Osteoarthritic changes after anterior cruciate ligament reconstruction using bone-patellar tendon-bone or hamstring tendon autografts: a retrospective, 7-year radiographic and clinical follow-up study

Current concepts and new trends in management of isolated triangular fibrocartilage complex injuries

The triangular fibrocartilaginous complex is made of multiple components, of which the palmar and dorsal radioulnar ligaments play an important role in distal radioulnar joint stability. The ulnar wrist ligaments may be injured during forearm and wrist trauma. There are several aspects of triangular fibrocartilaginous complex management that are still open to debate. The aim of the present study was to review the current concepts and discuss emerging trends to better elucidate and treat this important ligament complex.Level of evidence: V.

Comparative study of functional outcomes of arthroscopic anterior cruciate ligament reconstruction using anteromedial portal and translateral all-inside technique

Background

Anterior Cruciate Ligament (ACL) injuries are common in the active population of the Armed Forces. Symptomatic instability prompts individuals to seek a cure or a sheltered appointment. Despite the increasing numbers of ACL reconstructions performed, the outcomes have not been so spectacular with only a meager percentage of our patients returning to preinjury levels of activity. With the premise that an all-inside ACL reconstruction is likely to result in better functional outcomes, the aim of this study was to compare the short-term functional outcomes of a large consecutive series of patients undergoing ACL reconstruction using the translateral all-inside ACL reconstruction technique (AI) and standard anteromedial portal technique (AM) with a minimum follow-up of one year.

Methods

A total of 240 patients with isolated ACL tear underwent ACL reconstruction via the AI or AM technique. Their preoperative and postoperative scores were compared to look for any significant differences in functional outcomes.

Results

The two groups were matched for age, BMI, mechanism of injury, and interval from injury to surgery. There was no difference in their preoperative scores. Postoperatively, although there were significant improvements across both groups, there was no significant difference between the groups at any point of time.

Conclusion

The AI technique has garnered interest in recent literature in addressing ACL injuries. This study found no discernible benefit of the AI technique when compared to the AM technique in terms of functionality following an ACL reconstruction at any point of time up to 1 year following surgery.

Anatomic Double-Bundle Anterior Cruciate Ligament Reconstruction Is Not Superior to Anatomic Single-Bundle Reconstruction at 10-Year Follow-up: A Randomized Clinical Trial

BACKGROUND

The anatomic double-bundle (DB) technique is purported to be a superior technique due to its mimicking of the double-stranded anatomic formation of the anterior cruciate ligament (ACL). Previous studies with 2-, 5- and 10-year follow-up are conflicted as to whether this technique is superior to the previous gold standard method of ACL reconstruction, the anatomic single-bundle (SB) reconstruction.

PURPOSE/HYPOTHESIS

The aim of this prospective randomized study was to compare the outcomes of the anatomic DB technique and anatomic SB technique with independent drilling at 10 years after anterior cruciate ligament (ACL) reconstruction. We hypothesized that DB ACL reconstruction would result in a better outcome in terms of the pivot-shift test.

STUDY DESIGN

Randomized controlled trial; Level of evidence, 1.

METHODS

A total of 105 patients (33 women, 72 men; median age, 27 years [range, 18-52 years]) were randomized and underwent ACL reconstruction (DB group: n = 53; SB group: n = 52). All reconstruction procedures were performed anatomically by identifying the ACL footprint, using the anteromedial portal for femoral tunnel drilling, and utilizing interference screws for tibial and femoral fixation. One blinded observer examined the patients both preoperatively and at follow-up (median, 120 months [range, 112-134 months]). Multiple subjective and objective clinical evaluations were used to assess the outcomes. Radiographic assessments of osteoarthritis were performed using the Ahlbäck, Kellgren-Lawrence, and Fairbank classification systems early postoperatively and at the final follow-up.

RESULTS

Preoperatively, no differences were found between the study groups. Overall, 70 patients (67%; DB group: n = 39; SB group: n = 31) were available for analysis at 10-year follow-up. No significant difference could be shown between the groups in terms of the pivot-shift grade, knee laxity measurements using the KT-1000 arthrometer, manual Lachman grade, single-leg hop test result, range of motion measurements, Lysholm knee score, Tegner activity score, and Knee injury and Osteoarthritis Outcome Score (KOOS) score. Correspondingly, no differences were found between the groups regarding the presence of radiographic osteoarthritis at follow-up. Both groups improved at follow-up compared with preoperatively in terms of the pivot-shift grade, knee laxity measurements using the KT-1000 arthrometer, manual Lachman grade, Lysholm knee score, and KOOS score (P < .05 [highest P value for any comparison]).

CONCLUSION

The anatomic DB technique was not superior to the anatomic SB technique with independent drilling at 10-year follow-up in regard to objective and subjective measurements. As such, one could argue that there is no need for the continued use of the anatomic DB technique in an unselected population.

Polydopamine Coating-Mediated Immobilization of BMP-2 on Polyethylene Terephthalate-Based Artificial Ligaments for Enhanced Bioactivity

Background/objectives: Polyethylene terephthalate (PET)-based artificial ligaments are one of the most commonly used grafts in anterior cruciate ligament (ACL) reconstruction surgery. However, the lack of favorable hydrophilicity and cell attachment for PET highly impeded its widespread application in clinical practice. Studies found that surface modification on PET materials could enhance the biocompatibility and bioactivity of PET ligaments. In this study, we immobilized bone morphogenetic protein-2 (BMP-2) on the surface of PET ligaments mediated by polydopamine (PDA) coating and investigated the bioactivation and graft-to-bone healing effect of the modified grafts in vivo and in vitro.

Methods: In this study, we prepared the PDA coating and subsequent BMP-2-immobilized PET artificial ligaments. Scanning electron microscopy (SEM) was used to analyze the morphological changes of the modified grafts. In addition, the surface wettability properties of the modified ligaments, amount of immobilized BMP 2, and the release of BMP-2 during a dynamic period up to 28 days were tested. Then, the attachment and proliferation of rat bone mesenchymal stem cells (rBMSCs) on grafts were examined by SEM and Cell Counting Kit-8 (CCK-8) assay, respectively. Alkaline phosphatase (ALP) assay, RT-PCR, and Alizarin Red S staining were performed to test the osteoinduction property. For in vivo experiments, an extra-articular graft-to-bone healing model in rabbits was established. At 8 weeks after surgery, biomechanical tests, micro-CT, and histological staining were performed on harvested samples.

Results: A surface morphological analysis verified the success of the PDA coating. The wettability of the PET artificial ligaments was improved, and more than 80% of BMP-2 stably remained on the graft surface for 28 days. The modified grafts could significantly enhance the proliferation, attachment, as well as expression of ALP and osteogenic-related genes, which demonstrated the favorable bioactivity of the grafts immobilized with BMP-2 in vitro. Moreover, the grafts immobilized with BMP-2 at a concentration of 138.4 ± 10.6 ng/cm² could highly improve the biomechanical properties, bone regeneration, and healing between grafts and host bone after the implantation into the rabbits compared with the PDA-PET group or the PET group.

Conclusion: The immobilization of BMP-2 mediated by polydopamine coating on PET artificial ligament surface could enhance the compatibility and bioactivity of the scaffolds and the graft-to-bone healing in vivo.

Positive effects of platelet-rich plasma (PRP) and a Sanguisorba officinalis polysaccharide on the proliferation and differentiation of anterior cruciate ligament (ACL) fibroblasts in vitro

Context: Sanguisorba officinalis L. (Rosaceae), a famous traditional Chinese medicine. It was recently reported that its polysaccharide could facilitate collagen production.Objectives: We investigated the mechanism by which S. officinalis polysaccharide (SOWPa) and/or platelet-rich plasma (PRP) promote regenerative potential of anterior cruciate ligament (ACL) in vitro.Materials and methods: ACL fibroblasts were treated with SOWPa (25 and 100 mg/kg), PRP, PRP + SOWPa (25 and 100 mg/kg) or vehicle alone for 24, 48, or 72 h. Cell viability, migration ability and apoptosis were evaluated by MTT, transwell and flow cytometry, respectively. Western blot analysis was performed to assess associated protein expression.Results: PRP, SOWPa (100 mg/kg) or PRP + SOWPa (100 mg/kg) treatment for 72 h significantly improved the cell viability of ACL fibroblasts from 100 ± 7.5% (control) to 156.85 ± 12.82%, 188.08 ± 15.92%, and 223.67 ± 18.82%, respectively, which was evidenced by individual decreased apoptosis rate from 31.26 ± 2.35% (control) to 20.80 ± 1.89%, 18.01 ± 1.55% and 9.33 ± 0.78%. Furthermore, the motility of ACL fibroblasts was significantly improved with increased migrated cell number per field from 5 for control to 26 for PRP, 36 for SOWPa and 44 for PRP + SOWPa, respectively. Moreover, the protein expression of differentiation markers (RUNX2, ALP, BMP2 and Col I) and TLR-4 and phosphorylated p65 (p-p65) was inhibited by the above treatment.Discussion and conclusions: Data suggested that the addition of SOWPa to PRP increased the regenerative ability of ACL fibroblasts by blocking the TLR-4/NF-κB pathway.

Clinical and radiological results after Internal Brace suture versus the all-inside reconstruction technique in anterior cruciate ligament tears 12 to 18 months after index surgery

BACKGROUND

 Anterior cruciate ligament (ACL) injury can lead to reduced function, meniscal lesions, and early joint degeneration. Preservation of a torn ACL using the Internal Brace technique might re-establish normal knee kinematics, avoid donor-site morbidity due to tendon harvesting, and potentially maintain proprioception of the knee.

METHODS

 Fifty subjects were recruited for this study between December 2015 and October 2016. Two groups of individuals who sustained a unilateral ACL rupture were included: those who underwent surgery with preservation of the injured ACL (Internal Brace technique; IB) and those who underwent ACL reconstruction using a hamstring tendon graft (all-inside technique; AI). Subjective self-administered scores were used: the German version of the IKDC Subjective Knee Form (International Knee Documentation Committee), the German version of the WOMAC (Western Ontario and McMaster Universities Arthritis Index), SF-36 (short form), the German version of the KOOS (Knee Osteoarthritis Outcome Score), and the German version of themodified Lysholm Score by Lysholm and Gillquist. Anterior tibial translation was assessed using the KT-1000 Arthrometer (KT-1000 Knee Ligament Arthrometer, MEDmetric Corp., San Diego, CA, USA). Magnetic resonance evaluation was performed in all cases.

RESULTS

 Twenty-three subjects (46 %) were men, and the mean age was 34.7 years. The objective IKDC scores were "normal" in 15 and 14 patients, "nearly normal" in 11 and 7 patients, and "abnormal" in 1 and 2 patients, in the IB and AI groups, respectively. KT-1000 assessment showed a sideto-side difference of more than 3 mm on maximum manual testing in 11 (44 %) and 6 subjects (28.6 %) in the IB and AI groups, respectively. In the postoperative MRI, 20 (74 %) and 22 subjects (96 %) in the IB and AI groups had an intact ACL. Anterior tibial translation was significantly higher in the IB group compared with the AI group in the manual maximum test.

