, the postoperative scores were superior for Pain, ADL and Sports subscales compared with revision ACLR.

CONCLUSIONS

The findings of this study showed that anterior knee laxity is restored with revision BPTB autograft ACLR after failed primary HT autograft ACLR, in the same cohort of patients. However, revision ACLR showed a significantly inferior functional knee outcome compared with primary ACLR. It is important for clinicians to inform and set realistic expectations for patients undergoing revision ACLR. Patients must be aware of the fact that having revision ACLR their knee function will not improve as much as with primary ACLR and the final postoperative functional outcome is inferior.

LEVEL OF EVIDENCE

Retrospective cohort study, Level III.

Single-stage versus two-stage revision anterior cruciate ligament reconstruction: a systematic review

Importance

Despite advances in surgical techniques and postoperative rehabilitation, long-term anterior cruciate ligament (ACL) graft rupture rate remains high. The increasing number of primary ACL reconstructions in an ageing population will lead to increasing revision reconstructions. Revision cases may have higher failure rates and worse patient-reported outcomes compared with primaries. While two-stage revisions may be indicated in certain complex cases, whether this is comparatively equivalent or even superior to revisions done in a single stage would assist preoperative planning.

Objective

The objective of this systematic review was to analyse and compare patient-reported outcomes and failure rate of single-stage versus two-stage revision ACL reconstruction.

Evidence review

Using PubMed, MEDLINE Complete and Ovid MEDLINE databases, a review was performed using Preferred Reporting Items for Systematic Reviews and Meta-analysis guidelines to identify level I–IV outcomes of revision ACL reconstruction with a minimum follow-up of 24 months.

Findings

Three studies reported outcomes of two-stage revisions with mean follow-up of 61.6 months, while 21 studies reported single-stage revisions with mean follow-up of 47.4 months. Pooled rate of two-stage revisions was 3.1% compared with 6.8% in single-stage (p=0.068). Clinical failure was reported in 5.1% of 79 two-stage patients compared with 13.8% of 533 single-stage patients (p<0.05). Within the single-stage cohort, there was a greater clinical failure rate (+8.7%, p<0.05) for patients with less than 48 months follow-up. Those with > 48 months follow-up had a higher rerupture rate (+5%, p<0.05) and a significantly greater sum of squared deviations (p<0.05) compared with those with < 48 months follow-up. Patient-reported outcomes have demonstrated two-stage revision patients with higher IKDC A and B scores than single-stage.

Conclusions and relevance

Although two-stage revisions may be performed in more complex cases, there are limited short-term data available regarding their outcomes. Two-stage revisions demonstrated comparable clinical outcomes and lower rate of revision surgery and clinical failure compared with single-stage revisions. Studies with shorter follow-up (24–48 months) showed higher clinical failure rates. Those with longer follow-up (>48 months) showed higher graft rerupture rates. The decision to perform staged reconstruction should made on whether adequate tunnel placement and fixation can be established in a single setting.

Level of evidence

Level IV.

One-Stage Revision Anterior Cruciate Ligament Reconstruction: Results According to Preoperative Bone Tunnel Diameter: Five to Fifteen-Year Follow-up

BACKGROUND

Bone tunnel enlargement is one of the important factors that determine whether a revision anterior cruciate ligament reconstruction (ACLR) should be performed in 1 or 2 stages. The goal of this retrospective cohort study was to compare the mid-term to long-term outcomes of 1-stage revision ACLR according to the amount of preoperative tunnel enlargement.

METHODS

Between January 2002 and January 2012, 88 patients who underwent revision ACLR were enrolled. The patients were divided into 2 groups based on the tunnel diameter (group A, <12 mm; group B, ≥12 mm). Clinical scores (International Knee Documentation Committee [IKDC] subjective score, Lysholm score, and Tegner score) and knee joint stability (as measured with the anterior drawer test, Lachman test, pivot-shift test, and measurement of the side-to-side difference in anterior tibial translation on Telos stress radiographs) were evaluated preoperatively and 5 to 15 years postoperatively. The failure rate and survivorship were compared between groups A and B.

RESULTS

The mean time to final follow-up was 7.9 ± 2.6 years. There were 44 patients in each of the 2 groups. There were no significant differences in the postoperative IKDC subjective scores, Lysholm scores, or Tegner activity scores between the groups. However, group A showed superior results on all knee joint stability tests except for the anterior drawer test. There were 3 failures in group A (7%) and 6 in group B (14%). The overall survival rates with failure as the end point were 93.1% and 84.6%, respectively, at 15 years.

CONCLUSIONS

The 5 to 15-year clinical scores following revision ACLR did not differ significantly according to the preoperative amount of tunnel widening. However, the results of the postoperative Lachman and pivot-shift tests as well as the side-to-side difference in anterior tibial translation on Telos stress radiographs were significantly superior in the group with a preoperative tunnel diameter of <12 mm compared with the group with a tunnel diameter of ≥12 mm.

LEVEL OF EVIDENCE

Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.