Arthroscopic anterior cruciate ligament reconstruction using fresh-frozen bone plug-free allogeneic tendons: 10-year follow-up

Influence of a Concomitant Medial Meniscus Injury on Knee Joint Function and Osteoarthritis Presence after Anterior Cruciate Ligament Reconstruction

(1) Background: The aim of this study was to investigate how a medial meniscus injury accompanying an anterior cruciate ligament rupture affects the clinical outcome 10 years after ACL reconstruction. (2) Methods: A total of 37 patients who received anterior cruciate ligament reconstruction (ACLR) were included in this retrospective study. Two groups were analyzed at a single follow-up of 10 years: (i) "isolated (ACLR)" (n = 20) and (ii) "ACLR with medial meniscal injury" (n = 17). The following clinical scores were recorded: International Knee Documentation Committee (IKDC), the Knee Injury and Osteoarthritis Outcome Score (KOOS), Lysholm Score and Tegner Activity Score. To determine the degree of osteoarthritis the Kellgren-Lawrence score was used. (3) Results: The "isolated ACLR" study group scored significantly higher (p < 0.05) on the IKDC subjective questionnaire (mean: 88.4) than the "ACLR with medial meniscus injury" group (mean: 81). The KOOS category "activities of daily living" showed significantly better results in the isolated ACLR group (p < 0.05). The "ACLR with medial meniscus injury" group had significantly higher degree of osteoarthritis (p < 0.05). No significant differences were found in all the other clinical scores. (4) Conclusions: The results of this study further indicate that patients with a concomitant medial meniscus injury have slightly more discomfort in everyday life and increased risk of developing osteoarthritis 10 years after surgery.

Prevalence of post-traumatic osteoarthritis after anterior cruciate ligament injury remains high despite advances in surgical techniques

Aims

The aim of this study was to report the pooled prevalence of post-traumatic osteoarthritis (PTOA) and examine whether the risk of developing PTOA after anterior cruciate ligament (ACL) injury has decreased in recent decades.

Methods

The PubMed and Web of Science databases were searched from 1 January 1980 to 11 May 2022. Patient series, observational studies, and clinical trials having reported the prevalence of radiologically confirmed PTOA after ACL injury, with at least a ten-year follow-up, were included. All studies were analyzed simultaneously, and separate analyses of the operative and nonoperative knees were performed. The prevalence of PTOA was calculated separately for each study, and pooled prevalence was reported with 95% confidence intervals (CIs) using either a fixed or random effects model. To examine the effect of the year of injury on the prevalence, a logit transformed meta-regression analysis was used with a maximum-likelihood estimator. Results from meta-regression analyses were reported with the unstandardized coefficient (β).

Results

The pooled prevalence of PTOA was 37.9% (95% CI 32.1 to 44) for operatively treated ACL injuries with a median follow-up of 14.6 years (interquartile range (IQR) 10.6 to 16.7). For nonoperatively treated ACL injuries, the prevalence was 40.5% (95% CI 28.9 to 53.3), with a median of follow-up of 15 years (IQR 11.7 to 20.0). The association between the year of operation and the prevalence of PTOA was weak and imprecise and not related to the choice of treatment (operative β -0.038 (95% CI -0.076 to 0.000) and nonoperative β -0.011 (95% CI -0.101 to 0.079)).

Conclusion

The initial injury, irrespective of management, has, by the balance of probability, resulted in PTOA within 20 years. In addition, the prevalence of PTOA has only slightly decreased during past decades. Therefore, further research is warranted to develop strategies to prevent the development of PTOA after ACL injuries.

Weight Is a Predictor of Delayed Operation Time in Primary Isolated Anterior Cruciate Ligament Reconstruction

BACKGROUND

Few studies have evaluated the impact of obesity on operation time in patients with ACL reconstruction. The purpose of this study was to understand the effect of obesity on operation time in patients with arthroscopic anterior cruciate ligament (ACL) reconstruction.

METHODS

A total of 103 patients were included. The mean pure operation time was 45.9 ± 13.4 min. Considering that 15 min incremental increases in operation time are an independent risk factor for complications, all patients were classified into two groups according to operation time: more or less than 61 min. Demographic data were compared between both groups. Pure operation time was defined as operative time without suture time (pure operation time = suture start time - operation start time). Correlation analysis between demographic data and pure operation time was performed, and multiple linear regression analysis was used to identify the predictors of pure operation time.

RESULTS

The pure operation time ≥61 min group (n = 34) had a 14.7 kg higher weight and 4.5 kg/m2 higher body mass index (BMI) than those with pure operation time < 61 min (n = 69). Weight (r = 0.635, p < 0.001) and BMI (r = 0.584, p < 0.001) were positively correlated with operation time. Multiple linear regression analysis showed that weight (β = 0.635, p < 0.001) was the only predictor of operation time. A weight of 74.25 kg was a cut-off value for a pure operation time of >61 min.

CONCLUSIONS

The weight and BMI of the group with pure operation time of ≥61 min were 14.7 kg and 4.5 kg/m2 higher, respectively. The weight of patients with ACL tears was a factor affecting delay in the operation time. Patients weighing over 74.25 kg were more likely to delay ACL reconstruction.

Potential causal role of synovial complement system activation in the development of post-traumatic osteoarthritis after anterior cruciate ligament injury or meniscus tear

Anterior cruciate ligament (ACL) injury and meniscal tear (MT) are major causal factors for developing post-traumatic osteoarthritis (PTOA), but the biological mechanism(s) are uncertain. After these structural damages, the synovium could be affected by complement activation that normally occurs in response to tissue injury. We explored the presence of complement proteins, activation products, and immune cells, in discarded surgical synovial tissue (DSST) collected during arthroscopic ACL reconstructive surgery, MT-related meniscectomy and from patients with OA. Multiplexed immunohistochemistry (MIHC) was used to determine the presence of complement proteins, receptors and immune cells from ACL, MT, OA synovial tissue vs. uninjured controls. Examination of synovium from uninjured control tissues did not reveal the presence of complement or immune cells. However, DSST from patients undergoing ACL and MT repair demonstrated increases in both features. In ACL DSST, a significantly higher percentage of C4d+, CFH+, CFHR4+ and C5b-9+ synovial cells were present compared with MT DSST, but no major differences were seen between ACL and OA DSST. Increased cells expressing C3aR1 and C5aR1, and a significant increase in mast cells and macrophages, were found in ACL as compared to MT synovium. Conversely, the percentage of monocytes was increased in the MT synovium. Our data demonstrate that complement is activated in the synovium and is associated with immune cell infiltration, with a more pronounced effect following ACL as compared to MT injury. Complement activation, associated with an increase in mast cells and macrophages after ACL injury and/or MT, may contribute to the development of PTOA.

Metabolomic Phenotypes Reflect Patient Sex and Injury Status: A Cross-Sectional Analysis of Human Synovial Fluid

Background

Post-traumatic osteoarthritis (PTOA) is caused by knee injuries like anterior cruciate ligament (ACL) injuries. Often, ACL injuries are accompanied by damage to other tissues and structures within the knee including the meniscus. Both are known to cause PTOA but underlying cellular mechanisms driving disease remain unknown. Aside from injury, patient sex is a prevalent risk factor associated with PTOA.

Hypothesis

Metabolic phenotypes of synovial fluid that differ by knee injury pathology and participant sex will be distinct from each other.

Study Design

A cross-sectional study.

Methods

Synovial fluid from n=33 knee arthroscopy patients between 18 and 70 years with no prior knee injuries was obtained pre-procedure and injury pathology assigned post-procedure. Synovial fluid was extracted and analyzed via liquid chromatography mass spectrometry metabolomic profiling to examine differences in metabolism between injury pathologies and participant sex. Additionally, samples were pooled and underwent fragmentation to identify metabolites.

Results

Metabolite profiles revealed that injury pathology phenotypes were distinct from each other where differences in endogenous repair pathways that are triggered post-injury were detected. Specifically, acute differences in metabolism mapped to amino acid metabolism, lipid-related oxidative metabolism, and inflammatory-associated pathways. Lastly, sexual dimorphic metabolic phenotypes were examined between male and female participants, and within injury pathology. Specifically, Cervonyl Carnitine and other identified metabolites differed in concentration between sexes.

Conclusions

The results of this study suggest that different injuries (e.g., ligament vs. meniscus), as well as sex are associated with distinct metabolic phenotypes. Considering these phenotypic associations, a greater understanding of metabolic mechanisms associated with specific injuries and PTOA development may yield data regarding how endogenous repair pathways differ between injury types. Furthermore, ongoing metabolomic analysis of synovial fluid in injured male and female patients can be performed to monitor PTOA development and progression.

Clinical Relevance

Extension of this work may potentially lead to the identification of biomarkers as well as drug targets that slow, stop, or reverse PTOA progression based on injury type and patient sex.