CONCLUSIONS

 Preservation of the native ACL with the Internal Brace primary repair technique can achieve comparable results to ACL reconstruction using Hamstring autografts over a short term. Clinically relevant limitations such as a higher incidence of pathologic laxity, with patients more prone to pivot-shift phenomenon were observed during the study period.

Poor Associations Between Radiographic Tibiofemoral Osteoarthritis and Patient-Reported Outcomes at 16 Years After Anterior Cruciate Ligament Reconstruction

Background

Radiographic tibiofemoral (TF) osteoarthritis (OA) is common in patients after anterior cruciate ligament (ACL) reconstruction at long-term follow-up. The association between radiographic OA and patient-reported outcomes has not been thoroughly investigated.

Purpose

To determine the association between radiographic TF OA and patient-reported outcome measure (PROM) scores at 16 years after ACL reconstruction.

Study Design

Case-control study; Level of evidence, 3.

Methods

This study was based on 2 randomized controlled studies comprising 193 patients who underwent unilateral ACL reconstruction. A long-term follow-up was carried out at 16.4 ± 1.7 years after surgery and included a radiographic examination of the knee and recording of PROM scores. Correlation analyses were performed between radiographic OA (Kellgren-Lawrence [K-L], Ahlbäck, and cumulative Fairbank grades) and the PROMs of the International Knee Documentation Committee (IKDC) subjective knee form, Lysholm score, and Tegner activity scale. A linear univariable regression model was used to assess how the IKDC score differed with each grade of radiographic OA.

Results

Of 193 patients at baseline, 147 attended the long-term follow-up. At long-term follow-up, 44.2% of the patients had a K-L grade of ≥2 in the injured leg, compared with 6.8% in the uninjured leg. The mean IKDC score at follow-up was 71.2 ± 19.9. Higher grades of radiographic OA were significantly correlated with lower IKDC and Lysholm scores (r = -0.36 to -0.22). Patients with a K-L grade of 3 to 4 had significantly lower IKDC scores compared with patients without radiographic OA (K-L grade 0-1). Adjusted beta values were -15.7 (95% CI, -27.5 to -4.0; P = .0093; R ² = 0.09) for K-L grade 3 and -25.2 (95% CI, -41.7 to -8.6; P = .0033; R ² = 0.09) for K-L grade 4.

Conclusion

There was a poor but significant correlation between radiographic TF OA and more knee-related limitations, as measured by the IKDC form and the Lysholm score. Patients with high grades of radiographic TF OA (K-L grade 3-4) had a statistically significant decrease in IKDC scores compared with patients without radiographic TF OA at 16 years after ACL reconstruction. No associations were found between radiographic TF OA and the Tegner activity level.

Patellar Tendon Versus 4-Strand Semitendinosus and Gracilis Autografts for Anterior Cruciate Ligament Reconstruction: A Meta-analysis of Randomized Controlled Trials With Mid- to Long-Term Follow-Up

PURPOSE

To compare patellar tendon (PT) autografts with 4-strand semitendinosus and gracilis (STG) autografts concerning knee stability, functional outcomes, as well as complications after anterior cruciate ligament (ACL) reconstruction at minimal follow-up of 5 years.

METHODS

A systematic search of the literature was performed in PubMed, Embase, and the Cochrane Library to identify published prospective randomized controlled trials on clinical studies comparing PT autograft and 4-strand STG autografts for ACL reconstruction. The results of the eligible studies were analyzed in terms of knee stability (laxity measurements, Lachman test, and pivot-shift test), functional outcomes (Lysholm score, International Knee Documentation Committee score, Cincinnati score, Tegner score, single-legged hop test, and return to preinjury activity level), and complications (loss of range of motion [ROM], pain, graft re-rupture, revision, and osteoarthritis [OA]).

RESULTS

Nine clinical studies with 630 patients (313 PT and 317 STG autografts) met the inclusion criteria. No statistically significant differences were found between the PT and STG group in Lachman test, pivot-shift test, International Knee Documentation Committee score, Cincinnati score, loss of ROM, kneeling pain, graft re-rupture rate, revision rate, and OA rate. The STG group was found with less anterior knee pain (P = .003). There were no clinically significant differences for the outcomes of SSD, Lysholm score, and Tegner score.

CONCLUSIONS

Except for significantly greater risk of anterior knee pain, PT autograft had comparable results with 4-strand STG autograft in terms of knee stability and functional outcomes after ACL reconstruction with mid- to long-term follow-up. Besides, we found no statistically significant difference in loss of ROM, kneeling pain, graft re-rupture rate, revision rate, and OA change, but these results were underpowered.

LEVEL OF EVIDENCE

Level I, meta-analysis of Level I studies.

Higher Physiologic Platelet Counts in Whole Blood Are Not Associated With Improved ACL Cross-sectional Area or Signal Intensity 6 Months After Bridge-Enhanced ACL Repair

Background:

A bridge-enhanced anterior cruciate ligament (ACL) repair (BEAR) procedure places an extracellular matrix implant, combined with autologous whole blood, in the gap between the torn ends of the ligament at the time of suture repair to stimulate healing. Prior studies have suggested that white blood cell (WBC) and platelet concentrations significantly affect the healing of other musculoskeletal tissues.

Purpose/Hypothesis:

The purpose of this study was to determine whether concentrations of various blood cell types placed into a bridging extracellular matrix implant at the time of ACL repair would have a significant effect on the healing ligament cross-sectional area or tissue organization (as measured by signal intensity). We hypothesized that patients with higher physiologic platelet and lower WBC counts would have improved healing of the ACL on magnetic resonance imaging (MRI) (higher cross-sectional area and/or lower signal intensity) 6 months after surgery.

Study Design:

Cohort study; Level of evidence, 2.

Methods:

A total of 61 patients underwent MRI at 6 months after bridge-enhanced ACL repair as part of the BEAR II trial. The normalized signal intensity and average cross-sectional area of the healing ligament were measured from a magnetic resonance stack obtained using a gradient echo sequence. The results were stratified by sex, and univariate and multivariate regression analyses determined significant correlations between blood cell concentrations on these 2 magnetic resonance parameters.

Results:

In unadjusted analyses, older age and male sex were associated with greater healing ligament cross-sectional area (P < .04) but not signal intensity (P > .15). Adjusted multivariable analyses indicated that in female patients, a higher monocyte concentration correlated with a higher ACL cross-sectional area (β = 1.01; P = .049). All other factors measured, including the physiologic concentration of platelets, neutrophils, lymphocytes, basophils, and immunoglobulin against bovine gelatin, were not significantly associated with either magnetic resonance parameter in either sex (P > .05 for all).

Conclusion:

Although older age, male sex, and monocyte concentration in female patients were associated with greater healing ligament cross-sectional area, signal intensity of the healing ligament was independent of these factors. Physiologic platelet concentration did not have any significant effect on cross-sectional area or signal intensity of the healing ACL at 6 months after bridge-enhanced ACL repair in this cohort. Given these findings, factors other than the physiologic platelet concentration and total WBC concentration may be more important in the rate and amount of ACL healing after bridge-enhanced ACL repair.

Biomechanical comparison of single-bundle versus double-bundle anterior cruciate ligament reconstruction: a meta-analysis

BACKGROUND

Of the many issues regarding surgical techniques related to anterior cruciate ligament reconstruction (ACLR), single-bundle (SB) or double-bundle (DB) ACLR is one of the most debated topics. However, it is unclear which of the techniques yields better outcomes after ACLR for ACL injury. The purpose of this meta-analysis was to compare the benefits of SB versus DB ACLR in terms of biomechanical outcomes.

METHODS

The electronic databases MEDLINE, Embase, the Cochrane Central Register of Controlled Trials, Web of Science, and Scopus were searched for relevant articles comparing the outcomes of SB-ACLR versus DB-ACLR that were published until November 2019.

RESULTS

Seventeen biomechanical studies were included. The anterior laxity measured using the anterior drawer test showed significantly better results in DB-ACLR when compared with SB-ACLR. In addition, outcomes of the anterior tibial translation test under a simulated pivot shift presented with better results at low flexion and 30° in DB-ACLR, compared with SB-ACLR. However, there were no significant biomechanical differences between the groups in internal rotation.

CONCLUSIONS

The present study demonstrated that both techniques for ACLR are associated with restoration of normal knee kinematics. DB-ACLR is superior to SB-ACLR in terms of restoration of anteroposterior stability. However, which technique yields better improvement in internal rotation laxity, and internal rotation laxity under a simulated pivot shift at a specific angle, remains unclear.

LEVEL OF EVIDENCE

This is a level II meta-analysis.

Early chondral damage following meniscus repairs with anterior cruciate ligament reconstruction

Background

Meniscal tears are commonly observed in patients with anterior cruciate ligament (ACL) injuries. Meniscal repair has become a common procedure for the injured meniscus, and good clinical outcomes have been reported in such cases when used concurrently with ACL reconstruction. However, it is unclear whether early chondral damage progression can be prevented following meniscal repair with ACL reconstruction, as meniscal damage is a potential risk factor for the development of osteoarthritis. The purpose of this study was to evaluate the zone-specific chondral damage that occurs after arthroscopic meniscal repair with concomitant ACL reconstruction. Our hypothesis was that meniscal repair with ACL reconstruction would not decrease the rate of progression of chondral damage compared to that observed in isolated ACL reconstruction with intact menisci.

Methods

This study included 40 patients who underwent anatomic double-bundle ACL reconstruction. We divided the patients into the following two groups: Group A with an intact meniscus (20 knees) and Group M requiring meniscal repair (20 knees). Chondral damage was evaluated arthroscopically in six compartments and 40 sub-compartments, and these features were graded using the International Cartilage Repair Society lesion classification. The cartilage damage in each sub-compartment and compartment was compared between the two groups both at reconstruction and at second-look arthroscopy (average 16 months postoperatively). At the latest follow-up examination (average 37 months postoperatively), the International Knee Documentation Committee (IKDC) score was compared between the two groups.

Results

Group M had a significantly worse cartilage status than Group A in five sub-compartments (mainly in the medial compartment) at reconstruction and in nine sub-compartments (mainly in the bilateral compartments) at second-look arthroscopy. The mean IKDC score was better in Group A than in Group M (Group A; 90 vs. Group M; 86). The overall success rate of meniscal repairs was 92% (23 of 25 menisci) at second-look arthroscopy.

Conclusion

The progression of post-traumatic chondral damage may occur at a faster rate in patients who require ACL reconstruction and meniscal repair than in patients with intact menisci.

