Anterior cruciate ligament tears and associated injuries

Heterotopic ossification postsuperficial medial collateral ligament pie-crusting: a case report

Anterior cruciate ligament and meniscus tears are common among sports injuries. There are different techniques for addressing anterior cruciate ligament and meniscus tears, with distinct indications, advantages, and disadvantages. We present the case of a 23-year-old male who underwent right anterior cruciate ligament reconstruction and posterior horn medial meniscus repair using an all-inside technique via superficial medial collateral ligament (sMCL) pie-crusting. Clinical examination and radiological investigations a few months later identified calcifications on the medial side of the right knee. We diagnosed the patient with heterotopic ossification post-sMCL pie-crusting; no apparent causal factors were present. To our knowledge, there have been no documented instances of heterotopic ossification following sMCL pie-crusting. In conclusion, heterotopic ossification may occur after sMCL pie-crusting; further studies are needed on this subject.

Pediatric ACL Reconstruction in Children-An Evaluation of the Transphyseal Technique's Efficacy and Safety

INTRODUCTION

Injuries of the anterior cruciate ligament (ACL) are commonly found in the general population, both among adult and pediatric patients, and their incidence has been increasing in recent years. Most of the late literature agrees that surgical reconstruction of the ACL is effective in improving long-term outcomes in pediatric patients, while others in the past have pleaded for non-surgical management.

PURPOSE/HYPOTHESIS

Our study aims to verify if ACL reconstruction (ACLR) using transphyseal technique in skeletally immature patients will provide angular deviations or growth restrictions.

STUDY DESIGN

Retrospective cohort study; Level of evidence 4.

METHODS

We perfomed a retrospective study to verify if transphyseal ACLR in children with less than or equal to 2 years of remaining growth leads to either limb length discrepancies or axis deviations.

RESULTS

Most patients who were treated using transphyseal technique showed significant improvements in their functional scores. There were statistically significant differences in lateral distal femoral angles (LDFA) and medial proximal tibial angles (MPTA), with no clinical impact. There was no significant limb length discrepancy (LLD) during the 2-year follow-up.

CONCLUSIONS

Transphyseal ACLR is safe among children who have less than or equal to 2 years of remaining growth and brings no risk of axis deviations or limb length discrepancy.

Combined anterior cruciate and lateral collateral ligaments reconstruction with ipsilateral hamstring autograft: surgical technique

Different surgical techniques have been proposed to reconstruct combined anterior cruciate (ACL) and lateral collateral ligaments (LCL). Although these surgical techniques are reliable and reproducible, the number of autologous grafts needed for the reconstruction could be a limiting factor, especially when patients present with multi-ligament knee injuries and the posterior cruciate ligament is also torn. In addition, some of these techniques are not easy to master and have a steep learning curve. We present a surgical procedure that has been used over the last 18 years to reconstruct combined ACL and LCL injuries and has become a reproducible, feasible and time-efficient procedure to approach combined ACL and LCL injuries using an ipsilateral hamstring autograft.

No evidence for the most appropriate postoperative rehabilitation protocol following anterior cruciate ligament reconstruction with concomitant articular cartilage lesions: a systematic review

PURPOSE

Anterior cruciate ligament (ACL) rupture commonly occurs in conjunction with articular cartilage injury. However, there is no consensus on the most appropriate rehabilitation which should be carried out for ACL reconstruction (ACLR) and the surgical management of articular cartilage lesions of the knee. The purpose of this study was to systematically review the literature to investigate the recommended rehabilitation protocol for patients undergoing ACLR with concomitant articular cartilage injury with a view to develop guidelines on the most appropriate treatment.

METHODS

Two reviewers independently searched five database for randomised controlled trials (RCTs), non-randomised comparative and retrospective cohort studies (CS) describing the management of concomitant ACL rupture and articular cartilage injury and the postoperative rehabilitation regimen. Risk of bias was performed using a modified Downs & Black's checklist. The primary outcome was specific rehabilitation protocols including weight-bearing status, immobilisation, continuous passive motion (CPM), and return to play criteria. Secondary outcomes included patient-reported outcomes. A best evidence synthesis was performed.

