Five-year clinical outcomes of a randomized trial of anterior cruciate ligament treatment strategies: an evidence-based practice paper

Clinical validation of fully automated laminar knee cartilage transverse relaxation time (T2) analysis in anterior cruciate ligament (ACL)-injured knees- on behalf of the osteoarthritis (OA)-Bio consortium

Background

Magnetic resonance imaging (MRI) cartilage transverse relaxation time (T2) reflects cartilage composition, mechanical properties, and early osteoarthritis (OA). T2 analysis requires cartilage segmentation. In this study, we clinically validate fully automated T2 analysis at 1.5 Tesla (T) in anterior cruciate ligament (ACL)-injured and healthy knees.

Methods

We studied 71 participants: 20 ACL-injured patients with, and 22 without dynamic knee instability, 13 with surgical reconstruction, and 16 healthy controls. Sagittal multi-echo-spin-echo (MESE) MRIs were acquired at baseline and 1-year follow-up. Femorotibial cartilage was segmented manually; a convolutional neural network (CNN) algorithm was trained on MRI data from the same scanner.

Results

Dice similarity coefficients (DSCs) of automated versus manual segmentation in the 71 participants were 0.83 (femora) and 0.89 (tibiae). Deep femorotibial T2 was similar between automated (45.7±2.6 ms) and manual (45.7±2.7 ms) segmentation (P=0.828), whereas superficial layer T2 was slightly overestimated by automated analysis (53.2±2.2 vs. 52.1±2.1 ms for manual; P<0.001). T2 correlations were r=0.91-0.99 for deep and r=0.86-0.97 for superficial layers across regions. The only statistically significant T2 increase over 1 year was observed in the deep layer of the lateral femur [standardized response mean (SRM) =0.58 for automated vs. 0.52 for manual analysis; P<0.001]. There was no relevant difference in baseline/longitudinal T2 values/changes between the ACL-injured groups and healthy participants, with either segmentation method.

Conclusions

This clinical validation study suggests that automated cartilage T2 analysis from MESE at 1.5T is technically feasible and accurate. More efficient 3D sequences and longer observation intervals may be required to detect the impact of ACL injury induced joint instability on cartilage composition (T2).

Impact of anterior cruciate ligament surgery on the development of knee osteoarthritis: A systematic literature review and meta-analysis comparing non-surgical and surgical treatments

Introduction

Context: The development of knee osteoarthritis (OA) after anterior cruciate ligament (ACL) injury is now widely recognized. The impact of surgical or non-surgical management on the development of post-traumatic osteoarthritis is still debated in the medical community.Here, we present a meta-analysis comparing the impact of surgical or non-surgical management of ACL injuries on the development of knee OA.

Method

A systematic literature review was conducted using data from the PubMed, EMBASE, Medline, and Cochrane libraries from February to May 2019. Only randomized clinical trials published between 2005 and 2019 with a non-surgical group and a surgical group were included to explore the onset or progression of knee OA after ACL injury. Trials had to have at least one radiographic endpoint (Kellgren-Lawrence scoring system). Heterogeneity was assessed using the Cochrane's Q and I2 statistical methods.

Results

Only three randomized controlled trials met the inclusion criteria and were selected for meta-analysis. Of the 343 injured knees included in the studies, 180 underwent ACL reconstruction and 163 underwent non-surgical treatment. The relative risk of knee osteoarthritis was higher after surgery than after non-surgical treatment (RR 1.72, CI 95% [1.18-2.53], I2 ​= ​0%).

Conclusion

The results of this meta-analysis suggest a predisposition to knee osteoarthritis after ACL reconstruction surgery compared with non-surgical management. Due to the small number of good quality studies available, further well-conducted randomised studies are needed to confirm these findings.

Positional MR imaging of normal and injured knees

OBJECTIVES

This study uses a practical positional MRI protocol to evaluate tibiofemoral translation and rotation in normal and injured knees.