Prevalence of patellofemoral joint osteoarthritis after anterior cruciate ligament injury and associated risk factors: A systematic review

Background

The prevalence of patellofemoral joint (PFJ) osteoarthritis (OA) after anterior cruciate ligament (ACL) injury was inconsistently reported in the literature. This review summarises the reported prevalence of PFJ OA and risk factors of PFJ OA after ACL injury.

Methods

PubMed, Embase, WoS, and MEDLINE (OVID) were searched up to 1 March 2019. A modified version of the Coleman methodology score was used to assess the methodological quality of the included studies. Prevalence of PFJ OA was pooled depended on different interventions in ACL injured populations.

Results

Thirty-eight studies were included. Five different radiographic classification methods were used: the Kellgren and Lawrence Grade 2, IKDC Grade B, Fairbank Grade 1, joint space narrowing of Grade 2 based on OARSI, and Ahlbäck Grade 1. One included study used MRI Osteoarthritis Knee Score to evaluate PFJ degenerative changes. The overall prevalence of PFJ OA after ACL injury in included studies varied between 4.5% and 80%. The large variation of PFJ OA prevalence is mainly because of different follow-up period and surgical techniques. The pooled data showed that bone-patellar tendon-bone graft, single-bundle ACL reconstruction (ACLR), and delayed ACLR are likely associated with PFJ degenerative changes after ACL injury. ACLR, delayed ACLR, body mass index (BMI), meniscectomy, patellofemoral chondral lesions, age at surgery, and TFJ OA were identified in the literature inducing PFJ OA after ACL injury.

Conclusions

Large variations of PFJ OA after ACL injury are associated with different follow-up period and surgical techniques. ACL reconstructed population with bone-patellar tendon-bone graft, single-bundle reconstruction, and delayed operation time has a high prevalence of PFJ OA.

The translational potential of this article

This review focuses more on the effect of surgical technique factors on the degenerative changes on PFJ. The results reveal that BPTB, single-bundle reconstruction, and delayed ACLR are more likely associated with PFJ degenerative changes after ACL injury. These findings imply that awareness of PFJ problems after surgical intervention will remind of surgeons taking PFJ into consideration in operations, which is likely to reduce the incidences of anterior knee pain, patellar maltracking, and over-constrained patella in the early stage after surgery.

Activity-related outcome in anterior cruciate ligament reconstruction with synthetic ligament advanced reinforcement system

BACKGROUND

Arthroscopic anterior cruciate ligament (ACL) reconstruction with ligament advanced reinforcement system (LARS) had revealed good results with low complication and failure rate in series of studies. The specific candidates for ACL reconstruction with LARS are still unknown anyway. The purpose of this study is to evaluate the activity-related outcome in ACL reconstruction using LARS ligament.

METHODS

A total of 43 unilateral arthroscopic ACL reconstructions with LARS were collected and divided into two groups: group A (preinjury Tegner score ≥ 6, n = 20) and group B (preinjury Tegner score < 6, n = 23). We had analyzed the stability of knee and functional outcome with a minimum of 2-years follow up.

RESULTS

All patients were aware of improvement over the knee stability immediately after ACL reconstruction with LARS. The functional outcome of knee was improved in both groups by analysis with the Lysholm score and modified International Knee Documentation Committee (IKDC) score. The postoperative grading of the knee examination form of modified IKDC grade showed no statistical difference in both groups.

CONCLUSION

Arthroscopic ACL reconstruction with LARS was encouraged as an alternative option even in high sports demand patients.

Comparison of patellar tendon versus hamstrings autografts for anterior cruciate ligament reconstruction in Indian population: A randomised control trial study

Disruption of anterior cruciate ligament (ACL) is a common ligamentous injury of the knee. The best choice of graft for reconstruction remains undecided. This prospective, randomized clinical trial aimed to compare clinical results of bone-patellar tendon-bone (BPTB) grafts and four-strand semitendinosus-gracilis (QHT) grafts for ACL reconstruction over a 1-year follow-up interval in Indian population.

METHODS

42 consecutive patients with ACL injury were recruited, by pick and draw method and allotted into two groups with 21 patients in each group. Group A patients underwent arthroscopic ACL reconstruction using BPTB graft while QHT autograft was used for patients in Group B. All the patients underwent standard ipsilateral arthroscopic ACL reconstruction procedure using a single incision, antero-medial (AM) portal technique for BPTB or the QHT autograft by a same surgeon. Patients were followed up regularly for a minimum period of 1 year.

RESULTS

After one year, the Cincinnati score was 91 ± 4.117 in BPTB group and 89.29 ± 5.371 in QHT group (P = 0.282). There was no significant difference between the two groups in the mean scores with respect to pain, overall activity level and running in the Cincinnati score. None of the patients complained of the knee giving way. Similarly, at 1 year, the Lysholm score was 92.84 ± 2.630 and 90.55 ± 2.395 in the two groups respectively (P = 0.842). There were no episodes of locking or instability and there was no significant difference in the mean Lysholm scores regarding pain and squatting.

CONCLUSION

There was no significant functional difference between the two grafts in terms of Lysholm and the Cincinnati score, anterior knee laxity and altered sensation over proximal leg. The patients with QHT groups performed better than BPTB functionally at 6 month so early return to sport is possible even with QHT autograft.

Increased Postoperative Manual Knee Laxity at 2 Years Results in Inferior Long-term Subjective Outcome After Anterior Cruciate Ligament Reconstruction

BACKGROUND

Increased postoperative rotatory knee laxity after anterior cruciate ligament (ACL) reconstruction may be associated with an increased risk of osteoarthritis and inferior subjective outcome, although long-term studies are lacking. In terms of anteroposterior knee laxity, this association has not yet been established. Purpose/Hypothesis: The purpose was to investigate whether postoperative knee laxity is associated with inferior long-term outcome in patients who have undergone ACL reconstruction. The hypothesis was that increased laxity would cause an inferior long-term clinical and radiographic outcome.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

A total of 193 patients underwent ACL reconstruction and were examined at both 2 and 16 years postoperatively. At the 2-year follow-up, knee laxity was tested by use of the Lachman test, the anterior drawer test, the pivot-shift test, and the KT-1000 arthrometer. Outcome variables examined at the 16-year follow-up involved a radiographic assessment of osteoarthritis, patient-reported outcome measurements, and the single-legged hop test.

RESULTS

At the long-term follow-up, 147 (76%) patients were examined. The mean follow-up period for the included patients was 16.4 ± 1.2 years. A negative Lachman test at 2 years resulted in a superior International Knee Documentation Committee (IKDC) score (76.3 ± 19.4 vs 67.8 ± 19.3, P < .05) and Lysholm score (85.2 ± 11.9 vs 76.9 ± 17.8, P < .05) at the 16-year follow-up. Correspondingly, a negative anterior drawer test at 2 years was associated with a superior IKDC score (75.3 ± 18.7 vs 62.9 ± 20.2, P < .05) and Lysholm score (84.1 ± 12.1 vs 72.6 ± 20.2, P < .05) at 16 years. A negative pivot-shift test resulted in a superior IKDC score (74.5 ± 18.8 vs 46.9 ± 17.8, P < .05), a superior Lysholm score (83.3 ± 13.4 vs 58.9 ± 23.0, P < .05), and an increased level of activity (Tegner activity scale, median [range]: 4 [1-10] vs 3 [0-5], P < .05). Osteoarthritis was overrepresented in patients with positive manual knee laxity tests, but the difference was not statistically significant. The KT-1000 arthrometer result was not correlated with any outcome variables assessed in this study.

CONCLUSION

Increased manual anteroposterior and rotatory knee laxity 2 years after ACL reconstruction is associated with an inferior long-term subjective outcome.

Long-Term Results of Anterior Cruciate Ligament Reconstruction Using Hamstring Grafts and the Outside-In Technique: A Comparison Between 5- and 15-Year Follow-up

Background:

Increased femoral tunnel widening and weakness of the hamstring muscles postoperatively have been described as potential adverse events after anterior cruciate ligament (ACL) reconstruction (ACLR) with a hamstring graft. Meniscectomy and cartilage lesions are important factors for the development of degenerative osteoarthritis.

Purpose:

To compare 15-year follow-up data with 5-year follow-up data from the same cohort of patients after ACLR with a hamstring autograft using an outside-in technique.

Study Design:

Case series; Level of evidence, 4.

Methods:

A total of 72 patients who underwent anatomic ACLR with a quadruple hamstring graft and an outside-in technique were selected for this prospective study. Patients were reviewed at a minimum follow-up of 15 years. Results were compared with the same series of patients previously reviewed at 5 years after surgery. Lysholm, International Knee Documentation Committee (IKDC), and Tegner scores as well as KT-1000 arthrometer measurements were obtained at final follow-up. Comparative weightbearing radiographs were obtained and analyzed according to the Fairbank, Kellgren-Lawrence, and IKDC classifications and used for the tunnel evaluation.

Results:

No significant difference was detected on the subjective evaluation. Objectively, patients categorized as A or B according to the IKDC score were not significantly different at 5 and 15 years (P < .01). A KT-1000 arthrometer side-to-side manual maximum difference >5 mm, a pivot shift >2+, any giving-way episode, and ACL revision surgery were considered as failures, and these were noted in 6 patients at 5 years and 6 patients at 15 years. The radiological evaluation at 15 years showed a higher rate of osteoarthritis in 2 of 3 radiological scales used in the study compared with results at 5-year follow-up (P < .01). At 15-year follow-up, there was a statistically significant reduction in the mean tibial tunnel diameter (P < .01).

Conclusion:

Endoscopic single-bundle ACLR using hamstring grafts and an outside-in technique demonstrated good results at 15-year follow-up in terms of subjective, objective, and radiographic evaluations. As compared with 5-year follow-up, clinical results remained stable both subjectively and objectively. However, a progression of osteoarthritis changes was observed, especially in patients in whom meniscectomy had been performed.

High Rates of Osteoarthritis Develop After Anterior Cruciate Ligament Surgery: An Analysis of 4108 Patients

BACKGROUND

Posttraumatic osteoarthritis (PTOA) after anterior cruciate ligament (ACL) reconstruction ultimately translates into a large economic effect on the health care system owing to the young ages of this population. Purpose/Hypothesis: The purposes were to perform a meta-analysis to determine the prevalence of osteoarthritis after an ACL reconstruction, examining the effects of length of time after surgery, preoperative time interval from injury to surgery, and patient age at the time of surgery. It was hypothesized that the prevalence of PTOA increased with time from surgery and that increased time from injury to surgery and age were also risk factors for the development of PTOA.

STUDY DESIGN

Meta-analysis.