RESULTS

The review yielded six studies which reported on rehabilitation techniques. All studies were of low methodological quality. There was considerable variability in not only the chondral lesion reported but also the treatment techniques utilised and especially the rehabilitation regimes. No consensus was found on weight-bearing status, postoperative immobilisation, the use of CPM, or return to play criteria. Given the quality of the papers, there was no evidence to recommend any specific rehabilitation regime in the postoperative management of concomitant ACLR and articular cartilage lesions.

CONCLUSION

This systematic review revealed that despite how common concomitant ACL rupture and articular cartilage injury is, there is no evidence to support one, most appropriate rehabilitation protocol. From a clinical perspective, decisions on postoperative rehabilitation for patients undergoing ACLR and treatment of articular cartilage lesions should be made on a case-by-case basis with criteria-based progression until more robust evidence becomes available. A list of specific rehabilitation protocols based on the cartilage restoration technique is provided.

LEVEL OF EVIDENCE

IV.

Intrasubstance Anterior Cruciate Ligament Injuries in the Pediatric Population

Pediatric intrasubstance anterior cruciate ligament (ACL) tears have a significant epidemiologic impact as their numbers continue to grow globally. This review focuses on true pediatric intrasubstance ACL tears, which occur >400,000 times annually. Modifiable and non-modifiable risk factors include intercondylar notch width, ACL size, gender, landing mechanisms, and hormonal variations. The proposed mechanisms of injury include anterior tibial shear and dynamic valgus collapse. ACL tears can be associated with soft tissue and chondral defects. History and physical examination are the most important parts of evaluation, including the Lachman test, which is considered the most accurate physical examination maneuver. Imaging studies should begin with AP and lateral radiographs, but magnetic resonance imaging is very useful in confirming the diagnosis and preoperative planning. ACL injury prevention programs targeting high risk populations have been proven to reduce the risk of injury, but lack uniformity across programs. Pediatric ACL injuries were conventionally treated nonoperatively, but recent data suggest that early operative intervention produces best long term outcomes pertaining to knee stability, meniscal tear risk, and return to previous level of play. Current techniques in ACL reconstruction, including more vertically oriented tunnels and physeal sparing techniques, have been described to reduce the risk of physeal arrest and limb angulation or deformity. Data consistently show that autograft is superior to allograft regarding failure rate. Mean durations of postoperative therapy and return to sport were 7 ± 3 and 10 ± 3 months, respectively. These patients have good functional outcomes compared to the general population yet are at increased risk of additional ACL injury. Attempts at primary ACL repair using biological scaffolds are under investigation.

Association of the type of trauma, occurrence of bone bruise, fracture and joint effusion with the injury to the menisci and ligaments in MRI of knee trauma

BACKGROUND

magnetic resonance imaging (MRI) as a noninvasive diagnostic tool may help clinicians in the evaluation of injuries to menisci and ligaments.

PURPOSE

this study assessed the associations between type of trauma to knee joint, bone bruise, fracture and pathological joint effusion with injuries to menisci and ligaments of knee joint.

METHODS

we reviewed knee joint MRI of 175 patients aged less than 45 years old who were referred to MRI center of our University.

RESULTS

statistical analysis showed that tearing of medial meniscus (MM) is significantly more common in sport related trauma (p= 0.045) but tearing of medial collateral ligament (MCL) is significantly more common in non-sport related trauma (p= 0.005). Existence of bone bruise in knee MRI is negatively associated with tearing of medial meniscus (MM) (p=0.004) and positively associated with tearing of anterior cruciate ligament (ACL) (p=0.00047) and medial collateral ligament (MCL) (p = 0.0001). Existence of fracture is associated with decreased risk of the tearing of ACL and MM (p=0.04, p=0.001 respectively). Pathologic joint effusion is significantly more common in ACL and MCL tearing (p=0.0001, p=0.004 respectively).

CONCLUSIONS

as diagnostic clues, bone bruise, fracture and joint effusion may help radiologists for better assessment of injury to menisci and ligaments in MRI of patients with knee trauma.