Early zoledronate treatment inhibits subchondral bone microstructural changes in skeletally-mature, ACL-transected canine knees

Anterior cruciate ligament (ACL) tear leads to post-traumatic osteoarthritis (PTOA), a significant clinical burden worldwide that currently has no cure. Recent studies suggest a role of subchondral bone adaptations in the development of PTOA. Particularly, microstructural changes in the rod-and-plate microstructure of subchondral bone may precede and contribute to OA progression. In this study, we quantified microstructural changes in subchondral trabecular rods and plates after ACL-transection for the first time in the well-established preclinical canine model of PTOA and investigated the therapeutic potentials of a bisphosphonate (zoledronate) and NSAID treatment (meloxicam). Unilateral hindlimb ACL transection was performed on skeletally-mature (2-year-old, N = 20) and juvenile (10-month-old, N = 20) male beagles. Animals were assigned to 4 groups (N = 5): ACLT, un-operated control, ACLT with zoledronate, and ACLT with meloxicam treatment. Subchondral bone microstructure was evaluated by micro-computed tomography and cartilage integrity was evaluated histologically. We found that ACL-induced subchondral bone changes depended on skeletal maturity of animals. In mature animals, significant loss of trabecular plates that resulted in reduced PR ratio occurred at Month 1 and persisted until Month 8. Zoledronate treatment prevented trabecular plate loss while meloxicam treatment did not. Whether cartilage degeneration is also attenuated warrants further investigation. In juvenile animals that have not reached skeletal maturity, transient changes in trabecular plate and rod microstructure occurred at Month 3 but not Month 9. Neither zoledronate nor meloxicam treatment attenuated bone microstructural changes or cartilage damages. Findings from this study suggest that early inhibition of bone resorption by bisphosphonate after injury may be a promising therapeutic approach to prevent alterations in subchondral bone microstructure associated with PTOA. Our results further demonstrate that pathogenesis of PTOA may differ between adolescent and adult patients and therefore require distinct management strategies.

A review of Risk Factors for Post-traumatic hip and knee osteoarthritis following musculoskeletal injuries other than anterior cruciate ligament rupture

Post-traumatic osteoarthritis (PTOA) is a common form of osteoarthritis that might occur after any joint trauma. Most PTOA publications mainly focus on anterior cruciate ligament (ACL) injuries. However, many other traumatic injuries are associated with PTOA, not only for the knee but also for the hip joint. We aim to identify and summarize the existing literature on the musculoskeletal injuries associated with knee and hip PTOA and their risk factors in determining those with a worse prognosis, excluding ACL injuries. Despite the narrative nature of this review, a systematic search for published studies in the last twenty years regarding the most relevant injuries associated with a higher risk of PTOA and associated risk factors for OA was conducted. This review identified the six more relevant injuries associated with knee or hip PTOA. We describe the incidence, risk factors for the injury and risk factors for PTOA of each. Meniscal injury, proximal tibial fracture, patellar dislocation, acetabular, femoral fractures and hip dislocations are all discussed in this review.

Aseptically Processed Allograft Implantation: A Safe Strategy for Knee Ligament Reconstructions

Postoperative infections after allograft implantation is a major concern in knee ligament reconstructions considering the theoretical risk of disease transmission and its potential severity. Here, we aimed to evaluate the postoperative infection rate after knee ligament reconstructions using aseptically processed allografts, and provide an overview of the allografts use in an academic tertiary hospital. A retrospective study was performed evaluating patients who underwent knee ligament reconstructions using aseptically processed allografts, including primary and revision surgeries, from 2005 to 2018. Demographic data, including the type of knee injury and trauma energy, and postoperative data were collected focusing on postoperative infections. Regarding these infected cases, further analyses were performed considering the presenting signs and symptoms, the isolated microorganism identified in culture, the time between graft implantation and diagnosis of infection (defined as acute, subacute, and late), and the need for graft removal. A total of 180 cases of ligament reconstructions were included. The mean follow-up was 8.2 (range: 2.1-15.6) years and the mean age at surgery was 34.1 (± 11.1) years. A total of 262 allografts were implanted in those 180 cases, 93 (35.5%) as bone plug allografts and 169 (64.5%) as soft tissue allografts. Common surgical indications included multiligament reconstruction (57.2%) and primary anterior cruciate ligament (ACL) reconstruction (15%). Seven cases (3.9%) presented postoperative infections. Knee pain (100%) and swelling (100%) were the most prevalent symptoms. Two cases (28.6%) presented sinus tract. Allografts were removed in two cases, the same cases that presented draining sinus (p = 0.04). High-energy trauma was the only statistically associated factor for infection (p = 0.04). No significant association between infection and the type of allograft (p > 0.99) or sex (p = 0.35) were observed. Four cases (57.1%) had monomicrobial staphylococcal infections. Based on that, the allograft-related infection rate was 1.7% (the remaining three infected cases). Nonirradiated, aseptically processed allografts have a low postoperative infection rate in knee ligament reconstructions, being a safe alternative for surgeries that require additional source, increased variety, and quantity of grafts.

Knee Surgery Is Associated With Greater Odds of Knee Osteoarthritis Diagnosis

CONTEXT

Knee osteoarthritis (OA) frequently develops following knee injury/surgery. It is accepted that knee injury/surgery precipitates OA with previous studies examining this link in terms of years after injury/surgery. However, postinjury OA prevalence has not been examined by decade of life; thereby, limiting our understanding of the age at which patients are diagnosed with posttraumatic knee OA.

OBJECTIVE

Evaluate the association between the knee injury and/or surgical history, present age, and history of receiving a diagnosis of knee OA.

DESIGN

Cross-sectional survey.

SETTING

Online survey.

PARTICIPANTS

A total of 3660 adults were recruited through ResearchMatch©. Of these, 1723 (47.1%) were included for analysis due to history of (1) knee surgery (SURG: n = 276; age = 53.8 [15.3] y; and body mass index [BMI] = 29.9 [8.0] kg/m2), (2) nonsurgical knee injury (INJ: n = 449; age = 46.0 [15.6] y; and BMI = 27.5 [6.9] kg/m2), or (3) no knee injury (CTRL: n = 998; age = 44.0 [25.2] y; and BMI = 26.9 [6.6] kg/m2). Respondents were subdivided by decade of life (20-29 through 70+).

INTERVENTION

An electronic survey regarding knee injury history, treatment, and diagnosis of knee OA.

MAIN OUTCOME MEASURES

Binary logistic regression determined the association between knee surgical status and OA by decade of life. Participants with no histories of OA or lower-extremity injury were the referent categories. BMI was a covariate in all analyses.

RESULTS

SURG respondents were more likely to report having knee OA than CTRL for all age groups (odds ratios: 11.43-53.03; P < .001). INJ respondents aged 30 years and older were more likely to have OA than CTRL (odds ratios: 2.99-14.22; P < .04). BMI influenced associations for respondents in their 50s (P = .001) and 60s (P < .001) only.

CONCLUSIONS

INJ increased the odds of reporting a physician diagnosis of knee OA in adults as young as 30 to 39 years. Importantly, SURG yielded 3 to 4 times greater odds of being diagnosed with knee OA compared with INJ in adults as young as 20 to 29 years. Delaying disease onset in these young adults is imperative to optimize the quality of life long term after surgery.

The use of allograft tendons in primary ACL reconstruction

PURPOSE

Graft choice in primary anterior cruciate ligament (ACL) reconstruction remains controversial. The use of allograft has risen exponentially in recent years with the attraction of absent donor site morbidity, reduced surgical time and reliable graft size. However, the published evidence examining their clinical effectiveness over autograft tendons has been unclear. The aim of this paper is to provide a current review of the clinical evidence available to help guide surgeons through the decision-making process for the use of allografts in primary ACL reconstruction.

METHODS

The literature in relation to allograft healing, storage, sterilisation, differences in surgical technique and rehabilitation have been reviewed in addition to recent comparative studies and all clinical systematic reviews and meta-analyses.

RESULTS

Early reviews have indicated a higher risk of failure with allografts due to association with irradiation for sterilisation and where rehabilitation programs and post-operative loading may ignore the slower incorporation of allografts. More recent analysis indicates a similar low failure rate for allograft and autograft methods of reconstruction when using non-irradiated allografts that have not undergone chemically processing and where rehabilitation has been slower. However, inferior outcomes with allografts have been reported in young (< 25 years) highly active patients, and also when irradiated or chemically processed grafts are used.

CONCLUSION

When considering use of allografts in primary ACL reconstruction, use of irradiation, chemical processing and rehabilitation programs suited to autograft are important negative factors. Allografts, when used for primary ACL reconstruction, should be fresh frozen and non-irradiated. Quantification of the risk of use of allograft in the young requires further evaluation.

LEVELS OF EVIDENCE

III.

Meniscal repair concurrent with anterior cruciate ligament reconstruction restores posterior shift of the medial meniscus in the knee-flexed position

PURPOSE

The purpose of this study was to evaluate the shape and shift of the medial meniscus before and after meniscal repair concurrent with anterior cruciate ligament (ACL) reconstruction using magnetic resonance imaging (MRI) at 90° of knee flexion.