METHODS

A meta-analysis of the prevalence of radiographic PTOA after ACL reconstruction was performed of studies with a minimum of 5 years' follow-up, with a level of evidence of 1, 2, or 3. The presence of osteoarthritis was defined according to knee radiographs evaluated with classification based on Kellgren and Lawrence, Ahlbäck, International Knee Documentation Committee, or the Osteoarthritis Research Society International. Metaregression models quantified the relationship between radiographic PTOA prevalence and the mean time from injury to surgery, mean patient age at time of surgery, and mean postoperative follow-up time.

RESULTS

Thirty-eight studies (4108 patients) were included. Longer postsurgical follow-up time was significantly positively associated with a higher proportion of PTOA development. The model-estimated proportion of PTOA (95% CI) at 5, 10, and 20 years after surgery was 11.3% (6.4%-19.1%), 20.6% (14.9%-27.7%), and 51.6% (29.1%-73.5%), respectively. Increased chronicity of the ACL tear before surgery and increased patient age were also associated with a higher likelihood of PTOA development.

CONCLUSION

The prevalence of osteoarthritis after an ACL reconstruction significantly increased with time. Longer chronicity of ACL tear and older age at the time of surgery were significantly positively correlated with the development of osteoarthritis. A timely referral and treatment of symptomatic patients are vital to diminish the occurrence of PTOA.

Short-Term Contact Kinematic Changes and Longer-Term Biochemical Changes in the Cartilage After ACL Reconstruction: A Pilot Study

Investigation of the development of cartilage degeneration after ACL reconstruction is important for improving current surgical treatment of ACL injuries to prevent long-term knee joint degeneration. This pilot study examined the relationship between the changes in weight-bearing knee contact kinematics 6 months after ACL reconstruction and the biochemical composition changes in the knee cartilage measured using T2 relaxation values 3 years after the surgery in seven patients. The analysis indicated that the change of the knee contact kinematics in short-term after ACL reconstruction is associated with an increase of T2 values of the cartilage in longer follow up times. The data of this study could provide preliminary data to power future studies that use prospective, longitudinal research and large patient populations to establish prognostic biomechanical markers for determination of long-term cartilage degeneration after ACL reconstruction.

The Long-Term Outcome After Early and Late Anterior Cruciate Ligament Reconstruction

PURPOSE

To compare long-term clinical and radiographic outcomes in patients undergoing either early (group A) or late (group B) surgery after anterior cruciate ligament (ACL) injury.

METHODS

ACL reconstruction using hamstring tendon autografts was performed in 30 patients in group A (median age, 23 years; range, 17-49 years) and 31 patients in group B (median age, 27 years; range, 17-38 years). The patients in group A were operated on within 5 months (median, 3 months; range, 2-5 months) of injury, whereas those in group B were operated on more than 24 months (median, 30 months; range, 24-48 months) after injury. The follow-up period was 10 years (median, 117 months [range, 77-222 months] in group A and 129 months [range, 77-206 months] in group B; P = .44). Multiple objective clinical evaluation tests and patient-reported outcome measures were obtained preoperatively and at follow-up. At follow-up, radiographic assessments of knee osteoarthritis (OA) bilaterally were performed.

RESULTS

The frequency of meniscectomy at the index operation was significantly lower in group A (20%) than in group B (52%) (P = .01). There were no significant differences between the groups in terms of Tegner and Lysholm scores and laxity tests both preoperatively and at follow-up. Both groups improved over time in terms of Tegner and Lysholm scores (P < .05). At follow-up, significantly more medial-compartment OA in the index knee was found in group B than in group A (P = .037) according to the Ahlbäck classification system. The index knee showed significantly more OA than the contralateral knee in both groups (P < .01).

CONCLUSIONS

Patients who underwent early ACL reconstruction required significantly fewer meniscectomies at the index operation than patients who underwent late reconstruction and showed significantly less OA on the medial side of the knee 10 years after reconstruction. However, no significant differences were found between the groups in terms of clinical assessments.

LEVEL OF EVIDENCE

Level III, retrospective comparative study.

Biological and Biomechanical Evaluation of Autologous Tendon Combined with Ligament Advanced Reinforcement System Artificial Ligament in a Rabbit Model of Anterior Cruciate Ligament Reconstruction

OBJECTIVE

To compare the biomechanical and histological changes in a rabbit model after reconstructing the anterior cruciate ligament (ACL) with solely autologous tendon and with autologous tendon combined with the ligament advanced reinforcement system (LARS) artificial ligament.

METHODS

Anterior cruciate ligament reconstruction was performed in 72 knees from 36 healthy New Zealand white rabbits (bodyweight, 2500-3000 g). The Achilles tendons were harvested bilaterally. The left ACL were reconstructed solely with autografts (autologous tendon group), while the right ACL were reconstructed with autografts combined with LARS ligaments (combined ligaments group). The gross observation, histological determination, and the tension failure loads in both groups were evaluated at 12 weeks (n = 18) and 24 weeks (n = 18) postoperatively.

RESULTS

Gross examination of the knee joints showed that all combined ligaments were obviously covered by a connective tissue layer at 12 weeks, and were completely covered at 24 weeks. Fibrous tissue ingrowth was observed between fascicles and individual fibers in the bone-artificial ligament interface at both time points; this fibrovascular tissue layer localized at the bone-artificial ligament interface tended to be denser in specimens obtained at 24 weeks compared with those obtained at 12 weeks. The tension failure loads of the knees were similar in the autologous tendon group and the combined ligaments group at 12 weeks (144.15 ± 3.92 N vs. 140.88 ± 2.75 N; P > 0.05), and at 24 weeks (184.15 ± 1.96 N vs. 180.88 ± 3.21 N; P > 0.05).

CONCLUSION

Reconstructing the ACL in rabbits using autologous tendon combined with the LARS artificial ligament results in satisfactory biointegration, with no obvious immunological rejection between the autologous tendon and the artificial ligament, and is, therefore, a promising ACL reconstruction method.

No risk of arthrofibrosis after acute anterior cruciate ligament reconstruction

PURPOSE

To compare acute ACL reconstruction (ACLR) within 8 days of injury with delayed reconstruction after normalized range of motion (ROM), 6-10 weeks after injury. It was hypothesized that acute ACL reconstruction with modern techniques is safe and can be beneficial in terms of patient-reported outcomes and range of motion.

METHODS

Sample size calculation indicated 64 patients would be required to find a 5° difference in ROM at 3 months. Seventy patients with high recreational activity level, Tegner level 6 or more, were randomized to acute (within 8 days) or delayed (6-10 weeks) ACLR between 2006 and 2013. During the first 3 months following surgery patients were contacted weekly by SMS and asked 'How is your knee functioning?', with answers given on a Visual-Analog Scale (0-10). ROM was assessed after 3 months by the rehab physiotherapist. Patient-reported outcomes, objective IKDC and manual stability measurements were collected by an independent physiotherapist not involved in the rehab at the 6-month follow-up.

RESULTS

At 3-month follow-up, 91% of the patients were assessed with no significant differences in flexion, extension or total ROM demonstrated between groups. At the 6-month follow-up, the acute group had significantly less muscle atrophy of the thigh muscle compared to the contralateral leg. Furthermore, a significantly higher proportion of patients in the acute group passed or were close to passing the one leg hop test (47 versus 21%, p = 0.009). No difference was found between the groups in the other clinical assessments. Additionally, no significant difference between the groups was found in terms of associated injuries.

CONCLUSION

Acute ACLR within 8 days of injury does not appear to adversely affect ROM or result in increased stiffness in the knee joint when compared to delayed surgery.

LEVEL OF EVIDENCE

II.

Radiographic Tibial Tunnel Assessment After Anterior Cruciate Ligament Reconstruction Using Hamstring Tendon Autografts and Biocomposite Screws: A Prospective Study With 5-Year Follow-Up

PURPOSE

To radiographically assess the tibial tunnel up to 5 years after anterior cruciate ligament (ACL) reconstruction using hamstring tendon autografts and biocomposite interference screws.

METHODS

Fifty-one patients underwent anatomic single-bundle ACL reconstruction with metal interference screws in the femur and biocomposite interference screws in the tibia. Standardized digital radiographs with weight-bearing anteroposterior and lateral views of the index knee were taken in the early postoperative period and at 2 and 5 years postoperatively. Of 51 patients, 40 (78%) underwent radiographic assessment on all 3 occasions. Subjective and objective clinical assessments were obtained preoperatively and at the 5-year follow-up.

RESULTS

The mean follow-up period was 65 months (±3.9 months), with a minimum of 59 months. The width of the tibial tunnel on the anteroposterior view was 9.4 mm (±1.4 mm) in the early postoperative period and 9.2 mm (±1.5 mm) at 5 years (P = .64). The corresponding widths on the lateral view were 9.6 mm (±1.5 mm) in the early postoperative period and 9.0 mm (±1.4 mm) at 5 years (P = .014). In 33 of 40 patients (83%) the width of the tibial tunnel had decreased on 1 or both views at 5 years compared with the early postoperative period. The study group had improved significantly at the 5-year follow-up compared with the preoperative assessments in terms of the KT-1000 arthrometer laxity tests (MEDmetric, San Diego, CA), pivot-shift test, Tegner activity scale, and Lysholm knee score (P < .001). No correlations were found between the tunnel widths and the KT-1000 assessment.

CONCLUSIONS

In 83% of patients, the width of the tibial tunnel had decreased on 1 or both radiographic views at 5 years compared with the early postoperative period after ACL reconstruction using biocomposite interference screws.

LEVEL OF EVIDENCE

Level II, prospective study.

Quantitative knee cartilage measurement at MR imaging of patients with anterior cruciate ligament tear

In previous studies, numerous approaches were proposed that assess knee cartilage volume quantitatively using 3D magnetic resonance (MR) imaging. However, the clinical use of these approaches is limited because 3D MR is prone to metal artifacts in postoperative cases. Our purpose in this study was to validate a method for knee cartilage volume quantification using conventional MR imaging in patients who underwent anterior cruciate ligament (ACL) reconstruction surgery. The study included 16 patients who underwent MR imaging before and 1 year after ACL reconstruction surgery. Knee cartilage volumes were measured by our computer-based method with the use of T1-weighted sagittal images. We classified the cartilage into eight regions and made comparisons between preoperative and postoperative cartilage volumes in each region. There was a significant difference between preoperative and postoperative cartilage volumes with regard to medial posterior weight-bearing, medial posterior, lateral posterior weight-bearing, and lateral posterior portions (p = 0.006, 0.023, 0.017 and 0.002, respectively). These results were consistent with the previous studies showing that knee cartilage loss occurs frequently in these portions due to an anterior subluxation of the tibia accompanied by ACL tear. With our method, knee cartilage volumes could be measured quantitatively with conventional MR imaging in patients who underwent ACL reconstruction surgery.