METHODS

Following ethics approval, positional knee MRI of both knees was performed at 35° flexion, extension, and hyperextension in 34 normal subjects (mean age 31.1 ± 10 years) and 51 knee injury patients (mean age 36.4 ± 11.5 years, ACL tear n = 23, non-ACL injury n = 28). At each position, tibiofemoral translation and rotation were measured.

RESULTS

Normal knees showed 8.1 ± 3.3° external tibial rotation (i.e., compatible with physiological screw home mechanism) in hyperextension. The unaffected knee of ACL tear patients showed increased tibial anterior translation laterally (p = 0.005) and decreased external rotation (p = 0.002) in hyperextension compared to normal knees. ACL-tear knees had increased tibial anterior translation laterally (p < 0.001) and decreased external rotation (p < 0.001) compared to normal knees. Applying normal thresholds, fifteen (65%) of 23 ACL knees had excessive tibial anterior translation laterally while 17 (74%) had limited external rotation. None (0%) of 28 non-ACL-injured knees had excessive tibial anterior translation laterally while 13 (46%) had limited external rotation. Multidirectional malalignment was much more common in ACL-tear knees.

CONCLUSIONS

Positional MRI shows (a) physiological tibiofemoral movement in normal knees, (b) aberrant tibiofemoral alignment in the unaffected knee of ACL tear patients, and (c) a high frequency of abnormal tibiofemoral malalignment in injured knees which was more frequent, more pronounced, more multidirectional, and of a different pattern in ACL-tear knees than non-ACL-injured knees.

KEY POINTS

• Positional MRI shows physiological tibiofemoral translation and rotation in normal knees. • Positional MRI shows a different pattern of tibiofemoral alignment in the unaffected knee of ACL tear patients compared to normal control knees. • Positional MRI shows a high prevalence of abnormal tibiofemoral alignment in injured knees, which is more frequent and pronounced in ACL-tear knees than in ACL-intact injured knees.

Degenerative changes through MR cartilage mapping in anterior cruciate ligament-reconstructed knees

Background

Anterior cruciate ligament (ACL) injury increases risk for post traumatic knee osteoarthritis. ACL injury causes lack of knee stability and frequently requires ACL-reconstruction (ACLR) in order to restore functional and anatomical joint stability. Magnetic resonance imaging with T2 mapping sequence is used to quantify the amount of water content in articular cartilage hence; it is considered a better tool and more beneficial than radiographic based assessment in early detection even before being symptomatic. The aim of work is to estimate the incidence of subclinical degenerative changes that happened early in patients who underwent ACL reconstruction and to identify the correlations of T2 mapping values with patients' BMI, meniscal state/operations, ACL graft assessment and presence of ACLR related complications.

Results

The study was conducted upon 71 patients, divided into 61 anterior cruciate ligament reconstructed knees and 10 control cases using 1.5 T MRI. Assessment of cartilage sub-compartment T2 values and comparison with average normal cartilage T2 values obtained from the control group. Multiple correlations of the grade of articular cartilage degeneration within anterior cruciate ligament reconstructed knees with Body Mass Index (BMI), time of operation as well associated meniscal operations and anterior cruciate ligament graft complications.

Conclusions

Adding the T2 cartilage mapping sequence improves the ability to detect subclinical early degenerative articular cartilage changes in patients who underwent anterior cruciate ligament reconstruction, taking into consideration the relation of the patients' BMI, previous meniscal injuries/operation, ACL graft status and related graft complications with the T2 cartilage mapping values.

Knee Osteoarthritis Following Anterior Cruciate Ligament Reconstruction: Frequency, Contributory Elements, and Recent Interventions to Modify the Route of Degeneration