METHODS

This study included 18 patients with ACL-deficient knees without meniscus tears (group A), 11 patients with medial meniscus tears alone (group M), and 15 patients with ACL-deficient knees complicated with medial meniscus tears (group AM). The posterior segment shape was evaluated using open MRI at 90° of knee flexion preoperatively and at 3 months postoperatively. The length, height, width, and posterior extrusion of the medial meniscus and posterior tibiofemoral distance were measured. These measurements were compared between the three groups.

RESULTS

On preoperative MRI, a significant difference was observed in the posterior extrusion of the medial meniscus (group A, 1.2 ± 0.5 mm; group M, 1.7 ± 0.3 mm; group AM, 4.1 ± 1.5 mm, p < 0.001). All parameters did not differ between the three groups on postoperative MRI. In addition, the posterior width and extrusion of the medial meniscus were decreased significantly after meniscal repair concurrent with ACL reconstruction.

CONCLUSIONS

This study demonstrated that the medial meniscus shifted posteriorly at 90° of knee flexion in ACL-deficient knees complicated with medial meniscus tears. Medial meniscal repair concurrent with ACL reconstruction improved the deformed morphology and posterior extrusion. MRI measurements of the posterior extrusion at the knee-flexed position may be clinically useful to assess the functional improvement of the medial meniscus following meniscal repair combined with ACL reconstruction.

LEVEL OF EVIDENCE

III.

A study of the relationship between meniscal injury and bone microarchitecture in ACL reconstructed knees

BACKGROUND

Anterior cruciate ligament (ACL) tears increase the risk of developing knee osteoarthritis. This risk increases further with concurrent meniscus injury. The role of bone changes during knee osteoarthritis development are not well-understood, but may be important to its etiology.

PURPOSE

To explore the effects of ACL tears on bone mineral density (BMD) and bone microarchitecture at five years post-op and their relationship to meniscal pathology, using high-resolution peripheral quantitative computed tomography (HR-pQCT).

METHODS

Twenty-eight participants with unilateral ACL reconstructions five years prior and no evidence of clinical or radiographic osteoarthritis were recruited. All participants represented one of three meniscus statuses: meniscus intact, meniscus repair, or meniscectomy. BMD and bone microarchitecture of the subchondral bone plate and adjacent trabecular bone were assessed using HR-pQCT, and percent-differences between the injured and contralateral knee were determined.

RESULTS

Subchondral bone plate thickness in the lateral femoral condyle was higher in the reconstructed knee (9.0%, p = 0.002), driven by the meniscus repair and meniscectomy groups (15.2% to 15.4%, p < 0.05). Trabecular BMD was lower in the reconstructed knee in the medial femoral condyle (-4.8% to -7.6%, p < 0.05), driven by all meniscus statuses. In the lateral compartments, few differences in trabecular bone were found. However, accounting for meniscus status, the meniscus intact group had lower trabecular BMD throughout both femur and tibia.

CONCLUSIONS

Five years post-op, reconstructed knees demonstrated detectable differences in BMD and bone microarchitecture, despite having normal radiographs. Meniscus damage affected primarily the lateral compartment, warranting further investigation to determine if these changes relate to osteoarthritis development.

The Cost-Effectiveness of Meniscal Repair Versus Partial Meniscectomy in the Setting of Anterior Cruciate Ligament Reconstruction

PURPOSE

To compare the cost-effectiveness of anterior cruciate ligament (ACL) reconstruction with meniscal repair to ACL reconstruction with partial meniscectomy.

METHODS

A decision-analytic Markov disease progression model with a 40-year horizon was created simulating outcomes after both meniscal repair and partial meniscectomy at the time of ACL reconstruction. Event probabilities, costs, and utilities were used for the index procedures. The development of osteoarthritis and subsequent knee replacement were either calculated or selected from published literature. Difference in cost, difference in quality-adjusted life-years (QALYs), and incremental cost-effective ratio were calculated to determine which index procedure is most cost-effective.

RESULTS

There is total direct cost from ACL reconstruction with meniscus repair of $17,898 compared with that with partial meniscectomy of $24,768 (cost savings of $6,870). There was an estimated gain of 18.00 QALYs after ACL reconstruction with meniscus repair compared with 17.16 QALYs with partial meniscectomy (increase of 0.84 QALYs). In this scenario, meniscus repair is the dominant index procedure at the time of ACL reconstruction.

CONCLUSIONS

Meniscal repair at the time of ACL reconstruction is more cost-effective than partial meniscectomy.

LEVEL OF EVIDENCE

Level IV, economic and decision analysis.

Variance in Anterior Cruciate Ligament Reconstruction Graft Selection based on Patient Demographics and Location within the Multicenter Orthopaedic Outcomes Network Cohort

The purpose of this study is to determine whether any regional or age-related patterns exist in graft choice for patients undergoing primary anterior cruciate ligament reconstruction (ACLR) within a large multicenter consortium. A retrospective cohort study was performed using data collected from the Multicenter Orthopaedic Outcomes Network (MOON) on patients having undergone primary ACLR. Patients were stratified by age group (younger than 20, 20-29, 30-39, 40-49, and 50+ years) and four demographic regions (Midwest, Southeast, Northeast, and West). A total of 2,149 patients (1,288 males, 861 females) were included. At least 70% of the patients were treated by a single surgeon in three of the four demographic regions. There were no clinically significant differences in body mass index (BMI), and no statistically significant differences in Marx activity rating scale (p > 0.05) between regions within any particular age group. There were significant differences in the proportion of autografts versus allografts used for primary ACLR between regions in every age group (p < 0.01). There were also significant differences in autograft (p < 0.001) and allograft (p < 0.001) harvest location based on demographic region. The Southeast and Northeast were more likely to use bone-patellar-tendon-bone autograft while the West and Midwest were likely to use hamstring autograft. Within our consortium, regional patterns exist both in autograft versus allograft use in patients undergoing primary ACLR, as well as harvest location of autografts and allografts. Given the similarities in average patient BMI and activity level between regions, as well as the single surgeon influence in three of the four regions, the regional patterns in graft use are likely due to surgeon preference.

Complications following harvesting of patellar tendon or hamstring tendon grafts for anterior cruciate ligament reconstruction: Systematic review of literature

Anterior cruciate ligament (ACL) reconstruction can be performed with an autograft, which is most often harvested from the patient's hamstring tendon (HT) or patellar tendon (PT). However, autograft harvesting leads to morbidity that is by no means insignificant. A systematic review of literature was performed to define the incidence of complications related to graft harvesting and the methods to prevent these complications. In March 2017, a systemic review of literature was performed using the keywords"harvesting", "harvest", "morbidity", "complication", "cruciate ligament". No time limit was applied. The studies had to be written in French or English with their abstract available online. This initial search based on the title and abstract identified 133 articles. Two independent observers analyzed each article entirely, including the references. In all, 36 articles were retained. The main complication of HT harvesting was sensory deficit because of damage to the infrapatellar branches of the saphenous nerve. This complication occurred in 39.7% to 88% of patients. This risk can be reduced by using a horizontal or oblique incision. The main complication following PT harvesting is anterior knee pain, reported in up to 46% of patients. There are substantial numbers of short-, medium- and long-term complications related to the harvesting of the two main ACL autografts. Effective means of prevention exist to reduce the risk of these complications.

LEVEL OF EVIDENCE

II Systematic review of literature.

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.

Epidemiology of Posttraumatic Osteoarthritis

Osteoarthritis is a leading cause of disability whose prevalence and incidence continue to increase. History of joint injury represents an important risk factor for posttraumatic osteoarthritis and is a significant contributor to the rapidly growing percentage of the population with osteoarthritis. This review will present the epidemiology associated with posttraumatic osteoarthritis, with particular emphasis on the knee and ankle joints. It is important to understand the effect of posttraumatic osteoarthritis on the population so that sufficient resources can be devoted to countering the disease and promoting optimal long-term health for patients after joint injury.

Hamstring tendon autograft versus fresh-frozen tibialis posterior allograft in primary arthroscopic anterior cruciate ligament reconstruction: a retrospective cohort study with three to six years follow-up

INTRODUCTION

Selection of various grafts for anterior cruciate ligament (ACL) reconstructions have been employed in order to improve on stability and function of the knee. This study aimed to compare stability and function of the knee after ACL arthroscopic reconstruction by single-loop tibialis posterior (TP) allograft and four-strand hamstring tendon (HT) autograft.

MATERIALS AND METHODS

The retrospective cohort study included 104 patients in the TP group matched with 118 patients in the HT group in terms of demographic characteristics, associated meniscus injury, subjective and objective knee characteristics. All patients were followed up for at least three years with regards to mentioned criteria and time of return to former activities.

RESULTS

The mean (range) age of TP (88 males and 16 females) and HT (99 males and 19 females) groups was 34.4 (19-48) and 36.9 (20-51) years, respectively. Median (range) follow-up durations were 55 (37-71) and 56 (36-72) months, respectively. No significant differences were observed post-operatively, regarding subjective and objective evaluations. Additionally, time duration for return to former activity was similar in both groups. Post-operative paresthesia and numbness of medial aspect of the calf were observed for two months in eight patients of the HT group which persisted to the final visit in one case. No similar symptom was seen in the TP group.