Knee Osteoarthritis after Reconstruction of Isolated Anterior Cruciate Ligament Injuries: A Systematic Literature Review

Purpose  The aim of this review was to analyze the current literature on osteoarthritic evolution of knees without any combined meniscal or ligament lesions undergoing anterior cruciate ligament (ACL) reconstruction.

Methods  A PubMed/MEDLINE research was performed using the following keywords: “Anterior Cruciate Ligament Reconstruction” [Mesh] AND “Osteoarthritis, Knee” [Mesh]. Only English language literature and articles published after 2005 were included. Studies including concomitant meniscal tears, posterior cruciate or collateral ligament injuries, previous surgery in the affected knees, infections, osteochondral defects, loose bodies, synovial plica syndrome, and posteromedial or posterolateral corner injuries were not considered in this review.

Results  Twelve studies were selected. These papers included 892 patients (mean age at the time of surgery was 22.3 years), with an average follow-up of 11 years. Imaging at follow-up was obtained with standard radiographs in nine studies, magnetic resonance imaging (MRI) in one study, and both X-rays and MRI in two studies. Eight studies reported osteoarthritic evolution, with different prevalence.

Conclusion  Only few high-quality studies focused on these specific patients have been published. When reconstructed, isolated ACL-deficient knees have a low risk of osteoarthritic evolution, but mild signs of joint degeneration are reported by the current literature.

Level of Evidence  Level IV, systematic review of level I to level IV studies.

Comparison of Anteromedial and Transtibial ACL Reconstruction Using Expandable Fixation

The influence of anatomical or nonanatomical femoral tunnel position on tunnel widening and clinical outcomes in patients undergoing anterior cruciate ligament (ACL) reconstruction is not fully understood. This retrospective study examined the influence of tunnel width and placement on anterior knee stability and clinical outcomes after ACL reconstruction using the AperFix System (Cayenne Medical Inc, Scottsdale, Arizona), a direct expandable fixation technique with autologous hamstring grafts. The records of 80 patients (79 men and 1 woman) who underwent ACL reconstruction were evaluated. In 38 patients, anatomical femoral tunnel placement was performed via an accessory medial portal (anteromedial group); in the remaining 42 patients, the femoral tunnel was positioned nonanatomically using a transtibial technique (transtibial group). Mean follow-up was 40.7 months (range, 27-60 months). Postoperative knee kinetics were measured, and clinical outcomes were assessed using International Knee Documentation Committee, Lysholm, and Tegner scores. Femoral tunnel widening was measured by comparing postoperative radiographs with final follow-up radiographs. Femoral tunnel width was significantly greater (P<.001) and anterior knee translation was significantly higher (P=.01) in the transtibial group. Lysholm and Tegner scores were not significantly different (P>.05) between the 2 groups. These findings suggest that femoral tunnel widening is associated with increased anterior joint laxity when a direct fixation technique is used for ACL reconstruction, particularly in nonanatomically positioned femoral tunnels. Anatomical femoral tunnel placement provides better anterior stability and less tunnel widening than transtibial tunnel placement; however, these benefits did not produce a detectable advantage in clinical outcomes measures. [Orthopedics. 2017; 40(3):e532-e537.].

The prevalence of radiographic and MRI-defined patellofemoral osteoarthritis and structural pathology: a systematic review and meta-analysis

BACKGROUND

Patellofemoral osteoarthritis (PF OA) is more prevalent than previously thought and contributes to patient's suffering from knee OA. Synthesis of prevalence data can provide estimates of the burden of PF OA.

OBJECTIVE

This study aims to conduct a systematic review and meta-analysis on the prevalence of PF OA and structural damage based on radiography and MRI studies in different populations.

METHODS

We searched six electronic databases and reference lists of relevant cross-sectional and observational studies reporting the prevalence of PF OA. Two independent reviewers appraised methodological quality. Where possible, data were pooled using the following categories: radiography and MRI studies.

RESULTS

Eighty-five studies that reported the prevalence of patellofemoral OA and structural damage were included in this systematic review. Meta-analysis revealed a high prevalence of radiographic PF OA in knee pain or symptomatic knee OA (43%), radiographic knee OA or at risk of developing OA (48%) and radiographic and symptomatic knee OA (57%) cohorts. The MRI-defined structural PF damage in knee pain or symptomatic population was 32% and 52% based on bone marrow lesion and cartilage defect, respectively.

CONCLUSION

One half of people with knee pain or radiographic OA have patellofemoral involvement. Prevalence of MRI findings was high in symptomatic and asymptomatic population. These pooled data and the variability found can provide evidence for future research addressing risk factors and treatments for PF OA.

TRIAL REGISTRATION NUMBER

PROSPERO systematic review protocol (CRD42016035649).

Rehabilitation Principles of the Anterior Cruciate Ligament Reconstructed Knee: Twelve Steps for Successful Progression and Return to Play

The rehabilitation process begins immediately after injury to the anterior cruciate ligament (ACL). The goal of preoperative rehabilitation is to prepare the patient for surgery. Current rehabilitation programs focus on strengthening exercises and proprioceptive and neuromuscular control drills to provide a neurologic stimulus. It is also important to address preexisting factors, especially for the female athlete, that may predispose to future injury, such as hip and hamstring weakness. Our goal in the rehabilitation program is to restore full, unrestricted function and to assist the patient to return to 100% of the preinjury level while achieving excellent long-term outcomes.

Arthroscopic anatomic double-bundle ACL reconstruction using irradiated versus non-irradiated hamstring tendon allograft

PURPOSE

To analyse the clinical outcome of anatomic double-bundle anterior cruciate ligament (ACL) reconstruction with irradiated versus non-irradiated hamstring allograft.

METHODS

One hundred and twelve patients who met the inclusion and exclusion criteria of the study were prospectively randomized consecutively into irradiated hamstring tendon allograft (Ir-Allo) group and non-irradiated allograft (Non-ir-Allo) group. All surgeries were done by the same senior surgeon with double-bundle reconstruction technique. Before surgery and at follow-up points, patients were evaluated by the same observer according to clinical evaluations.

RESULTS

Eighty-three patients (Non-ir-Allo, 44; Ir-Allo, 39) fulfilled complete follow-up and got full clinical evaluations. The mean follow-up period was 5.7 years (ranging from 5.0 to 6.5 years). At the final follow-up, significant differences were found when comparing the results of the two groups according to Lachman test, ADT, pivot shift test and KT-2000 arthrometer testing (P < 0.05). According to KT-2000, 86.4 % of patients in the Non-ir-Auto group and 35.9 % in the Ir-Allo group had a side-to-side difference of <3 mm. According to the overall IKDC, functional, subjective evaluations and activity level testing, no significant differences were found between the two groups. Regarding the arthritic progression, there was significant difference between the two groups (Ir-Allo group: 30.8 %, Non-ir-Allo group: 11.4 %, P < 0.05).

CONCLUSION

A significant increase in anterior and rotational laxity in patients of the Ir-Allo group was found according to evaluations. No significant differences in activity level and functional scores were found between the two groups. We do not advocate the irradiated hamstring tendon allograft for ACL reconstruction.

LEVEL OF EVIDENCE

I.

History of previous knee surgery does not affect the clinical outcomes of primary total knee arthroplasty in an Asian population

BACKGROUND

Patients with a history of previous knee surgeries, such as anterior cruciate ligament reconstruction (ACLR) and high tibial osteotomy (HTO), often have a higher likelihood of requiring a subsequent total knee arthroplasty (TKA). However, there is relatively limited data, especially in the Asian population, on how previous knee surgery could affect the clinical outcomes of TKA. Therefore, this study aims to evaluate the impact of previous knee surgeries on the clinical outcomes of future TKA.

METHODS

We reviewed the prospectively-collected data of 303 patients who underwent TKA by a single surgeon from a total joint registry of a tertiary hospital over a period of 5 years. Those with a history of previous knee surgery were identified. The SF-36 Health Survey, Oxford Knee Score (OKS) and Knee Society Score (KSS) were used to evaluate clinical outcomes pre-operatively, at 6 months and 2 years.

RESULTS

Previous knee surgery did not have a significant impact on the patients' pre-operative baseline clinical scores and body mass index (BMI). Patients with a history of knee surgery undergo TKA at a significantly younger age (mean of 6.6 years younger). On follow-up, patients with a history of knee surgery have similar post-operative outcome scores as those without previous knee surgery. Also, a high proportion of these patients are satisfied with their post-operative results and feel that their expectations have been met.

CONCLUSIONS

Patients with previous knee surgery had TKA at a significantly younger age than those without. But these patients have similar clinical and quality of life outcomes after TKA. In addition, a high proportion of these patients are satisfied with the results of surgery and feel that their expectations of TKA are met. This is important for clinicians when counselling patients pre-operatively.

A Randomized Controlled Trial With Mean 16-Year Follow-up Comparing Hamstring and Patellar Tendon Autografts in Anterior Cruciate Ligament Reconstruction

BACKGROUND

There is no consensus in the current literature on which surgical options render the best long-term results after anterior cruciate ligament (ACL) reconstruction in terms of clinical outcomes and the development of radiographic osteoarthritis (OA).

PURPOSE

To investigate the long-term clinical and radiographic results after ACL reconstruction using either a patellar tendon (PT) autograft or a hamstring tendon (HT) autograft.

STUDY DESIGN

Randomized controlled trial; Level of evidence, 2.

METHODS

This multicenter study was based on 2 previous randomized cohorts consisting of 193 patients who underwent unilateral primary ACL reconstruction using either a PT autograft or an HT autograft. The index surgical procedure was performed between September 1995 and January 2000. Clinical assessments, including knee laxity measurements, functional outcomes, patient-reported outcomes, and bilateral standing radiographs, were performed at the final follow-up examination.

RESULTS

At the long-term follow-up, 147 (76%) patients were examined: 61 in the PT group and 86 in the HT group. The mean (±SD) follow-up time was 191.9 ±15.1 months for the HT group and 202.6 ± 10.4 months for the PT group. Knee laxity measurements revealed significantly more patients with a normal pivot-shift test finding in the HT group compared with the PT group (71% vs 51%, respectively; P = .048); however, no significant differences were found in terms of the manual Lachman test or the KT-1000 arthrometer manual maximum test. The patients in the PT group had significantly more difficulty knee walking (P = .049). There were no significant differences between the study groups in terms of patient-reported outcomes or range of motion in the reconstructed knee. In both groups, significantly more signs of radiographic OA were found in the reconstructed knee than in the contralateral healthy knee. However, there were no significant differences between the groups in terms of radiographic OA.

CONCLUSION

Only minor and mostly insignificant differences were found between the PT and HT autograft groups in this long-term randomized controlled trial. In both groups, significantly more signs of radiographic OA were found in the reconstructed knee than in the contralateral knee.