Half of the individuals who experience an anterior cruciate ligament reconstruction (ACLR) suffer from knee osteoarthritis (OA) 12-14 years later. Elements that make a contribution to the appearance of OA following ACLR are anomalous anterior tibial displacement and anomalous tibial rotation in the course of the stance phase of walking (exhibited in 85% of operated knees). Individuals who undergo an early ACLR (5 days on average following anterior cruciate ligament [ACL] breakage) have an inferior frequency of radiographically apparent tibiofemoral OA at 32-37 years of follow-up than individuals with ACL rupture who did not experience the procedure. Nevertheless, the percentage of symptomatic OA, radiographically apparent patellofemoral OA and knee symptoms are alike in both groups. At 15 years of follow-up, 23% of knees that experienced an anatomic ACLR suffer from OA, while this percentage augments to 44% if the ACLR was non-anatomic. Knees of individuals who experience ACLR need total knee arthroplasty at an earlier age than healthy knees. Intra-articular injections of interleukin-1 receptor antagonist and corticosteroids may reduce the risk of OA after ACLR.

Long-term quality of life, work limitation, physical activity, economic cost and disease burden following ACL and meniscal injury: a systematic review and meta-analysis for the OPTIKNEE consensus

OBJECTIVE

Determine the long-term health-related quality-of-life (HRQoL), work limitation, physical activity, health/economic cost and disease burden of traumatic ACL and/or meniscal injury. Findings will inform OPTIKNEE evidence-based consensus recommendations.

DESIGN

Random-effects meta-analysis evaluated HRQoL (SF-36/SF-12/VR-12 Physical Component Scores (PCS) and Mental Component Scores (MCS), EuroQol-5D (EQ-5D)) stratified by time postinjury, and pooled mean differences (95% CI) between ACL-injured and uninjured controls. Other outcomes were synthesised descriptively. Risk-of-bias (RoB) and certainty of evidence (Grading of Recommendations Assessment, Development and Evaluation) were assessed.

DATA SOURCES

MEDLINE, EMBASE, CENTRAL, SPORTDiscus, CINAHL searched inception: 22 November 2021.

ELIGIBILITY

Studies reporting HRQoL, work limitations, physical activity levels, health/economic costs or disease burden, ≥2 years post-ACL and/or meniscal injury.

RESULTS

Fifty studies were included (10 high-RoB, 28 susceptible-to-some-bias and 12 low-RoB). Meta-analysis (27 studies, very low certainty of evidence) estimated a pooled mean (95% CI) PCS of 52.4 (51.4 to 53.4) and MCS of 54.0 (53.0 to 55.0) 2-14 years post-ACL injury. Pooled PCS scores were worse >10 years (50.8 (48.7 to 52.9)) compared with 2-5 years (53.9 (53.1 to 54.7)) postinjury. Excluding high-RoB studies, PCS scores were worse in ACL-injured compared with uninjured controls (-1.5 (-2.9 to -0.1)). Six studies (low certainty of evidence) informed a pooled EQ-5D score of 0.83 (0.81 to 0.84). Some individuals experienced prolonged work absenteeism and modified activities ≥2 years post-ACL injury. ACL injury was associated with significant direct and indirect costs, and early ACL reconstruction may be less cost-effective than rehabilitation. Only three studies evaluated meniscal injury outcomes (all evaluated HRQoL).

CONCLUSION

There is a very-low certainty of evidence that PCS scores ≥2 years post-ACL injury are worse than uninjured controls and decline over time, whereas MCS scores remain high. ACL injury can result in prolonged work absenteeism and high health/economic costs. Further studies are needed to determine the long-term burden of traumatic meniscal injury.

Osteoarthritis in Athletes Versus Nonathletes: A Systematic Review

INTRODUCTION

Joint overload and sport-related injuries may accelerate the development of osteoarthritis (OA). A systematic review of the literature was performed to establish the risk of athletes to develop premature OA compared with nonathletes.

MATERIALS AND METHODS

This systematic review was conducted according to the PRISMA guidelines. PubMed, Google scholar, Embase, and Web of Science databases were accessed in June 2021. All the published clinical studies investigating OA onset in athletes versus nonathletes were considered. Studies reporting data on secondary and/or post-traumatic OA were excluded.