Pathogenesis of post-traumatic OA with a view to intervention

Post-traumatic osteoarthritis (PTOA) subsequent to joint injury accounts for over 12% of the overall disease burden of OA, and higher in the most at-risk ankle and knee joints. Evidence suggests that the pathogenesis of PTOA may be related to inflammatory processes and alterations to the articular cartilage, menisci, muscle and subchondral bone that are initiated in the acute post-injury phase. Imaging of these early changes, as well as a number of biochemical markers, demonstrates the potential for use as predictors of future disease, and may help stratify patients on the likelihood of their developing clinical disease. This will be important in guiding future interventions, which will likely target elements of the inflammatory response within the joint, molecular abnormalities related to cartilage matrix degradation, chondrocyte function and subchondral bone remodelling. Until significant improvements are made, however, in identifying patients most at risk for developing PTOA--and therefore those who are candidates for therapy--primary prevention programmes will remain the most effective current management tools.

Spectrum of injuries associated with paediatric ACL tears: an MRI pictorial review

OBJECTIVE

Magnetic resonance imaging (MRI) findings in anterior cruciate ligament (ACL) injury are well known, but most published reviews show obvious examples of associated injuries and give little focus to paediatric patients. Here, we demonstrate the spectrum of MRI appearances at common sites of associated injury in adolescents with ACL tears, emphasising age-specific issues.

METHODS

Pictorial review using images from children with surgically confirmed ACL tears after athletic injury.

RESULTS

ACL injury usually occurs with axial rotation in the valgus near full extension. The MRI findings can be obvious and important to management (ACL rupture), subtle but clinically important (lateral meniscus posterior attachment avulsion), obvious and unimportant to management (femoral condyle impaction injury), or subtle and possibly important (medial meniscocapsular junction tear). Paediatric-specific issues of note include tibial spine avulsion, normal difficulty visualising a thin ACL and posterolateral corner structures, and differentiation between incompletely closed physis and impaction fracture.

CONCLUSION

ACL tear is only the most obvious sign of a complex injury involving multiple structures. Awareness of the spectrum of secondary findings illustrated here and the features distinguishing them from normal variation can aid in accurate assessment of ACL tears and related injuries, enabling effective treatment planning and assessment of prognosis.

TEACHING POINTS

• The ACL in children normally appears thin or attenuated, while thickening and oedema suggest tear. • Displaced medial meniscal tears are significantly more common later post-injury than immediately. • The meniscofemoral ligaments merge with the posterior lateral meniscus, complicating tear assessment. • Tibial plateau impaction fractures can be difficult to distinguish from a partially closed physis. • Axial MR sequences are more sensitive/specific than coronal for diagnosis of medial collateral ligament (MCL) injury.

Augmentation of bone tunnel healing in anterior cruciate ligament grafts: application of calcium phosphates and other materials

Bone tunnel healing is an important consideration after anterior cruciate ligament (ACL) replacement surgery. Recently, a variety of materials have been proposed for improving this healing process, including autologous bone tissue, cells, artificial proteins, and calcium salts. Amongst these materials are calcium phosphates (CaPs), which are known for their biocompatibility and are widely commercially available. As with the majority of the materials investigated, CaPs have been shown to advance the healing of bone tunnel tissue in animal studies. Mechanical testing shows fixation strengths to be improved, particularly by the application of CaP-based cement in the bone tunnel. Significantly, CaP-based cements have been shown to produce improvements comparable to those induced by potentially more complex treatments such as biologics (including fibronectin and chitin) and cultured cells. Further investigation of CaP-based treatment in the bone tunnels during ACL replacement is therefore warranted in order to establish what improvements in healing and resulting clinical benefits may be achieved through its application.

Cartilage in anterior cruciate ligament-reconstructed knees: MR imaging T1{rho} and T2--initial experience with 1-year follow-up

PURPOSE

To longitudinally evaluate cartilage matrix changes by using magnetic resonance (MR) imaging T1(ρ) (T1 relaxation time in rotating frame) and T2 quantification and to study the relationship between meniscal damage and cartilage degeneration in anterior cruciate ligament (ACL)-reconstructed knees.

MATERIALS AND METHODS

This was an institutional review board-approved, HIPAA-compliant study. Informed consent was obtained. Twelve patients with acute ACL injuries were imaged with 3.0-T MR imaging at baseline (after injury and prior to ACL reconstruction) and 1 year after ACL reconstruction. Ten age-matched healthy subjects were studied as controls. Cartilage T1(ρ) and T2 were quantified in full thickness, superficial, and deep layers of defined subcompartments at baseline and follow-up in ACL-injured knees and were compared with measures acquired in matched regions of control knees. Meniscal lesions were graded by using modified subscores of the Whole-Organ Magnetic Resonance Imaging Score system.