Comparison of Anatomic Double- and Single-Bundle Techniques for Anterior Cruciate Ligament Reconstruction Using Hamstring Tendon Autografts: A Prospective Randomized Study With 5-Year Clinical and Radiographic Follow-up

BACKGROUND

The aim of this prospective randomized study was to compare the outcomes of the anatomic double-bundle (DB) and anatomic single-bundle (SB) techniques 5 years after anterior cruciate ligament (ACL) reconstruction. Since more effective restoration of rotational laxity is considered the main advantage of the DB technique, the pivot-shift test was the primary outcome variable of the study.

HYPOTHESIS

Double-bundle ACL reconstruction will result in a better outcome in terms of the pivot-shift test.

STUDY DESIGN

Randomized controlled trial; Level of evidence, 1.

METHODS

A total of 105 patients (33 women, 72 men; median age, 27 years; range, 18-52 years) were randomized and underwent ACL reconstruction (DB group, n = 53; SB group, n = 52). All reconstructions were performed anatomically by identifying the ACL footprints, using the anteromedial portal for the femoral tunnel drilling, and utilizing interference screw for tibial and femoral fixation. A single blinded observer examined the patients preoperatively and at follow-up (median, 64 months; range, 55-75 months). Multiple subjective and objective clinical evaluation tests and radiographic assessments of osteoarthritis (OA) were performed using the Ahlbäck, Kellgren-Lawrence, and Fairbank grading systems at 6 weeks postoperatively and at the final follow-up evaluation.

RESULTS

Preoperatively, no differences were found between the study groups, apart from the preinjury Tegner activity level, which was lower in the DB group (SB: mean, 7.8 [range, 3-9]; DB: mean, 7.3 [range, 0-9]; P = .02). Eighty-seven patients (83%) were available for examination at the 5-year follow-up. Statistical differences could not be found between the groups in terms of the pivot-shift test, KT-1000 arthrometer laxity measurements, manual Lachman test, single-legged-hop test, square-hop test, range of motion, Lysholm knee scoring scale, Tegner activity scale, or Knee injury and Osteoarthritis Outcome Score. Correspondingly, no differences were found between the groups regarding the presence of OA at follow-up. However, a significant increase of OA was found within the DB group at the 5-year follow-up. Both groups improved at follow-up compared with the preoperative assessment in terms of the laxity tests, hop tests, and scoring scales.

CONCLUSION

At the 5-year follow-up of an unselected group of patients, anatomic DB reconstruction was not superior to anatomic SB reconstruction in terms of the pivot-shift test.

American Society of Biomechanics Clinical Biomechanics Award 2015: MRI assessments of cartilage mechanics, morphology and composition following reconstruction of the anterior cruciate ligament

BACKGROUND

The pathogenesis of osteoarthritis following anterior cruciate ligament (ACL) reconstruction is currently unknown. The study purpose was to leverage recent advances in quantitative and dynamic MRI to test the hypothesis that abnormal joint mechanics within four years of reconstruction is accompanied by evidence of early compositional changes in cartilage.

METHODS

Static MR imaging was performed bilaterally on eleven subjects with an ACL reconstruction (1-4years post-surgery) and on twelve healthy subjects to obtain tibial cartilage thickness maps. Quantitative imaging (mcDESPOT) was performed unilaterally on all subjects to assess the fraction of bound water in the tibial plateau cartilage. Finally, volumetric dynamic imaging was performed to assess cartilage contact patterns during an active knee flexion-extension task. A repeated-measures ANOVA was used to test for the effects of surgical reconstruction and location on cartilage thickness, bound water fractions, and contact across the medial and lateral tibia plateaus.

FINDINGS

No significant differences in cartilage thickness were found between groups. However, there was a significant reduction in the fraction of water bound by proteoglycan in the ACL reconstructed knees, most notably along the anterior portion of the medial plateau and the weight-bearing lateral plateau. During movement, reconstructed knees exhibited greater contact along the medial spine in the medial plateau and along the posterior aspect of the lateral plateau, when compared with their healthy contralateral knees and healthy controls.

INTERPRETATION

This study provides evidence that abnormal mechanics in anterior cruciate ligament reconstructed knees are present coincidently with early biomarkers of cartilage degeneration.

Anterior Cruciate Ligament: Structure, Injuries and Regenerative Treatments

Anterior cruciate ligament (ACL) is one of the most vulnerable ligaments of the knee. ACL impairment results in episodic instability, chondral and meniscal injury and early osteoarthritis. The poor self-healing capacity of ACL makes surgical treatment inevitable. Current ACL reconstructions include a substitution of torn ACL via biological grafts such as autograft, allograft. This review provides an insight of ACL structure, orientation and properties followed by comparing the performance of various constructs that have been used for ACL replacement. New approaches, undertaken to induce ACL regeneration and fabricate biomimetic scaffolds, are also discussed.

An In Vitro Robotic Assessment of the Anterolateral Ligament, Part 1: Secondary Role of the Anterolateral Ligament in the Setting of an Anterior Cruciate Ligament Injury

BACKGROUND

Recent investigations have described the structural and functional behavior of the anterolateral ligament (ALL) of the knee through pull-apart and isolated sectioning studies. However, the secondary stabilizing role of the ALL in the setting of a complete anterior cruciate ligament (ACL) tear has not been fully defined for common simulated clinical examinations, such as the pivot-shift, anterior drawer, and internal rotation tests.

HYPOTHESIS

Combined sectioning of the ALL and ACL would lead to increased internal rotation and increased axial plane translation during a pivot-shift test when compared with isolated sectioning of the ACL.

STUDY DESIGN

Controlled laboratory study.

METHODS

Ten fresh-frozen human cadaveric knees were subjected to a simulated pivot-shift test with coupled 10-N·m valgus and 5-N·m internal rotation torques from 0° to 60° of knee flexion and a 5-N·m internal rotation torque and an 88-N anterior tibial load, both from 0° to 120° of knee flexion via a 6 degrees of freedom robotic system. Kinematic changes were measured and compared with the intact state for isolated sectioning of the ACL and combined sectioning of the ACL and ALL.

RESULTS

Combined sectioning of the ACL and ALL resulted in a significant increase in axial plane tibial translation during a simulated pivot shift at 0°, 15°, 30°, and 60° of knee flexion and a significant increase in internal rotation at 0°, 15°, 30°, 45°, 60°, 75°, 90°, 105°, and 120° when compared with the intact and ACL-deficient states. Based on the model results, ALL sectioning resulted in an additional 2.1 mm (95% CI, 1.4-2.9 mm; P < .001) of axial plane translation during the pivot shift when compared with ACL-only sectioning, when pooling evidence over all flexion angles. Likewise, when subjected to IR torque, the ACL+ALL-deficient state resulted in an additional 3.2° of internal rotation (95% CI, 2.4°-4.1°; P < .001) versus the intact state, and the additional sectioning of the ALL increased internal rotation by 2.7° (95% CI, 1.8°-3.6°; P < .001) versus the ACL-deficient state.

CONCLUSION

The results of this study confirm the ALL as an important lateral knee structure that provides rotatory stability to the knee. Specifically, the ALL was a significant secondary stabilizer throughout flexion during an applied internal rotation torque and simulated pivot-shift test in the context of an ACL-deficient knee.

CLINICAL RELEVANCE

Residual internal rotation and a positive pivot shift after ACL reconstruction may be attributed to ALL injury. For these patients, surgical treatment of an ALL tear may be considered.

Factors associated with a more rapid recovery after anterior cruciate ligament reconstruction using multivariate analysis

BACKGROUND

In the past, several studies investigated factors that are prognostic or associated with outcome after anterior cruciate ligament (ACL) reconstruction. A recent review showed that only limited evidence is available for most studied factors, and that insufficient analysis methods were used commonly. Therefore, the aim of this study was to add more weight to the existing evidence, about factors that are associated with a more rapid outcome after ACL reconstruction. The second aim was to use multivariate analysis to study the possible factors independently.

METHODS

A cohort study was conducted with a follow-up of six months. Before surgery, patient variables were scored. Surgical variables were scored during arthroscopic ACL reconstructions with a single-bundle technique and hamstring autograft. The Lysholm score and subscales of the Knee Injury Osteoarthritis Outcome Score (KOOS) were assessed six months post surgery. A multiple analysis of variance (ANOVA) model was used to identify prognostic factors for outcome.

RESULTS

In total, 118 patients were included. Patients, aged ≤30years, with a subjective knee score ≥ six, with normal flexion range of motion (ROM) of the knee, with flexion and extension strength deficit of ≤20%, and those with no previous knee surgery in the same knee at baseline scored significantly higher on outcome after multivariate analysis. No significant effect of surgical factors could be found.

CONCLUSION

Younger age, higher subjective knee score, normal knee flexion, normal knee flexion and extension strength, and no previous knee surgery in the patients' history at baseline are associated with a more rapid recovery after ACL reconstruction.

LEVEL OF EVIDENCE

Level III, prognostic study.

RISKS AND CONSEQUENCES OF USING THE TRANSPORTAL TECHNIQUE IN RECONSTRUCTING THE ANTERIOR CRUCIATE LIGAMENT: RELATIONSHIPS BETWEEN THE FEMORAL TUNNEL, LATERAL SUPERIOR GENICULAR ARTERY AND LATERAL EPICONDYLE OF THE FEMORAL CONDYLE

Objective: Define a security zone to avoid possibles vascular and ligamentar complications during anterior cruciate ligament reconstruction. Methods: Arthroscopic reconstruction using the transtibial and transportal technique in cadaver knees was performed followed by dissection and measurement of the distance between the femoral tunnel and the proximal attachment of the lateral collateral ligament and the femoral tunnel and the lateral superior genicular artery. Results: The measure of the analysed distances show us an aproximation between the major branch of the lateral superior genicular artery and the femoral insertion of the colateral lateral ligament and the femoral tunnel during the transportal technique. Conclusion: We realize that the use of technical ship it to arthroscopic ACL reconstruction has a higher probability of injury to the lateral geniculate artery and insertion of the lateral collateral ligament, promoting post-surgical complications such as instability of the knee, osteonecrosis of the femoral condyle and ligamentização graft.

Anterior Cruciate Ligament Injury Prevention and Rehabilitation: Let's Get It Right

Anterior cruciate ligament (ACL) injuries are among the most common and functionally disabling conditions in orthopaedics and sports medicine. As professionals, we need to do a better job of screening individuals to determine who is at greatest risk of sustaining an ACL injury, as well as implementing injury prevention programs. We also need to do a better job with programs that return individuals to their preinjury activity levels, including implementing thorough functional testing to determine if a patient is ready to return to sports or strenuous activities post-ACLR.