CONCLUSION

In arthroscopic ACL reconstruction, fresh frozen doubled TP allograft compared to HT autograft was equally effective in restoring function and stability of knee, permitting return to former activities.

LEVEL OF EVIDENCE

Retrospective comparative, Level III.

Anterior Cruciate Ligament Reconstruction: A 2015 global perspective of the Magellan Society

Background/objective

The Magellan Society is composed of > 150 high-volume fellowship-trained sports surgeons from four continents. These surgeons represent their regional sports organisations in travelling fellowships and are considered to be opinion leaders in their respective organisations. Prior to the 2014 Magellan Meeting in Arima, Japan, a survey was conducted to understand how Magellan members perform anterior cruciate ligament (ACL) reconstruction. This study aims to better understand how ACL reconstruction is performed by sports surgeons worldwide and to determine differences in surgical practice.

Methods

A survey was conducted prior to the Magellan Meeting in Arima, Japan. Information on ACL graft of choice for primary surgery and revision surgery, preferred surgical techniques, and femoral and tibial graft fixation methods was collected. The incidence of meniscal tears and the management of injuries in ACL surgery were also studied. The results of the survey are discussed in this article.

Results

A response rate of 51% (72 member respondents) was achieved for this survey. Hamstring autograft (58%) was the graft of choice for primary ACL reconstruction. The next most common autograft used was bone patella tendon bone autograft (28%). Allograft was the graft of choice in only 4% of respondents. The region of origin of surgeons and the age of surgeons were factors in the ACL graft of choice. Seventy-five percent of surgeons practised single-bundle ACL reconstructions only, 22% performed both single-bundle and double-bundle ACL reconstructions, and 3% performed double-bundle ACL reconstructions exclusively. Sixty-two percent of the respondents drilled femoral tunnels using the anteromedial portal technique. Meniscus repairs were performed in 25% of ACL reconstructions, on average.

Conclusion

Based on the survey, hamstring transportal anatomic single-bundle ACL reconstruction with meniscus preservation is the preferred ACL reconstruction technique of high-volume fellowship-trained sports surgeons.

Analysis of irradiation on the clinical effectiveness of allogenic tissue when used for primary anterior cruciate ligament reconstruction

BACKGROUND

It is unclear whether the use of low-dose irradiation or other tissue-processing methods, such as preservation by fresh-frozen (FF), freeze-drying (FD), or cryopreservation (CP) methods, affects the clinical outcomes of primary anterior cruciate ligament reconstruction (ACLR) using allograft.

HYPOTHESIS

Low-dose gamma irradiation (<2.5 Mrad) and method of allograft preservation do not affect subjective and objective clinical outcomes after primary ACLR in studies reviewed between November 2010 and September 2012.

STUDY DESIGN

Systematic review; Level of evidence, 3.

METHODS

A computerized search of multiple electronic databases was conducted from November 2010 to September 2012 for prospective and retrospective studies involving primary allograft ACLR. Inclusion criteria were English-language publications with a minimum average of 2 years' follow-up. Studies were excluded if they involved revision surgery, open surgery, multiple ligament procedures, autograft, xenograft, meniscal allograft, skeletally immature patients, or grafts treated with ethylene oxide, Tutoplast, or irradiation>2.5 Mrad or if the tissue-processing methods were not specified. Clinical outcomes were evaluated using the Lysholm score, Tegner score, International Knee Documentation Committee (IKDC) score, KT-1000/2000 arthrometer score, Lachman test, and pivot-shift test, as well as by assessing complications related to graft rupture, revision surgery, and infections.

RESULTS

A total of 21 publications met the criteria, involving a total of 1453 patients, with 415 irradiated and 1038 nonirradiated allografts. Mean follow-up was 49.8 months (range, 12-170 months). Mean age of the patients was 32.2 years. Knees with nonirradiated allografts had higher mean Lysholm scores (89.8 vs 84.4; P<.05), and a higher proportion of <5-mm difference on KT-1000/2000 arthrometer (0.97 vs 0.84; P<.0001), grade 0 and 1 pivot-shift (0.99 vs 0.94; P<.0001), and grade 0 and 1 Lachman (0.94 vs 0.89; P<.01) than those with irradiated grafts. Knees with irradiated allografts had a higher proportion of grade A and B IKDC outcomes (0.91 vs 0.86; P<.05) and revision surgery (0.0250 vs 0.0022; P<.001) compared with those with nonirradiated allografts. The lack of data for FD and CP allografts meant no statistical analysis could be made comparing FF versus FD versus CP allografts. The effect of irradiation was similar within FF allografts. The effect of graft type and surgical technique could not be determined because of insufficient data.

CONCLUSION

These results suggest that primary ACLRs using nonirradiated allografts may provide superior clinical outcomes than those using low-dose (<2.5 Mrad) irradiated grafts.

Incidence and trends of anterior cruciate ligament reconstruction in the United States

BACKGROUND

Anterior cruciate ligament (ACL) injury is among the most commonly studied injuries in orthopaedics. The previously reported incidence of ACL injury in the United States has varied considerably and is often based on expert opinion or single insurance databases.

PURPOSE

To determine the incidence of ACL reconstruction (ACLR) in the United States; to identify changes in this incidence between 1994 and 2006; to identify changes in the demographics of ACLR over the same time period with respect to location (inpatient vs outpatient), sex, and age; and to determine the most frequent concomitant procedures performed at the time of ACLR.

STUDY DESIGN

Descriptive epidemiological study.

METHODS

International Classification of Diseases, 9th Revision (ICD-9) codes 844.2 and 717.83 were used to search the National Hospital Discharge Survey (NHDS) and the National Survey of Ambulatory Surgery (NSAS) for the diagnosis of ACL tear, and the procedure code 81.45 was used to search for ACLR. The incidence of ACLR in 1994 and 2006 was determined by use of US Census Data, and the results were then stratified based on patient age, sex, facility, concomitant diagnoses, and concomitant procedures.

RESULTS

The incidence of ACLR in the United States rose from 86,687 (95% CI, 51,844-121,530; 32.9 per 100,000 person-years) in 1994 to 129,836 (95% CI, 94,993-164,679; 43.5 per 100,000 person-years) in 2006 (P = .015). The number of ACLRs increased in patients younger than 20 years and those who were 40 years or older over this 12-year period. The incidence of ACLR in females significantly increased from 10.36 to 18.06 per 100,000 person-years between 1994 and 2006 (P = .0003), while that in males rose at a slower rate, with an incidence of 22.58 per 100,000 person-years in 1994 and 25.42 per 100,000 person-years in 2006. In 2006, 95% of ACLRs were performed in an outpatient setting, while in 1994 only 43% of ACLRs were performed in an outpatient setting. The most common concomitant procedures were partial meniscectomy and chondroplasty.

CONCLUSION

The incidence of ACLR increased between 1994 and 2006, particularly in females as well as those younger than 20 years and those 40 years or older. Research efforts as well as cost-saving measures may be best served by targeting prevention and outcomes measures in these groups. Surgeons should be aware that concomitant injury is common.

Imaging following acute knee trauma

Joint injury has been recognized as a potent risk factor for the onset of osteoarthritis. The vast majority of studies using imaging technology for longitudinal assessment of patients following joint injury have focused on the injured knee joint, specifically in patients with anterior cruciate ligament injury and meniscus tears where a high risk for rapid onset of post-traumatic osteoarthritis is well known. Although there are many imaging modalities under constant development, magnetic resonance (MR) imaging is the most important instrument for longitudinal monitoring after joint injury. MR imaging is sensitive for detecting early cartilage degeneration and can evaluate other joint structures including the menisci, bone marrow, tendons, and ligaments which can be sources of pain following acute injury. In this review, focusing on imaging following acute knee trauma, several studies were identified with promising short-term results of osseous and soft tissue changes after joint injury. However, studies connecting these promising short-term results to the development of osteoarthritis were limited which is likely due to the long follow-up periods needed to document the radiographic and clinical onset of the disease. Thus, it is recommended that additional high quality longitudinal studies with extended follow-up periods be performed to further investigate the long-term consequences of the early osseous and soft tissue changes identified on MR imaging after acute knee trauma.

Anterior cruciate ligament injury and radiologic progression of knee osteoarthritis: a systematic review and meta-analysis

BACKGROUND

Knee osteoarthritis after anterior cruciate ligament (ACL) injury has previously been reported. However, there has been no meta-analysis reporting the development and progression of osteoarthritis.

PURPOSE

We present the first meta-analysis reporting on the development and progression of osteoarthritis after ACL injury at a minimum mean follow-up of 10 years, using a single and widely accepted radiologic classification, the Kellgren & Lawrence classification.

STUDY DESIGN

Meta-analysis.

METHOD

Articles were included for systematic review if they reported radiologic findings of ACL-injured knees and controls using the Kellgren & Lawrence classification at a minimum mean follow-up period of 10 years. Appropriate studies were then included for meta-analysis.