RESULTS

T1(ρ) values of the posterolateral tibial cartilage in ACL-injured knees were significantly elevated at baseline compared with T1(ρ)values of control knees and were not fully recovered at 1-year follow-up. T1(ρ) values of weight-bearing medial femorotibial cartilage in ACL-injured knees were significantly elevated at 1-year follow-up compared with those of control knees. No significant differences in T2 values between ACL-injured and control knees were found. Patients with lesions in the posterior horn of the medial meniscus showed a greater increase of T1(ρ) and T2 from baseline to follow-up in adjacent cartilage than patients without lesions in the medial meniscus.

CONCLUSION

Quantitative MR imaging T1(ρ) and T2 enable detection of changes in the cartilage matrix of ACL-reconstructed knees as early as 1 year after ACL reconstruction.

MRI-detected subchondral bone marrow signal alterations of the knee joint: terminology, imaging appearance, relevance and radiological differential diagnosis

OBJECTIVE

To discuss terminology, radiological differential diagnoses and significance of magnetic resonance imaging (MRI)-detected subchondral bone marrow lesions (BMLs) of the knee joint.

METHODS

An overview of the published literature is presented. In addition, the radiological appearance and differential diagnosis of subchondral signal alterations of the knee joint are discussed based on expert consensus. A recommendation for terminology is provided and the relevance of these imaging findings for osteoarthritis (OA) research is emphasized.

RESULTS

A multitude of differential diagnoses of subchondral BMLs may present with a similar aspect and signal characteristics. For this reason it is crucial to clearly and specifically define the type of BML that is being assessed and to use terminology that is appropriate to the condition and the pathology. In light of the currently used terminology, supported by histology, it seems appropriate to apply the widely used term "bone marrow lesion" to the different entities of subchondral signal alterations and in addition to specifically and precisely define the analyzed type of BML. Water sensitive sequences such as fat suppressed T2-weighted, proton density-weighted, intermediate-weighted fast spin echo or short tau inversion recovery (STIR) sequences should be applied to assess non-cystic BMLs as only these sequences depict the lesions to their maximum extent. Assessment of subchondral non-cystic ill-defined BMLs on gradient echo-type sequences should be avoided as they will underestimate the size of the lesion. Differential diagnoses of OA related BMLs include traumatic bone contusions and fractures with or without disruption of the articular surface. Osteonecrosis and bone infarcts, inflammation, tumor, transient idiopathic bone marrow edema, red marrow and post-surgical alterations should also be considered.

CONCLUSION

Different entities of subchondral BMLs that are of relevance in the context of OA research may be distinguished by specific imaging findings, patient characteristics, symptoms, and history and are discussed in this review.

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.

The acutely ACL injured knee assessed by MRI: are large volume traumatic bone marrow lesions a sign of severe compression injury?

OBJECTIVES

To map by magnetic resonance imaging (MRI) and quantitative MRI (qMRI) concomitant fractures and meniscal injuries, and location and volume of traumatic bone marrow lesions (BMLs) in the acutely anterior cruciate ligament (ACL) injured knee. To relate BML location and volume to cortical depression fractures, meniscal injuries and patient characteristics.

METHODS

One hundred and twenty-one subjects (26% women, mean age 26 years) with an ACL rupture to a previously un-injured knee were studied using a 1.5T MR imager within 3 weeks from trauma. Meniscal injuries and fractures were classified by type, size and location. BML location and volume were quantified using a multi-spectral image data set analyzed by computer software, edited by an expert radiologist.

RESULTS

Fractures were found in 73 (60%) knees. In 67 (92%) of these knees at least one cortical depression fracture was found. Uni-compartmental meniscal tears were found in 44 (36%) subjects and bi-compartmental in 24 (20%). One hundred and nineteen (98%) knees had at least one BML, all but four (97%) located in the lateral compartment. Knees with a cortical depression fracture had larger BML volumes (P<0.001) than knees without a cortical depression fracture, but no associations were found between meniscal tears and BML volume or fractures. Older age at injury was associated with smaller BML volumes (P<0.01).

CONCLUSION

A majority of the ACL injured knees had a cortical depression fracture, which was associated with larger BML volumes. This indicates strong compressive forces to the articular surface and cartilage at the time of injury, which may constitute an additional risk factor for later knee osteoarthritis development.