RESULTS

Data from 32 articles (20,288 patients) were retrieved. The mean age was 67.8±10.0 years and the mean body mass index was 25.0±2.5 kg/m2. 74% (6859 patients) of the athletes suffered from premature OA. Of them, 21% were active in soccer, 11% in handball, 11% in ice-hockey, 3% in football, and 0.3% in rugby. 26% of the athletes reported no significant differences in OA progression compared with healthy controls. Of these athletes, 47% were runners, 5% dancers, and 1% triathletes.

CONCLUSION

Certain sports, such as soccer, handball, ice-hockey, and rugby are more likely to be associated with premature knee and hip OA. Conversely, runners and ballet dancers do not evidence significant increase in OA. Moderate and recreational exposure to aerobic sports does not accelerate the development of OA.

Is musculoskeletal pain related to locomotive syndrome even in young and middle-aged adults?

OBJECTIVES

Locomotive syndrome (LS) is the leading cause of persons needing long-term care in old age and is characterized by locomotive organ impairment including musculoskeletal pain. The aim was to examine the association between musculoskeletal pain and LS in young and middle-aged persons.

METHODS

A total of 836 participants (male 667, female 169; mean age 44.4 years) were examined in this cross-sectional study. The LS was evaluated by three screening tools: the two-step test, the stand-up test, and the 25-question Geriatric Locomotive Function Scale. Musculoskeletal pain, exercise habits, physical function (walkability and muscle strength), and physical activity were also assessed.

RESULTS

The LS was found in 22.8% of participants. The number with musculoskeletal pain was significantly higher in those with the LS. A significant correlation was found between the degree of musculoskeletal pain and exercise habits. Less regular exercise was significantly associated with higher LS prevalence. Physical activity and function were greater in participants with more regular exercise.

CONCLUSION

Musculoskeletal pain was significantly related to LS even in young and middle-aged persons. The present results suggest that control of musculoskeletal pain and improvement of exercise habits in young and middle-aged persons might help prevent the LS.

Electrostimulation has a positive effect on the knee function after knee arthroscopic surgery: A randomized trial

BACKGROUND

There is a wide range of rehabilitation protocols after knee arthroscopic procedures, mainly based on specialist exercises. They comprise of specific stages and key moments but should also be individualized and adjusted to the patient's needs.

OBJECTIVE

The aim of the study was to evaluate the BodyFlow device impact on physical and psychological functioning of the subjects after knee arthroscopy.

METHODS

Ninety three patients were randomly divided into the study and control group. Each study group subject performed mild electrostimulation using the BodyFlow device for three weeks, five times a day for 20 minutes along with the standard rehabilitation protocol. Control group subjects were treated according to the standard rehabilitation protocol after knee arthroscopy. Healthy and operated lower limb size, a range of the knee joint motion, and the flexor and extensor strength were measured 3, 6, and 9 weeks after arthroscopy. At each measurement, the SF-36 and KOOS surveys were collected.

RESULTS

On study day 21, a positive, statistically significant, difference in the knee joint size, range of flection and extension, flexor and extensor strength as well as all KOOS survey subscales and physical functioning categories included in the SF-36 survey was observed. On study day 63, positive effects persisted and significant differences in other categories included in the SF-36 survey were observed.

CONCLUSION

Application of mild electrostimulation using the BodyFlow device has a positive impact on the swelling in the knee joint region, range of motion, extensor and flexor strength as well as physical, psychological, and social functioning.

Ground Reaction Forces Are Predicted with Functional and Clinical Tests in Healthy Collegiate Students