RESULTS

Nine studies were included for systematic review, of which 6 studies were further included for meta-analysis. One hundred twenty-one of 596 (20.3%) ACL-injured knees had moderate or severe radiologic changes (Kellgren & Lawrence grade III or IV) compared with 23 of 465 (4.9%) uninjured ACL-intact contralateral knees. After ACL injury, irrespective of whether the patients were treated operatively or nonoperatively, the relative risk (RR) of developing even minimal osteoarthritis was 3.89 (P < .00001), while the RR of developing moderate to severe osteoarthritis (grade III and IV) was 3.84 (P < .0004). Nonoperatively treated ACL-injured knees had significantly higher RR (RR, 4.98; P < .00001) of developing any grade of osteoarthritis compared with those treated with reconstructive surgery (RR, 3.62; P < .00001). Investigation of progression to moderate or severe osteoarthritis (grade III or IV only) after 10 years showed that ACL-reconstructed knees had a significantly higher RR (RR, 4.71; P < .00001) compared with nonoperative management (RR, 2.41; P = .54). It was not possible to stratify for return to sports among the patients undergoing ACL reconstruction.

CONCLUSION

Results support the proposition that ACL injury predisposes knees to osteoarthritis, while ACL reconstruction surgery has a role in reducing the risk of developing degenerative changes at 10 years. However, returning to sports activities after ligament reconstruction may exacerbate the development of arthritis.

Long-term follow-up of ACL reconstruction with hamstring autograft

PURPOSE

To investigate the differences in the incidence and severity of knee osteoarthritis (OA), joint space narrowing, knee laxity, and knee flexion and extension strength between an anterior cruciate ligament (ACL)-reconstructed knee and the contralateral non-reconstructed limb.

METHODS

Retrospective case series of patients from a single surgeon that had an ACL reconstruction with a semitendinosus/gracilis autograft more than 12 years ago. Outcome measures included radiographic analysis, International Knee Documentation Committee Subjective Knee Evaluation Form (IKDC), KT-1000, Tegner Activity Level Scale, Lysholm Knee Score, ACL quality of life score (ACL-QOL) and knee flexor/extensor strength.

RESULTS

Seventy-four patients consented and sixty-eight (43 male, 25 female) were included for analysis. Average age (SD) at the time of surgery was 31.2 (±9.1) years. At follow-up of 14.6 (1.9) years, 9% had re-ruptured their ACL, whereas 5% ruptured the contralateral ACL. Reconstructed knees had a greater incidence and severity of OA (P < 0.01). Medial meniscus surgery was a strong predictor of OA. Seventy-five per cent scored a normal or nearly normal knee on the IKDC. The mean Lysholm score was 75.8% and Tegner Activity Level Scale scores decreased (P < 0.001) from the time of surgery. Knee extension strength was greater in the contralateral knee at speeds of 60°/s (P = 0.014) and 150°/s (P = 0.012).

CONCLUSIONS

Reconstructed knees have a greater incidence and severity of OA than non-reconstructed knees, which suggests degenerative changes are secondary to ACL rupture. Medial meniscus surgery is a strong predictor of OA. Despite this, 75% of patients reported good outcomes.

Does ACL reconstruction alter natural history?: A systematic literature review of long-term outcomes

BACKGROUND

Anterior cruciate ligament (ACL) injury can lead to tibiofemoral instability, decreased functional outcomes, and degenerative joint disease. It is unknown whether ACL reconstruction alters this progression at long-term follow-up.

METHODS

A systematic literature review of the long-term results (minimum follow-up, more than ten years) after operative intra-articular reconstruction of ACL injuries and after nonoperative management was performed to compare (1) knee stability on physical examination, (2) functional and patient-based outcomes, (3) the need for further surgical intervention, and (4) radiographic outcomes. After application of selection criteria, forty patient cohorts with a mean of 13.9 ± 3.1 years of postoperative follow-up were identified. Twenty-seven cohorts containing 1585 patients had undergone reconstruction, and thirteen containing 685 patients had been treated nonoperatively.

RESULTS

Comparison of operative and nonoperative cohorts revealed no significant differences in age, sex, body mass index, or rate of initial meniscal injury (p > 0.05 for all). Operative cohorts had significantly less need for further surgery (12.4% compared with 24.9% for nonoperative, p = 0.0176), less need for subsequent meniscal surgery (13.9% compared with 29.4%, p = 0.0017), and less decline in the Tegner score (-1.9 compared with -3.1, p = 0.0215). A difference in pivot-shift test results was observed (25.5% pivot-positive compared with 46.6% for nonoperative) but did not reach significance (p = 0.09). No significant differences were seen in outcome scores (Lysholm, International Knee Documentation Committee [IKDC], or final Tegner scores) or the rate of radiographically evident degenerative joint disease (p > 0.05 for all).

CONCLUSIONS

At a mean of 13.9 ± 3.1 years after injury, the patients who underwent ACL reconstruction had fewer subsequent meniscal injuries, less need for further surgery, and significantly greater improvement in activity level as measured with the Tegner score. There were no significant differences in the Lysholm score, IKDC score, or development of radiographically evident osteoarthritis.

Long-term failure of anterior cruciate ligament reconstruction

PURPOSE

The aim of this study was to review and describe the cumulative incidence of anterior cruciate ligament (ACL) graft rupture and/or clinical objective failures at greater than 10 years after ACL reconstruction.

METHODS

A PubMed search was performed to identify and systematically evaluate all studies performed between 1980 and 2012 with clinical outcomes after intra-articular, non-artificial ACL reconstruction and minimum 10-year follow-up. Studies reporting standardized surgical technique, ACL graft rupture, and objective International Knee Documentation Committee (IKDC) grade or ligament stability examination were included for analysis. After we first identified patients with graft rupture, clinical failure was further identified as 1 or more of the following: overall IKDC objective score of C or D, IKDC grade C or D pivot shift (i.e., >2+ or pivot shift), IKDC grade C or D Lachman examination, and/or abnormal KT arthrometer (MEDmetric, San Diego, CA) measurement (i.e., >5 mm). For this study, cumulative ACL failure rates were defined as the sum of both clinical failures and ACL graft ruptures.

RESULTS

After review and exclusion of 625 references, 14 studies were identified for subsequent review. At longer than 10 years' clinical follow-up, the reported ACL graft rupture rate was 6.2% (173 of 2,782) (range, 0% to 13.4%) and clinical failure occurred in approximately 10.3% (158 of 1,532) (range, 1.9% to 25.6%). The overall cumulative ACL failure rate was 11.9% (range, 3.2% to 27%).

CONCLUSIONS

At least 1 in 9 patients undergoing ACL reconstruction will have rerupture or clinical failure at long-term follow-up.

LEVEL OF EVIDENCE

Level IV, systematic review of Level II and IV studies.

Return to play following ACL reconstruction: survey among experienced arthroscopic surgeons (AGA instructors)

PURPOSE

There is a lack of consensus regarding appropriate criteria attesting patient's unrestricted sports activities after ACL reconstruction. The purpose of this study was to perform a survey among experienced arthroscopic surgeons regarding their return to play guidelines in these patients.

METHODS

A six-item questionnaire was distributed among experienced arthroscopic surgeons (instructors of the German speaking society of arthroscopy, AGA). Study participants were asked to choose from multiple choice answers and had the possibility answering in an open discussion field.

RESULTS

The response rate of the survey was 85.7 %. A total of 83.5 % used autologous hamstring grafts for ACL reconstruction in athletes followed by BPTB (37.2 %) and quadriceps tendon graft (12 %). Approximately 63.5 % recommended a time point later than 6 months allowing return to play after ACL reconstruction in the athlete (after 4 and 6 months 2.3 and 35.3 %, respectively). 76.6 % recommended starting with sports specific rehabilitation after 4 months (21.6 % after 6 months). The most frequent criterion (multiple answers) to allow return to play was negative Lachman test (81.7 % positive answers) followed by free range of motion (78.4 %), negative pivot shift (60.1 %), anterior drawer (45.4 %), proprioception test (43.1 %), muscular strength analysis (40.8 %), single-leg hop jump test (39.0 %), KT 1000 measurement (16.1 %), and MRI (4.1 %). Of the surgeons 85.8 % did not use any of the given scores as criterion to allow return to competitive sports (subjective IKDC score 10.6 %, Lysholm score 8.3 %, objective IKDC score 7.4 %, Tegner activity scale 3.7 %).

CONCLUSION

In conclusion, the majority of surgeons do not consider muscle function, jump tests, alignment tests, and proprioception as relevant return to sports criterion. However, these are two crucial parameters for return to sports.