Kinematic Analysis of Five Different Anterior Cruciate Ligament Reconstruction Techniques

Several anatomical anterior cruciate ligament (ACL) reconstruction techniques have been proposed to restore normal joint kinematics. However, the relative superiorities of these techniques with one another and traditional single-bundle reconstructions are unclear. Kinematic responses of five previously reported reconstruction techniques (single-bundle reconstruction using a bone-patellar tendon-bone graft [SBR-BPTB], single-bundle reconstruction using a hamstring tendon graft [SBR-HST], single-tunnel double-bundle reconstruction using a hamstring tendon graft [STDBR-HST], anatomical single-tunnel reconstruction using a hamstring tendon graft [ASTR-HST], and a double-tunnel double-bundle reconstruction using a hamstring tendon graft [DBR-HST]) were systematically analyzed. The knee kinematics were determined under anterior tibial load (134 N) and simulated quadriceps load (400 N) at 0°, 15°, 30°, 60°, and 90° of flexion using a robotic testing system. Anterior joint stability under anterior tibial load was qualified as normal for ASTR-HST and DBR-HST and nearly normal for SBR-BPTB, SBR-HST, and STDBR-HST as per the International Knee Documentation Committee knee examination form categorization. The analysis of this study also demonstrated that SBR-BPTB, STDBR-HST, ASTR-HST, and DBR-HST restored the anterior joint stability to normal condition while the SBR-HST resulted in a nearly normal anterior joint stability under the action of simulated quadriceps load. The medial-lateral translations were restored to normal level by all the reconstructions. The internal tibial rotations under the simulated muscle load were over-constrained by all the reconstruction techniques, and more so by the DBR-HST. All five ACL reconstruction techniques could provide either normal or nearly normal anterior joint stability; however, the techniques over-constrained internal tibial rotation under the simulated quadriceps load.

ACL injury and posttraumatic osteoarthritis

Continued development and validation of quantitative imaging and biochemical assessment techniques are critical research priorities to lead to improved diagnosis and treatment of PTOA. There is also a compelling need to advance understanding of how mechanical joint injuries lead to joint degeneration, and to define the roles of acute joint damage and post–joint injury incongruity and instability as etiologic factors leading to development of OA.22 As OA occurs more frequently in the military population and ACL tears are endemic to the military, it is essential that the military become more active in funding research and seeking novel research cohorts to help solve some of the most fundamental problems in PTOA. The military population, while deeply affected by PTOA, may also prove to be pivotal in determining improved diagnostic techniques and treatment interventions to help minimize the long-term effects of this disease.

Factors associated with excellent 6-month functional and isokinetic test results following ACL reconstruction

PURPOSE

To identify patient concomitant injury and surgical characteristics associated with 6-month excellent functional and isokinetic testing results following anterior cruciate ligament (ACL) reconstruction.

METHODS

Patients that underwent ACL reconstruction by a single surgeon had isokinetic and functional testing performed with excellent 6-month outcome defined as greater than 85 % in isokinetic strength and 90 % in functional tests (excellent 6-month group vs. delayed 6-month group). Patient concomitant injury and surgical factors were then analysed in univariate and multivariate statistical models to assess which characteristics predicted the excellent 6-month group.

RESULTS

The 224 patients included 93 males and 131 females, with median age of 22 (range 12-59) years, body mass index (BMI) of 25.4 (range 17-44), and median Tegner activity score of 6 (range 2-10). Fifty-two patients (23 %) were included in the excellent 6-month group, while 172 patients (77 %) were in the delayed 6-month group. In univariate analysis, favourable factors with the excellent 6-month outcome group were younger age (24 vs. 27; p = 0.01), lower BMI (24.5 vs. 26.2; p = 0.03), and minimal articular cartilage damage (71 vs. 56 %; p = 0.048). In multivariate analysis, a negative effect was observed for patients older than 30 years that had ACL reconstruction with autograft (p = 0.0004).

CONCLUSION

Factors significantly associated with excellent 6-month functional and isokinetic test results following ACL reconstruction included younger age, lower BMI, and minimal cartilage degeneration. The use of allograft was associated with improved functional and strength testing after ACL reconstruction in patients over 30 years of age.

LEVEL OF EVIDENCE

Prognostic/therapeutic study, Level III.

Quantitative MRI T2 relaxation time evaluation of knee cartilage: comparison of meniscus-intact and -injured knees after anterior cruciate ligament reconstruction

BACKGROUND

Associated meniscal injury is well recognized at anterior cruciate ligament (ACL) reconstruction, and it is a known risk factor for osteoarthritis.

PURPOSE

To evaluate and characterize the postoperative appearance of articular cartilage after different meniscal treatment in ACL-reconstructed knees using T2 relaxation time evaluation on MRI.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

A total of 62 consecutive patients who under ACL reconstruction were recruited in this study, including 23 patients undergoing partial meniscectomy (MS group), 21 patients undergoing meniscal repair (MR group), and 18 patients with intact menisci (MI group) at time of surgery. Clinical evaluation, including subjective functional scores and physical examination, was performed on the same day as the MRI examination and at follow-up times ranging from 2 to 4.2 years. The MRI multiecho sagittal images were segmented to determine the T2 relaxation time value of each meniscus and articular cartilage plate. Differences in each measurement were compared among groups.

RESULTS

No patient had joint-line tenderness or reported pain or clicking on McMurray test or instability. There were also no statistically significant differences in functional scores or medial or lateral meniscus T2 values among the 3 groups (P > .05 for both). There was a significantly higher articular cartilage T2 value in the medial femorotibial articular cartilage for the MS group (P < .01) and the MR group (P < .05) compared with that of the MI group, while there was no significant difference in articular cartilage T2 value between the MS and MR groups (P > .05) in each articular cartilage plate. The medial tibial articular cartilage T2 value had a significant positive correlation with medial meniscus T2 value (r = 0.287; P = .024) CONCLUSION: This study demonstrates that knees with meniscectomy or meniscal repair had articular cartilage degeneration at 2 to 4 years postoperatively, with higher articular cartilage T2 relaxation time values compared with the knees with an intact meniscus.

Comparison of femoral tunnel geometry, using in vivo 3-dimensional computed tomography, during transportal and outside-in single-bundle anterior cruciate ligament reconstruction techniques

PURPOSE

To compare the transportal (TP) and outside-in (OI) techniques regarding femoral tunnel position and geometry after anatomic single-bundle (SB) anterior cruciate ligament (ACL) reconstruction.

METHODS

This study included 51 patients who underwent anatomic SB ACL reconstruction with the TP (n = 21) or OI (n = 30) technique. All patients underwent 3-dimensional computed tomography 3 days after the operation. The femoral tunnel position (quadrant method), femoral graft bending angle, femoral tunnel length, and posterior wall breakage were assessed by immediate postoperative 3-dimensional computed tomography with OsiriX imaging software.

RESULTS

The OI technique had a shallower femoral tunnel position (arthroscopic position) than did the TP technique (P = .005). The mean femoral graft bending angle was significantly more acute with the OI technique (101.3° ± 8.2°) than with the TP technique (107.9° ± 10.0°) (P = .02). The mean femoral tunnel length was significantly greater with the OI technique (33.0 ± 3.5 mm) than with the TP technique (29.6 ± 3.9 mm) (P = .003). Posterior wall breakage occurred in 7 cases (33.3%) with the TP technique and 1 case (3.3%) with the OI technique (P = .02).

CONCLUSIONS

The mean femoral tunnel position was significantly shallower (arthroscopic position) with the OI technique than with the TP technique. The OI technique resulted in a more acute femoral graft bending angle, longer femoral tunnel length, and lower incidence of posterior wall breakage than did the TP technique. These results might be helpful for anatomic SB ACL reconstruction using TP and OI techniques.

LEVEL OF EVIDENCE

Level III, retrospective comparative study.

Long-term clinical and radiographic results after delayed anterior cruciate ligament reconstruction in adolescents

BACKGROUND

The risk of further intra-articular damage associated with nonoperative or delayed anterior cruciate ligament (ACL) reconstruction must be considered against the risk of growth disturbance with early reconstruction and transphyseal drilling. Long-term follow-ups after the surgical treatment of ACL injuries in adolescents are rare.

PURPOSE

To evaluate results 10 to 20 years after ACL reconstruction in terms of the radiographic presence of osteoarthritis, clinical assessments, and health-related quality of life in patients who were adolescents at the time of surgery.

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

Thirty-two adolescents (mean age, 15.2 years [range, 12-16 years]; 11 boys, 21 girls), with a symptomatic unilateral ACL rupture, underwent reconstruction using bone-patellar tendon-bone (n=10) or hamstring tendon (n=22) autografts at an almost skeletally mature age according to Tanner stage 4. Twenty-nine patients (91%) underwent clinical, radiographic, and health-related quality of life assessments after 10 to 20 years (mean, 175 months).

RESULTS

The mean time between the injury and index surgery was 11.6 months. The reconstructed knee had significantly more osteoarthritic changes compared with the noninvolved contralateral knee (P=.001). Preoperatively, the median Tegner activity level was 4 (range, 2-8), and the median Lysholm knee score was 75 (range, 50-90) points. At follow-up, the respective median values were 4 (range, 1-7) and 84 (range, 34-100) points (P=not significant [preoperatively vs follow-up]). The median finding for the single-legged hop test was 84% (range, 0%-105%) preoperatively and 93% (range, 53%-126%) at follow-up (P=.01). At follow-up, muscle strength measurements displayed more than 90% of the noninvolved leg in both extension and flexion. The manual Lachman test result was significantly improved at follow-up compared with preoperatively (P<.001). The 36-item Short Form Health Survey (SF-36) revealed scores comparable with those of healthy controls. The mean EuroQol (EQ-5D) score was 0.86±0.12. The Knee injury and Osteoarthritis Outcome Score (KOOS) values were lower in all dimensions compared with age-matched healthy controls.

CONCLUSION

In the long term, patients who were adolescents at the time of ACL reconstruction revealed significantly more radiographically visible osteoarthritic changes in their operated knee than in their noninvolved contralateral knee. Clinical outcomes and health-related quality of life are comparable with those of healthy controls.

Osteoarthritis prevalence following anterior cruciate ligament reconstruction: a systematic review and numbers-needed-to-treat analysis

OBJECTIVE

To determine the prophylactic capability of anterior cruciate ligament (ACL) reconstruction in decreasing the risk of knee osteoarthritis (OA) when compared with ACL-deficient patients, as well as the effect of a concomitant meniscectomy. We also sought to examine the influence of study design, publication date, and graft type as well as the magnitude of change in physical activity from preinjury Tegner scores in both cohorts.

DATA SOURCES

We searched Web of Science and PubMed databases from 1960 through 2012 with the search terms osteoarthritis, meniscectomy, anterior cruciate ligament, anterior cruciate ligament reconstruction, and anterior cruciate ligament deficient.

STUDY SELECTION

Articles that reported the prevalence of tibiofemoral or patellofemoral OA based on radiographic assessment were included. We calculated numbers needed to treat and relative risk reduction with associated 95% confidence intervals for 3 groups (1) patients with meniscal and ACL injury, (2) patients with isolated ACL injury, and (3) total patients (groups 1 and 2).