Increased vertical and posterior ground reaction forces (GRFs) are associated with anterior cruciate ligament (ACL) injury. If a practical means to predict these forces existed, ACL injury risk could be attenuated. Forty-two active college-age individuals (21 females, 20.66 ± 1.46 y, 70.70 ± 2.36 cm, 82.20 ± 7.60 kg; 21 males, 21.57 ± 1.28 y, 65.52 ± 1.87 cm, 64.19 ± 9.05 kg) participated in this controlled laboratory study. GRFs were ascertained by having the subjects perform a unilateral landing task onto a force plate. Several clinical measures (Fat Free Mass (FFM), dorsiflexion passive range of motion (DPROM), isometric peak force of the lateral hip rotators, knee flexor/extensor peak force ratio (H:Q), the completion of the overhead deep squat), two functional tests (Margaria–Kalamen, Single Leg Triple Hop (SLTH)), and sex served as the predictor variables. Regression models to predict the GRFs normalized to the FFM (nGRFz, nGRFy) were generated. nGRFz was best predicted with a linear regression equation that included SLTH and DPROM (adjusted R² = 0.274; p = 0.001). nGRFy was best predicted with a linear regression equation that included H:Q, FFM, and DPROM (adjusted R² = 0.476; p < 0.001). Simple clinical measures and functional tests explain a small to moderate amount of the variance associated with the FFM normalized vertical and posterior GRFs in active college-age individuals.

Post-traumatic osteoarthritis diagnosed within 5 years following ACL reconstruction

PURPOSE

The purpose was to calculate the incidence of osteoarthritis in individuals following Anterior Cruciate Ligament Reconstruction (ACLR) in a large, national database and to examine the risk factors associated with OA development.

METHODS

A commercially available insurance database was queried to identify new diagnoses of knee OA in patients with ACLR. The cumulative incidence of knee OA diagnoses in patients after ACLR was calculated and stratified by time from reconstruction. Odds ratios were calculated using logistic regression to describe factors associated with a new OA diagnosis including age, sex, BMI, meniscus involvement, osteochondral graft use, and tobacco use.

RESULTS

A total of 10,565 patients with ACLR were identified that did not have an existing diagnosis of OA, 517 of which had a documented new diagnosis of knee OA 5 years after ACL reconstruction. When stratified by follow-up time points, the incidence of a new OA diagnosis within 6 months was 2.3%; within a 1-year follow-up was 4.1%; within 2 years, follow-up was 6.2%, within 3 years, follow-up was 8.4%; within 4 years, follow-up was 10.4%; and within 5 years, follow-up was 12.3%. Risk factors for new OA diagnoses were age (OR 2.44, P < 0.001), sex (OR 1.2, P = 0.002), obesity (OR 1.4, P < 0.001), tobacco use (OR = 1.3, P = 0.001), and meniscal involvement (OR 1.2, P = 0.005).

CONCLUSION

Approximately 12% of patients presenting within 5 years following ACLR are diagnosed with OA. Demographic factors associated with an increased risk of a diagnosis of PTOA within 5 years after ACLR are age, sex, BMI, tobacco use, and concomitant meniscal surgery. Clinicians should be cognizant of these risk factors to develop risk profiles in patients with the common goal to achieve optimal long-term outcomes after ACLR.

LEVEL OF EVIDENCE

III.

Osteoarthritis and ACL Reconstruction-Myths and Risks

PURPOSE OF REVIEW

Anterior cruciate ligament (ACL) injury is one of the most common ligamentous injuries suffered by athletes participating in cutting sports. A common misperception is that ACL reconstruction can prevent osteoarthritis (OA). The goal of this paper is to review and discuss the contributing factors for the development of OA following ACL injury.

RECENT FINDINGS

There has been interesting new research related to ACL reconstruction. As understanding of knee biomechanics following ACL injury and reconstruction has changed over time, many surgeons have changed their surgical techniques to low anterior drilling to position their femoral tunnel in an attempt to place the ACL in a more anatomic position. Even with this change in the femoral tunnel position, 85% of knees following ACL reconstruction have abnormal tibial motion compared to contralateral non-injured knees. Studies have shown increases in inflammatory cytokines in the knee following ACL injury, and newer MRI sequences have allowed for earlier objective detection of degenerative changes to cartilage following injury. Recent studies have shown that injecting IL-1 receptor antagonist and corticosteroids can modulate the post-injury inflammatory cascade. ACL reconstruction does not prevent the development of OA but can improve knee kinematics and reduce secondary injury to the cartilage and meniscus. Advancements in imaging studies has allowed for earlier detection of degenerative changes in the knee, which has allowed researchers to study how new interventions can alter the course of degenerative change in the knee following ACL injury.