Double-bundle versus single-bundle anterior cruciate ligament reconstructions: a prospective, randomized study with 2-year follow-up

This prospective, randomized study was conducted to compare the short-term results of arthroscopic double-bundle with single-bundle anterior cruciate ligament (ACL) reconstruction. One hundred and eight patients with a symptomatic ACL rupture were randomized to either double-bundle (Group DB) or single-bundle (Group SB) ACL reconstruction. Follow-up was conducted at 6, 12, 18 and 24 months postoperatively. At the 24-month follow-up, 94 of the 108 patients (87%) were available for evaluation. The rotational stability, as evaluated by pivot shift test, was significantly superior in the Group DB to that in the Group SB. No significant difference with regard to ACL revisions, total flexion work, mean peak flexion torque and extension work between the groups was detected. There was no significant difference between the groups in terms of the Tegner activity score, the knee injury and osteoarthritis outcome score, the Lysholm functional score, anterior knee pain or mobility, subjective knee function. In addition, no significant difference in laxity on the Lachman test or the KT-1000 maximum manual force test was investigated. All the results were significantly more satisfactory at each follow-up period than preoperatively, in both groups. Both SB- and DB-ACL reconstruction resulted in satisfactory subjective outcome and objective stability. Both these techniques can therefore be considered as suitable alternatives for ACL reconstruction. Moreover, as it seems to be according to the pivot shift test, the risk for the development of degenerative changes of the knee joint in a long run could be smaller in the Group DB.

The prevalence of patellofemoral osteoarthritis 12 years after anterior cruciate ligament reconstruction

PURPOSE

To investigate the prevalence of patellofemoral osteoarthritis (OA) and to explore the association between radiographic patellofemoral OA and symptoms and function 12 years after anterior cruciate ligament (ACL) reconstruction.

METHODS

The study participants (n = 221) were consecutively included at the time of an ACL reconstruction in the period from 1990 to 1997. Knee laxity (KT-1000), isokinetic quadriceps strength, triple jump, stair hop, and the Cincinnati knee score were measured 6 months, 1 year, 2 years, and 12 years after surgery. At the 12-year follow-up, visual analogue scale for pain, the Knee injury and Osteoarthritis Outcome Score, the Tegner activity scale, and radiographic examination (Kellgren and Lawrence score) were added. To analyse the association between patellofemoral OA, symptoms, and function, binary regression analyses presenting odds ratios and 95 % confidence intervals were used. The analyses were adjusted for age, gender, and body mass index.

RESULTS

One hundred and eighty-one of the 221 subjects (82 %), including 76 females (42 %) and 105 males (58 %), were evaluated at the 12.3 ± 1.2-year follow-up. Mean age at the follow-up was 39.1 ± 8.7 years. Additional meniscal or chondral injuries at the time of reconstruction or during the follow-up period were detected in 116 subjects (64 %). Radiographic patellofemoral OA was found in 48 subjects (26 %), including 3 subjects with isolated patellofemoral OA (1.5 %). Those with patellofemoral OA were older, had more tibiofemoral OA, and had significantly more symptoms and impaired function compared with those without patellofemoral OA.

CONCLUSIONS

Patellofemoral OA was found in 26 % 12 years after ACL reconstruction. Patellofemoral OA was associated with increased age, tibiofemoral OA, increased symptoms, and reduced function. It is of clinical importance to include functional and radiographic assessment of the patellofemoral joint in the examination of long-term consequences following an ACL reconstruction.

The role of ACL injury in the development of posttraumatic knee osteoarthritis

Acute anterior cruciate ligament (ACL) tears are most frequently sustained by young, physically active individuals. ACL injuries are seen at high incidence in adolescents and young adults performing sports and occupational activities that involve pivoting. Young women participating in pivoting sports have a 3 to 5 times higher risk of ACL injury than men. Studies show that ACL injury increases osteoarthritis (OA) risk with symptomatic OA appearing in roughly half of individuals 10-15 years later. Because the majority of patients sustaining acute ACL tears are younger than 30, this leads to early onset OA with associated pain and disability during premium work and life growth years between ages 30 and 50. Effective strategies to prevent ACL injury and to reduce subsequent OA risk in those sustaining acute ACL tears are needed.

Single-bundle anterior cruciate ligament reconstruction in active young men using bone-tendon achilles allograft versus free tendon achilles allograft

PURPOSE

The purpose was to prospectively compare the outcomes of anterior cruciate ligament (ACL) reconstruction using bone-tendon Achilles allograft with those of free tendon Achilles allograft in 2 groups of active young men.

METHODS

We enrolled 72 subjects in the study. Of these, 33 subjects who had ACL reconstruction with Achilles allograft with calcaneal bone block on its end (group I) and 34 who had ACL reconstruction with free tendon Achilles allograft (group II) were followed up for a minimum of 2 years. The Lachman test, pivot-shift test, and 1-leg hop test were evaluated at the last follow-up. The International Knee Documentation Committee classification, Lysholm score, and side-to-side difference were assessed preoperatively and at the last follow-up. The Tegner activity scale was evaluated before injury and at the last follow-up.

RESULTS

The mean follow-up period was 30.9 months (range, 26 to 38 months). At the last follow-up, there were no statistically significant differences between the 2 groups for the Lachman test, pivot-shift test, 1-leg hop test, International Knee Documentation Committee classification, Lysholm score, and side-to-side difference (P > .05). Three subjects in group I and three in group II showed an activity level 2 steps below the preinjury activity level. The rest of the subjects returned to the preinjury activity level or showed a level 1 step below the preinjury activity level.

CONCLUSIONS

There were no significant differences in clinical outcomes of ACL reconstructions using Achilles allograft between the bone-tendon group and the free tendon group in active young men. Free tendon Achilles allograft may be considered an option for ACL reconstruction.

LEVEL OF EVIDENCE

Level II, therapeutic study, randomized controlled trial.

Aseptically processed and chemically sterilized BTB allografts for anterior cruciate ligament reconstruction: a prospective randomized study

PURPOSE

To compare the clinical outcomes of bone-patellar tendon-bone (BTB) allografts processed via a novel sterilization system with the traditional aseptically processed BTB allografts for anterior cruciate ligament (ACL) reconstruction.

METHODS

A total of 67 patients undergoing ACL reconstruction at 6 independent investigation sites were randomized into one of two intervention groups, BioCleanse-sterilized or aseptic BTB allografts. Inclusion criteria included an acute, isolated, unilateral ACL tear, and exclusion criteria included prior ACL injury, multi-ligament reconstruction, and signs of degenerative joint disease. Post-op examiners and patients were blinded to graft type. Patients were evaluated at 6, 12, and 24 months. Clinical outcomes were compared using the IKDC, a KT-1000 knee arthrometer, level of effusion, and ranges of motion (ROM).

RESULTS

After randomization, 24 patients received aseptic BTB allografts and 43 patients received BioCleanse-sterilized allografts. Significant improvement in IKDC scores (P < 0.0001) as well as KT-1000 results (P < 0.0001) was noted over the 24-month period for both groups. IKDC or KT-1000 results were not significantly different between groups at any time point. Active flexion ROM significantly improved from pre-op to 24-month follow-up (P < 0.0001) with no difference between groups at any time point. Active extension ROM did not differ significantly between the two groups.

CONCLUSIONS

These results indicate that the sterilization process, BioCleanse, did not demonstrate a statistical difference in clinical outcomes for the BTB allograft at 2 years. The BioCleanse process may provide surgeons with allografts clinically similar to aseptically processed allograft tissue with the benefit of addressing donor-to-recipient disease.

LEVEL OF EVIDENCE

II.

The effect of graft tissue on anterior cruciate ligament outcomes: a multicenter, prospective, randomized controlled trial comparing autograft hamstrings with fresh-frozen anterior tibialis allograft

PURPOSE

To compare the results and outcome of anterior cruciate ligament (ACL) reconstruction using autogenous hamstring tendon versus fresh-frozen allograft anterior tibialis tendon.

METHODS

A prospective randomized study was conducted from September 2002 to October 2006. We randomized 147 patients to undergo ACL reconstruction with either autogenous hamstring or fresh-frozen allograft anterior tibialis tendon. Of these patients, 102 (69%) completed a minimum of 2 years' follow-up. There were 54 patients in the hamstring group (73% of those originally enrolled in the group) and 48 patients in the allograft group (66%). All patients underwent standardized subjective and objective evaluation with functional outcome assessments (International Knee Documentation Committee [IKDC]), and standardized radiographs were also obtained.

RESULTS

The mean age was 32.0 years for the autograft group and 33.3 years for the allograft group. There was no difference in stability between the 2 groups (P > .05). The mean IKDC subjective score was 91.0 for the autograft group and 90.9 for the allograft group (P > .05). The functional IKDC scores for the autograft group were normal in 46 patients (85%), nearly normal in 7 patients (13%), and severely abnormal in 1 patient. For the allograft group, the functional IKDC scores were normal in 43 patients (90%) and nearly normal in 5 (10%) (P > .05). There were 4 reoperations in the allograft group and 3 reoperations in the autograft group. No patient underwent revision ACL surgery or planned to undergo revision surgery because of instability in either group during the study period despite the 1 patient in the autograft group with a pivot shift and a maximum manual KT measurement (MEDmetric, San Diego, CA) of 5 mm.

CONCLUSIONS

The use of fresh-frozen anterior tibialis allograft (non-treated) for ACL reconstruction produced similar subjective and functional outcomes at 24 months' minimal follow-up compared with patients undergoing ACL reconstruction with autograft hamstring tendon.

LEVEL OF EVIDENCE

Level II, prospective comparative study.