DATA EXTRACTION

A total of 38 studies met the criteria. Of these, 27 assessed the presence of tibiofemoral osteoarthritis in patients treated with anterior cruciate ligament reconstruction.

DATA SYNTHESIS

Overall, ACL reconstruction (ACL-R) yielded a numbers needed to treat to harm of 16 with a relative risk increase of 16%. Anterior cruciate ligament reconstruction along with meniscectomy yielded a numbers needed to treat to benefit of 15 and relative risk reduction of 11%. Isolated ACL-R showed a numbers needed to treat to harm of 8 and relative risk increase of 43%. Activity levels were decreased in both ACL-R (d = -0.90; 95% confidence interval = 0.77, 1.13) and ACL-deficient (d = -1.13; 95% confidence interval = 0.96, 1.29) patients after injury.

CONCLUSIONS

The current literature does not provide substantial evidence to suggest that ACL-R is an adequate intervention to prevent knee osteoarthritis. With regard to osteoarthritis prevalence, the only patients benefiting from ACL-R were those undergoing concomitant meniscectomy with reconstruction.

Lower risk of revision with patellar tendon autografts compared with hamstring autografts: a registry study based on 45,998 primary ACL reconstructions in Scandinavia

BACKGROUND

A number of studies have found comparable results after anterior cruciate ligament (ACL) reconstruction with patellar tendon autografts and hamstring autografts; however, few studies have been large enough to reveal differences in risk of revision with regard to clinical and demographic factors.

PURPOSE

To present the distribution of grafts for ACL reconstruction based on data in the Scandinavian ACL registries and to compare the risk of revision between patellar tendon autografts and hamstring autografts. Potential associations with other clinical and demographic factors were also explored.

STUDY DESIGN

Cohort study; Level of evidence, 2.

METHODS

A total of 45,998 primary ACL reconstructions, including 6736 patellar tendon autografts and 38,666 hamstring autografts, were identified in the Scandinavian ACL registries. The overall median follow-up time was 3 years (range, 0-8 years). To compare the risk of revision between groups of patients, univariate Kaplan-Meier analysis (with log-rank test) and the Cox proportional hazard regression model were applied. The hazard rate ratio with 95% CI was reported as a measure of effect.

RESULTS

Patellar tendon and hamstring autografts were used in 14.6% and 84.1% of the patients, respectively. The remaining patients received allografts, direct sutures, or other graft types (1.3%). The primary ACL injury occurred during soccer, team handball, or alpine activities in 67.5% of the patients in the patellar tendon group and 66.2% in the hamstring group. A total of 156 patients in the patellar tendon group and 1042 patients in the hamstring group underwent revision. The overall risk of revision was significantly lower in the patellar tendon group versus the hamstring group (hazard rate ratio = 0.63; 95% CI, 0.53-0.74), and it decreased with increasing age at surgery, although not strictly linearly. The lower risk of revision in the patellar tendon group was consistently observed across subgroups of patient sex, age, and concomitant cartilage injury (P > .05, test for interaction) but seemed to be slightly more pronounced for patients injured during certain pivoting activities (soccer, team handball, and alpine activities) compared with other activities (hazard rate ratio = 0.57 vs 0.81; P = .058, test for interaction).

CONCLUSION

The majority of primary ACL reconstructions in Scandinavia are performed with hamstring autografts. Results from the present large prospective study show that patients receiving patellar tendon autografts have a statistically significantly lower risk of revision compared with patients receiving hamstring autografts.

Arthroscopic BPTB graft reconstruction in ACL ruptures: 15-year results and survival

PURPOSE

The aim of this study is to investigate the 15-year results and survival of arthroscopic ACL reconstruction using the central-third patellar bone-tendon-bone (BPTB) autograft.

METHODS

ACL BPTB reconstruction was performed in 250 consecutive patients. Of these patients, 88% returned for a follow-up examination at 15 years after reconstruction. Therefore, 220 patients were studied. Mean time from injury to intervention was 3.4months (range 2 to 16). The parameters for assessment of results were subjective satisfaction, clinical examination (pivot-shift test, Lachman test with KT-1000), recovery of pre-injury activity level, and long-leg standing radiographs. We also evaluated the presence of meniscal and/or chondral injuries during the procedure. Failure rates were also evaluated. We defined a failure as severe instability not compatible with the activities of daily living (ADL) due to graft rupture.

RESULTS

8.2% of patients required a revision procedure because of graft rupture. In subjective terms, 98.1% of patients said that they were satisfied with the surgical outcomes after 15 years. Pivot shift test was normal in 93.5% at 15 years. Lachman test (KT-1000) was normal in 95.4% at 15 years. Fifteen years after surgery, 90% of patients recovered their pre-injury activity level. In 25.4% of patients symptomatic osteoarthritic changes in the knee were found at 15 years.

CONCLUSIONS

The survival prevalence of arthroscopic ACL reconstruction using the central-third patellar bone-tendon-bone (BPTB) autograft at 15 years was 94.8%. Fifteen years after surgery, 90% of patients recovered their pre-injury activity level. In 25.4% of patients symptomatic osteoarthritic changes in the knee were found at 15 years.

LEVEL OF EVIDENCE

Level IV.

Long-term results of a randomized study on anterior cruciate ligament reconstruction with or without a synthetic degradable augmentation device to support the autograft

PURPOSE

The aim was to compare the outcome of anterior cruciate ligament (ACL) reconstruction with bone-patellar tendon-bone (BPTB) autograft, with and without a poly(urethane urea) augmentation device.

METHODS

Patients were randomized to BPTB reconstruction with a synthetic degradable augmentation device (n = 96) or without augmentation (n = 105). Follow-ups were made during 4 years after surgical treatment with the KT1000 arthrometer for objective evaluation of sagittal stability. The Tegner scoring system for assessment of physical activity level and the Knee injury Osteoarthritis Outcome Score (KOOS) for assessment of knee-specific health were evaluated after 4 and 12 years.

RESULTS

KT1000 tests showed a significant decrease in mean manual maximum side-to-side difference after 4 years in both patients with and those without augmentation, without any statistical difference between the groups (n.s.). Pre-injury, 76 and 80% of the patients, respectively, reported Tegner level 7-10. Pre-surgery, the corresponding figures were 6 and 5%, and at 4 years, 33 and 30 %. Twelve years after ACL reconstruction, both groups had significantly higher KOOS scores in function in sports and recreational activities (p < 0.001) and knee-related quality of life (p < 0.001) compared to before surgical treatment. In 10 patients, the augmentation device was removed, in six of these because of insufficient screw fixation to femur and in four due to swelling/hydrops.

CONCLUSION

This study showed no significant difference in clinical outcome with use of an additional synthetic augmentation device in a single-bundle BPTB ACL reconstruction compared with non-augmentation, in short, intermediate, or long-term perspective.

LEVEL OF EVIDENCE

Therapeutic study, Level I.

Effects of various decellularization methods on histological and biomechanical properties of rabbit tendons

The aim of the present study was to investigate the effects of various decellularization methods on the histological and biomechanical properties of rabbit tendons. In total, six chemical reagents, including 1% t-octyl-phenoxypolyethoxyethanol (Triton-X 100), 0.5% sodium dodecyl sulfate (SDS), 1% tri-n-butyl phosphate (TnBP), 1% Triton-X 100 + 0.5% SDS, 1% TnBP + 0.5% SDS and 1% TnBP + 1% Triton-X 100, were used on rabbit semitendinosus muscles and flexor digitorum tendons for 24 h to remove cells. Hematoxylin and eosin staining was applied for histological observation, while tension testing was used for biomechanical studies. The effects of the various decellularization methods on the histological structure and biomechanical properties of rabbit tendons were evaluated. A group of fresh tendons treated with phosphate-buffered saline served as controls. The various decellularization methods resulted in different effects on the tendons. All the treatment groups exhibited a decrease in tendon biomechanical properties, but no statistically significant differences were observed among the experimental groups. The extensibility of the 1% TnBP-treated group was found to be greater than that of the other groups; however, the difference was not statistically significant. Histologically, the 1% TnBP + 0.5% SDS treatment was shown to have the least impact on the rabbit tendon structure, with good decellularization and no clear cellular remnants observed. The 1% Triton-X 100 + 0.5% SDS treatment had a pronounced effect on the tendon collagen structure and a number of collagen ruptures were observed. Overall, 1% TnBP + 0.5% SDS was found to be the most effective compared with the other treatments, as this treatment preserved the tendon collagen structure while completely removing the cells. Tendons treated with 1% TnBP + 0.5% SDS were histologically similar to normal tendon tissue and biomechanically similar to the tendons in the control group.

Increased risk of osteoarthritis after anterior cruciate ligament reconstruction: a 14-year follow-up study of a randomized controlled trial

BACKGROUND

The reported prevalence of radiological osteoarthritis (OA) after anterior cruciate ligament (ACL) reconstruction varies from 10% to 90%. Purpose/

HYPOTHESIS

To report the prevalence of OA after ACL reconstruction and to compare the OA prevalence between quadrupled semitendinosus tendon (ST) and bone-patellar tendon-bone (BPTB) grafts. The hypothesis was that there would be no difference in OA prevalence between the graft types. The secondary aim was to study whether patient characteristics and additional injuries were associated with long-term outcomes.

STUDY DESIGN

Randomized controlled trial; Level of evidence, 1.

METHODS

Radiological examination results, Tegner activity levels, and Knee injury and Osteoarthritis Outcome Score (KOOS) values were determined in 135 (82%) of 164 patients at a mean of 14 years after ACL reconstruction randomized to an ST or a BPTB graft. Osteoarthritis was defined according to a consensus by at least 2 of 3 radiologists of Kellgren-Lawrence grade ≥2. Using regression analysis, graft type, sex, age, overweight, time between injury and reconstruction, additional meniscus injury, and a number of other variables were assessed as risk factors for OA 14 years after ACL reconstruction.

RESULTS

Osteoarthritis of the medial compartment was most frequent, with 57% of OA cases in the ACL-reconstructed knee and 18% of OA cases in the contralateral knee (P < .001). There was no difference between the graft types: 49% of OA of the medial compartment for BPTB grafts and 65% for ST grafts (P = .073). The KOOS results were lower for patients with OA in all subscales, indicating that OA was symptomatic. No difference in the KOOS between the graft types was found. Meniscus resection was a strong risk factor for OA of the medial compartment (odds ratio, 3.6; 95% CI, 1.4-9.3) in the multivariable logistic regression analysis.

CONCLUSION

A 3-fold increased prevalence of OA was found after an ACL injury treated with reconstruction compared with the contralateral healthy knee. No differences in the prevalence of OA between the BPTB and quadrupled ST reconstructions were found. An initial meniscus resection was a strong risk factor for OA; the time between injury and reconstruction was not.