Running Dose and Risk of Developing Lower-Extremity Osteoarthritis

Whether or not running leads to the development of knee and hip osteoarthritis has been a much-debated topic and is often a question patients pose to their physicians. Recent literature adds to a growing body of evidence suggesting that lower-dose running may be protective against the development of osteoarthritis, whereas higher-dose running may increase one's risk of developing lower-extremity osteoarthritis. However, running dose remains challenging to define, leading to difficulty in providing firm recommendations to patients regarding the degree of running which may be safe. Furthermore, when counseling patients regarding their risk of developing lower-extremity osteoarthritis secondary to running, clinicians must consider many additional factors, such as the numerous health benefits from running and individual risk factors for developing osteoarthritis.

Prevalence of Radiographic Knee Osteoarthritis After Anterior Cruciate Ligament Reconstruction, With or Without Meniscectomy: An Evidence-Based Practice Article

Reference:  Claes S, Hermie L, Verdonk R, Bellemans J, Verdonk P. Is osteoarthritis an inevitable consequence of anterior cruciate ligament reconstruction? A meta-analysis. Knee Surg Sports Traumatol Arthrosc. 2013;21(9):1967-1976.

CLINICAL QUESTION

  What is the prevalence of radiographic knee osteoarthritis (OA) at a mean follow-up equal to or greater than 10 years after autologous anterior cruciate ligament (ACL) reconstruction, with or without meniscectomy?

DATA SOURCES

  The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) reporting guidelines were used to conduct this meta-analysis. Studies were identified by searching PubMed, MEDLINE, EMBASE, and Cochrane Library dating from their earliest file until October 2010. Key terms applied for searching were anterior cruciate ligament or ACL, autologous, follow-up, long-term, outcome, reconstruction, results, treatment, and (osteo)arthritis or osteoarthrosis. The reference lists of included studies were also manually checked to ensure that relevant articles were not omitted.

STUDY SELECTION

  The authors limited their search to English- and French-language journals. Included studies provided radiographic outcomes after autologous ACL reconstruction and had a mean follow-up of ≥10 years. Excluded studies evaluated ACL reconstruction with major concomitant surgical procedures (eg, meniscal allograft transplantation, high tibial osteotomy). In addition, data from 2 studies completed by the same research team with identical patient populations were limited to the article with the longest follow-up. Finally, manuscripts with inaccurate or incomplete data were excluded.

DATA EXTRACTION

  The following key characteristics of each study were extracted: type of study (prospective or retrospective); ACL surgical procedure (eg, open or arthroscopic bone-patellar tendon-bone graft); time frame of surgery; mean follow-up (in years) post-ACL reconstruction; total number of participants with radiographs; total number of participants with radiographic OA at follow-up; and number of participants with meniscectomy before, during, or after ACL reconstruction. Although the OA diagnosis was based on radiographic criteria, the included studies used 4 OA classifications and grading scales: Ahlbäck, Fairbanks, Kellgren and Lawrence, and International Knee Documentation Committee. Regardless of classification or grading scale, OA was defined as the presence of joint-space narrowing: Ahlbäck grades 1 through 5, modified Fairbanks grades 2 and 3, Kellgren and Lawrence ≥2, and International Knee Documentation Committee grades C and D. Tibiofemoral and patellofemoral OA data were collapsed due to the lack of reporting specificity among the studies. Participants were categorized into a meniscectomy or nonmeniscectomy group if this information was reported. Partial or total meniscectomies before, during, or after ACL reconstruction were collapsed regardless of location (medial or lateral compartment), and those patients who underwent a meniscal repair were grouped into the nonmeniscectomy group. Data were analyzed using odds ratios, the Cochran χ2 test, and a random-effects meta-regression analysis. The DerSimonian and Laird approach was used to assess study heterogeneity. P values below .05 were considered statistically significant.