A tale of 10 European centres - 2010 APOSSM travelling fellowship review in ACL surgery

The purpose of ESSKA- APOSSM Travelling fellowship is to better understand the epidemiology, management and surgical techniques for sports across continents. There has been a progressive evolution in ACL reconstruction and there is variation in technique in ACL reconstruction amongst the most experienced surgeons in different continents. During this one month fellowship, we saw various ACL reconstruction techniques using different graft sources, with a variety of graft fixation methods, with the common aim of recreating an anatomical ACL reconstruction.

Treatment of meniscus tears during anterior cruciate ligament reconstruction

PURPOSE

To define the incidence of meniscectomy, meniscus repair, and meniscus tears left in situ during anterior cruciate ligament (ACL) reconstruction.

METHODS

A systematic search of PubMed and 7 sports medicine journal databases was performed to determine the treatment of meniscus tears during ACL reconstruction. Inclusion criteria were English language, publication in the last 10 years, clinical trials, all evidence levels, and skeletally mature or immature knees. Exclusion criteria were revision ACL reconstruction, concomitant ligament reconstruction, and studies with exclusion or inclusion criteria regarding meniscus surgery during ACL reconstruction.

RESULTS

Of 634 articles identified, 159 met the inclusion criteria, encompassing 19,531 patients. There were 11,711 meniscus tears; they were treated by meniscectomy in 65% (7,621 tears), treated by repair in 26% (3,022 tears), or left in situ in 9% (1,068 tears). Only 19 studies analyzed the treatment of meniscus tears according to the tibiofemoral compartment. These reported medial compartment tears were treated by meniscectomy in 63%, treated by repair in 27%, and left in situ in 9%. Lateral compartment tears were treated by meniscectomy in 71%, treated by repair in 14%, and left in situ in 14%. Only 24 studies identified the type of meniscus repair procedure performed. In 33 studies (21%) repair was performed more frequently than meniscectomy.

CONCLUSIONS

Meniscectomy is performed 2 to 3 times more frequently than meniscus repair during ACL reconstruction. We were unable to analyze the effect of the location and type of meniscus tear, sex, age, or chronicity of injury on the treatment of meniscus tears. The number of potentially repairable meniscus tears that were treated by resection could not be identified.

CLINICAL RELEVANCE

This study found that meniscectomy was performed in 65% of meniscus tears. This is concerning because studies have shown that, regardless of knee stability obtained after ACL reconstruction, meniscectomy accelerates degenerative joint changes.

LEVEL OF EVIDENCE

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

Factors used to determine return to unrestricted sports activities after anterior cruciate ligament reconstruction

PURPOSE

Anterior cruciate ligament (ACL) reconstruction is commonly performed in athletes, with the goal of return to sports activities. Unfortunately, this operation may fail, and the rates of either reinjuring an ACL-reconstructed knee or sustaining an ACL rupture to the contralateral knee range from 3% to 49%. One problem that exists is a lack of information and consensus regarding the appropriate criteria for releasing patients to unrestricted sports activities postoperatively. The purpose of this study was to determine the published criteria used to allow athletes to return to unrestricted sports activities after ACL reconstruction.

METHODS

A systematic search was performed to identify the factors investigators used to determine when return to athletics was allowed after primary ACL reconstruction. Inclusion criteria were English language, publication within the last 10 years, clinical trial, all adult patients, primary ACL reconstruction, original research investigation, and minimum 12 months' follow-up.

RESULTS

Of 716 studies identified, 264 met the inclusion criteria. Of these, 105 (40%) failed to provide any criteria for return to sports after ACL reconstruction. In 84 studies (32%) the amount of time postoperatively was the only criterion provided. In 40 studies (15%) the amount of time along with subjective criteria were given. Only 35 studies (13%) noted objective criteria required for return to athletics. These criteria included muscle strength or thigh circumference (28 studies), general knee examination (15 studies), single-leg hop tests (10 studies), Lachman rating (1 study), and validated questionnaires (1 study).

CONCLUSIONS

The results of this systematic review show noteworthy problems and a lack of objective assessment before release to unrestricted sports activities. General recommendations are made for quantification of muscle strength, stability, neuromuscular control, and function in patients who desire to return to athletics after ACL reconstruction, with acknowledgment of the need for continued research in this area.

LEVEL OF EVIDENCE

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

Greater than 10-year results of red-white longitudinal meniscal repairs in patients 20 years of age or younger

BACKGROUND

A prospective longitudinal investigation was conducted to determine the long-term outcome of single longitudinal meniscal repairs extending into the central avascular region in patients aged 20 years or younger.

PURPOSE

To determine the long-term success rate and reoperation rate of meniscal repairs extending into the avascular zone.

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

Thirty-three meniscal repairs were performed using an inside-out multiple vertical divergent suture technique. A concomitant anterior cruciate ligament reconstruction was done in 18 patients. The mean follow-up was 16.8 years (range, 10.1-21.9 years). The long-term success rate was determined in 29 repairs (88%) by the presence of normal or nearly normal parameters from 2 validated knee rating systems, assessment of magnetic resonance imaging and weightbearing posteroanterior radiographs by independent physicians, and follow-up arthroscopy when required. A 3 Tesla magnetic resonance imaging scanner with cartilage-sensitive pulse sequences was used, and T2 mapping was performed. A comparison was made between the short-term (mean, 4 years) and long-term outcomes.

RESULTS

Eighteen (62%) of the meniscal repairs had normal or nearly normal characteristics in all of the parameters assessed. Six repairs (21%) required partial arthroscopic resection, 2 had loss of joint space on radiographs, and 3 that were asymptomatic failed according to magnetic resonance imaging criteria, for a total of 11 documented failures (38%). There was no significant difference in the mean articular cartilage T2 scores in the healed menisci between the involved and contralateral tibiofemoral compartments in the same knee. There were no significant differences between short- and long-term evaluations for pain, swelling, jumping, patient knee condition rating, or the overall Cincinnati rating score.

CONCLUSIONS

A chondroprotective joint effect was demonstrated in the healed menisci repairs, which warrants the procedure in select patients. The long-term evaluation of the anterior cruciate ligament-reconstructed knees with concurrent successful meniscal repairs demonstrated a low rate of radiographic arthritis.

Anterior cruciate ligament allograft surgery: underreporting of graft source, graft processing, and donor age

BACKGROUND

There has been much controversy regarding the effects of sterilization techniques and graft history on the structural integrity of allograft ligaments used in reconstruction of the anterior cruciate ligament. The purpose of this review was to comprehensively examine anterior cruciate ligament allograft studies published in the last decade to evaluate the extent to which tissue source, tissue processing techniques, and donor age are reported.

METHODS

The authors reviewed 202 articles published from 1999 through November 2009, of which 68 retrospective, prospective, biomechanical, and histology studies evaluating 4689 allografts were included.

RESULTS

The majority of studies do not accurately report key elements of graft history including tissue bank, processing or sterilization technique, or donor age. Underreporting was particularly prominent in clinical studies as compared with basic science studies. Limited reporting of allograft processing, allograft source, and donor age raises serious questions regarding the generalizability of published studies of allograft tissue for anterior cruciate ligament reconstruction. Conclusion/

CLINICAL RELEVANCE

Orthopaedic surgeons who use allograft tissue must understand the tissue treatments being used (ie, preservation methods, chemical and sterilization processes) to best inform their patients regarding the risks, benefits, and long-term outcomes when such tissues are used. A complete understanding of the implanted tissue, as well as surgeon and recipient demographics, is necessary to ensure appropriate and predictable long-term outcomes.

Comparison of the hospital cost of autograft versus allograft soft-tissue anterior cruciate ligament reconstructions

PURPOSE

The purpose of this study was to compare the cost of anterior cruciate ligament (ACL) reconstruction with either hamstring autograft or tibialis anterior allograft.

METHODS

The hospital cost and charge data for patients undergoing ACL reconstruction by a single surgeon using either tibialis anterior tendon allograft (n = 49) or hamstring tendon autograft (n = 49) were retrospectively obtained and analyzed. Costs were broken down into several categories for comparison. The surgeon, operative technique, and surgical team were controlled.

RESULTS

The mean total hospital cost for ACL reconstruction was $4,072.02 for autograft and $5,195.19 for allograft, for a difference of $1,123.16 (P < .0001). The only other statistically significant differences found were in the costs of the supplies ($1,296.07 more for allograft, P < .0001) and the recovery room ($82.54 more for the autograft, P < .01). No statistically significant differences were found in the costs for the operating room, anesthesia, or pharmacy.

CONCLUSIONS

In the setting of a high-volume, experienced surgical team, the additional cost of using an allograft for ACL reconstruction was not offset by the decreased operative and recovery room costs.

LEVEL OF EVIDENCE

Level III, retrospective comparative study.

Deltoid ligament reconstruction: a novel technique with biomechanical analysis

BACKGROUND

Deltoid ligament insufficiency has been shown to decrease tibiotalar contact area and increase peak pressures within the lateral ankle mortise. This detrimental effect may create an arthritic ankle joint if left unresolved. Reconstructive efforts thus far have been less than satisfactory. We describe a novel technique that reconstructs both main limbs of the deltoid ligament in anatomic orientation while providing secure graft fixation.

MATERIALS AND METHODS

Six pairs of fresh frozen cadaveric lower extremities were utilized. Matched right and left lower limbs (one pair) were allocated either to a deltoid reconstruction group or an intact deltoid group. The anterior tibial tendon was chosen as the graft for ligament reconstruction, and was harvested from the ipsilateral specimen. Tunnels were created in the distal tibia at the deltoid origin, and at the talus (deep) and calcaneus (superficial) deltoid insertions. Following measurement, the graft was cut to the appropriate size and endobuttons weaved into both tendon ends. The graft ends were passed through the talus and calcaneus respectively. The residual graft loop was then routed through the tibial tunnel and secured proximally with a cancellous screw post and spiked washer. Following specimen mounting, a multiaxis testing apparatus with three separate motors allowed three planes (dorsiflexion/plantarflexion; inversion/eversion; and internal/external rotation) of motion. Angular rotations and linear translations of the tibia in the X-Y-Z directions were measured for a given torque in external/internal rotation, dorsiflexion/plantarflexion, or eversion/inversion, under a constant velocity of 2 degrees per second. Testing consisted of a 2 Nm preload for 20 cycles in internal rotation/external rotation and inversion/eversion prior to data collection of 10 cycles at this level of torque. Similarly, a preload of 1 Nm for 20 cycles was used in dorsiflexion/plantarflexion prior to data collection of 10 cycles at this torque level. Data were collected in the control specimens (the matched contralateral extremity) with the deltoid ligament intact, and following complete sectioning of the ligament complex (both bundles).

RESULTS

Angular displacement at a 2 Nm level torque was significantly greater in the sectioned group compared to the deltoid reconstruction group in external rotation and eversion (p = 0.006 and p = 0.017 respectively). There was no statistical difference in angular displacement between the deltoid intact and reconstructed group in external rotation and eversion when tested at 2 Nm of torque (p = 0.865 and p = 0.470, respectively). The stiffness of the reconstruction was 136.4 +/- 40.2% compared to the intact ligament. Stiffness data were statistically insignificant in both plantar flexion and dorsiflexion between the reconstructed and sectioned groups (p = 0.050 and p = 0.126).

CONCLUSION

The described reconstruction technique under low torque was able to restore eversion and external rotation stability to the talus, which was statistically similar to the intact deltoid ligament. This novel technique developed its strength not only from the anatomic orientation of the reconstructed ligament, but the strength of the components chosen to fix the tendon graft to the bone.

CLINICAL RELEVANCE

This utilitarian reconstruction may be incorporated into total ankle arthroplasty, triple arthrodesis, and sports injuries to re-establish lost medial stability.

Anterior cruciate ligament reconstruction with LARS artificial ligament: a multicenter study with 3- to 5-year follow-up

PURPOSE

The aim of this multicenter study was to evaluate the clinical outcome of anterior cruciate ligament (ACL) reconstruction by use of the Ligament Advanced Reinforcement System (LARS) artificial ligament (Surgical Implants and Devices, Arc-sur-Tille, France) with 3- to 5-year follow-up.

METHODS

From August 2004 to July 2006, 159 patients with ACL rupture underwent arthroscopic ACL reconstruction with LARS artificial ligament at 4 orthopaedic sports medicine centers in China. They were retrospectively followed up for 50 +/- 6 months (range, 36 to 62 months). Outcome assessment included physical examination, KT-1000 arthrometer testing (MEDmetric, San Diego, CA), magnetic resonance imaging, radiography, Lysholm score, Tegner score, International Knee Documentation Committee score, and subjective satisfaction rate. Quadriceps and hamstring isokinetic strength was evaluated in 68 patients.

RESULTS

The side-to-side difference in anterior translation (injured side - uninjured side) measured by KT-1000 arthrometer was 1.5 +/- 1.6 mm (range, -1 to 7 mm) postoperatively, and knee stability was significantly improved compared with preoperative data (P < .0001). Quadriceps and hamstring isokinetic peak torque of the injured limb expressed as a percentage of the contralateral limb was 93.6 +/- 10.7 and 95.8 +/- 12.0, respectively. The Lysholm score improved from 65.1 +/- 12.3 points (range, 30 to 95 points) preoperatively to 94.5 +/- 7.0 points (range, 65 to 100 points) postoperatively (P < .0001). The Tegner score improved from 3.1 +/- 1.6 (range, 0 to 6) preoperatively to 6.1 +/- 1.5 (range, 1 to 9) postoperatively (P < .0001). According to the International Knee Documentation Committee score, 94% of patients were graded A or B at last follow-up. Ninety-three percent of patients were very satisfied or satisfied with their outcome. LARS artificial ligament rupture occurred in 3 patients; knee synovitis developed in 1 of these patients.

CONCLUSIONS

ACL reconstruction with LARS artificial ligament used in patients with the ACL stump preserved in the acute and chronic phases has a very good outcome at mean of 50 months' follow-up. The overall complication rate for ACL reconstruction with LARS artificial ligament is 5.7%, and knee synovitis developed in only 1 case.

LEVEL OF EVIDENCE

Level IV, therapeutic case series.

Implantation increases tensile strength and collagen content of self-assembled tendon constructs

Tissue-engineered tendons, derived from an autologous cell source, have the potential to provide an ideal replacement graft that is biologically compatible and has the ability to adapt to the specific mechanical requirements of the in vivo environment. Scaffold-free tendon constructs have been successfully engineered in vitro. However, when compared against native tendons the constructs demonstrate both a lower tensile strength and collagen content. We hypothesized that the in vitro environment lacks certain environmental stimuli and that implantation in vivo would facilitate the maturation of engineered tissues. Using primary Achilles tendon fibroblasts from adult rats, self-organizing constructs were created in vitro. Tendon constructs were implanted subcutaneously into the groins of adult rats for 4 wk, while controls remained in vitro. Implanted constructs increased in stiffness by three orders of magnitude when compared with the in vitro controls (7,500 vs. 22.3 kPa). This increase in tangent modulus correlated with a significant increase in collagen content, as measured by hydroxyproline concentration, from 3.9% for the in vitro controls to 22.7% in the in vivo conditioned group. In addition, collagen fiber diameter increased from 22.0 to 75.4 nm as a result of in vivo implantation. The tensile strength and collagen content of in vivo conditioned constructs were similar to the values determined for neonatal rat tibialis anterior tendons.

Primary ACL reconstruction using allograft tissue

While bone-patellar tendon-bone (BPTB) autograft continues to be the "gold standard" and most popular graft choice for primary anterior cruciate ligament (ACL) reconstructions, the use of allograft tissues in ACL reconstruction has steadily increased over the last 2 decades. Advantages of allograft include a lack of donor-site morbidity, unlimited available sizes, shorter operative times, availability of larger grafts, smaller incisions, improved cosmesis, lower incidence of postoperative arthrofibrosis, faster immediate postoperative recovery, and less postoperative pain. Disadvantages include the potential for disease transmission and prolonged graft healing. Presented in this article are 2 techniques used at the authors' institution for primary ACL reconstruction with allograft. With the proper indications, knowledge of graft preparation and handling, and technique, allograft tissues in ACL reconstructions can provide the surgeon with clinical results equal to those of autograft reconstructions.

Knee osteoarthritis after anterior cruciate ligament injury: a systematic review

BACKGROUND

This is a systematic review of studies on the prevalence of osteoarthritis in the tibiofemoral joint more than 10 years after an anterior cruciate ligament injury, the radiologic classification methods used, and risk factors for development of knee osteoarthritis.

METHODS

A systematic search was performed in PubMed, EMBASE, and AMED. Inclusion criteria were studies involving patients with anterior cruciate ligament injury, either isolated or combined with medial collateral ligament or meniscal injury and either surgically or nonsurgically treated, and a minimum 10-year follow-up with radiologic assessment. Methodological quality was evaluated using a modified version of the Coleman methodology score.

RESULTS

Seven prospective and 24 retrospective studies were included. The mean modified Coleman methodology score was 52 of 90. Reported prevalence of knee osteoarthritis for subjects with isolated anterior cruciate ligament injury was between 0% and 13%. For subjects with anterior cruciate ligament and additional meniscal injury, the prevalence varied between 21% and 48%. Seven different radiologic classification systems were used in the studies. Only 3 studies reported reliability results for the radiologic assessments. The most frequently reported risk factor for development of knee osteoarthritis was meniscal injury.

CONCLUSION

This systematic review suggests that the prevalence rates of knee osteoarthritis after anterior cruciate ligament reconstruction reported by previous reviews have been too high. The highest rated studies reported low prevalence of knee osteoarthritis for individuals with isolated anterior cruciate ligament injury (0%-13%) and a higher prevalence of knee osteoarthritis for subjects with combined injuries (21%-48%). Overall, the modified Coleman methodology score was low for the included studies. No universal methodological radiologic classification method exists, making comparisons of the studies and stating firm conclusions on the prevalence of knee osteoarthritis more than 10 years after anterior cruciate ligament injury difficult.