MAIN RESULTS

  The initial computerized database search resulted in 211 possible studies. However, after the authors applied the inclusionary and exclusionary criteria, only 16 studies were relevant. A total of 1554 participants were available at the follow-up period. Mean follow-up ranged from 10 to 24.5 years; 11 of the 16 articles had a mean follow-up between 10 and 12 years. Heterogeneity was large (I2 = 96%), which indicated that the included studies generated a wide range of knee OA prevalence (2%-79%). Almost 28% (95% confidence interval [CI] = 16.3%, 43.5%) of participants had radiographic knee OA. A total of 1264 participants were involved in studies that evaluated meniscectomies (n = 11). Among the 614 participants with either partial or total meniscectomies, 50.4% had radiographic knee OA (95% CI = 27.4%, 73.1%). In contrast, only 16.4% (95% CI = 7.0%, 33.9%) of those without a meniscectomy had radiographic knee OA.

CONCLUSIONS

  The findings of Claes et al reflected a radiographic knee OA prevalence at a minimum average of 10 years' postautologous ACL reconstruction that was lower than commonly perceived (up to 79%). In addition, meniscectomy was an important risk factor (3.54-fold increase) for developing OA after ACL reconstruction.

No difference in osteoarthritis after surgical and non-surgical treatment of ACL-injured knees after 10 years

PURPOSE

Aim of this study was to record and compare the functional and activity level as well as the manifestations of osteoarthritis after isolated ACL ruptures between patients with conservative treatment and ACL reconstruction with hamstrings tendon graft.

METHODS

Thirty-two patients diagnosed with ACL rupture were recorded. Clinical examination included the Tegner and Lysholm activity scale, the International Knee Documentation Committee Subjective Form and KT-1000 arthrometer. Narrowing of the medial and lateral joint spaces was assessed using the IKDC knee examination score.

RESULTS

Median follow-up was 10.3 years (range 10-11). Fifteen patients were conservatively treated (median age 33 years, range 25-39). Seventeen patients were operated (median age 31 years, range 20-36). There was significant difference between the mean values of IKDC scores in favour of the ACL-reconstruction group of patients, 86.8 (SD 6.5) versus 77.5 (SD 13.8), respectively (p = 0.04). The mean value of anteroposterior tibial translation was 1.5 mm (SD 0.2) for ACL-reconstruction group of patients, while the corresponding mean value for ACL-conservative group was 4.5 mm (SD 0.5), p = 0.03. Four patients in ACL-reconstruction group had radiological findings of grade C or D according to IKDC form. In ACL-conservative group, five patients presented similar signs (n.s.).

CONCLUSIONS

ACL reconstruction using hamstrings autograft resulted in better functional outcome and laxity measurements than ACL-conservative management. However, the incidence of radiological osteoarthritis was similar between the two groups and independent on the pre-operative grade of laxity and functional status of the patients. Equally, bone bruises were not found as a risk factor for the development of osteoarthritis after ACL rupture.

LEVEL OF EVIDENCE

Prospective randomized study, Level II.

The Relationship between Anterior Cruciate Ligament Injury and Osteoarthritis of the Knee

Anterior cruciate ligament (ACL) tears are a common injury, particularly in the athletic and youth populations. The known association between ACL injury and subsequent osteoarthritis (OA) of the knee merits a more in-depth understanding of the relationship between the ACL-injured knee and osteoarthritis. ACL injury, especially with concomitant meniscal or other ligamentous pathology, predisposes the knee to an increased risk of osteoarthritis. ACL insufficiency results in deterioration of the normal physiologic knee bending culminating in increased anterior tibial translation and increased internal tibial rotation. This leads to increased mean contact stresses in the posterior medial and lateral compartments under anterior and rotational loading. However, surgical reconstruction of the ACL has not been shown to reduce the risk of future OA development back to baseline and has variability based on operative factors of graft choice, timing of surgery, presence of meniscal and chondral abnormalities, and surgical technique. Known strategies to prevent OA development are applicable to patients with ACL deficiency or after ACL reconstruction and include weight management, avoidance of excessive musculoskeletal loading, and strength training. Reconstruction of the ACL does not necessarily prevent osteoarthritis in many of these patients and may depend on several external variables.