Operative treatment of primary anterior cruciate ligament rupture in adults

Repair potential of self-assembling peptide hydrogel in a mouse model of anterior cruciate ligament reconstruction

Purpose

Establishing zonal tendon-to-bone attachment could accelerate the anterior cruciate ligament reconstruction (ACLR) rehabilitation schedule and facilitate an earlier return to sports. KI24RGDS is a self-assembling peptide hydrogel scaffold (SAPS) with the RGDS amino acid sequence. This study aimed to elucidate the therapeutic potential of KI24RGDS in facilitating zonal tendon-to-bone attachment after ACLR.

Methods

Sixty-four C57BL/6 mice were divided into the ACLR + SAPS and ACLR groups. ACLR was performed using the tail tendon. To assess the maturation of tendon-to-bone attachment, we quantified the area of mineralized fibrocartilage (MFC) in the tendon graft with demeclocycline. Immunofluorescence staining of α-smooth muscle actin (α-SMA) was performed to evaluate progenitor cell proliferation. The strength of tendon-to-bone attachment was evaluated using a pull-out test.

Results

The MFC and maximum failure load in the ACLR + SAPS group were remarkably higher than in the ACLR group on Day 14. However, no significant difference was observed between the two groups on Day 28. The number of α-SMA-positive cells in the tendon graft was highest on Day 7 after ACLR in both the groups and was significantly higher in the ACLR + SAPS group than in the ACLR group.

Conclusion

This study highlighted the latent healing potential of KI24RGDS in facilitating early-stage zonal attachment of tendon grafts and bone tunnels post-ACLR. These findings may expedite rehabilitation protocols and shorten the timeline for returning to sports.

Level of Evidence

Not applicable.

Eighteen-year outcome of anterior cruciate ligament reconstruction with patellar tendon or hamstring autograft

PURPOSE

To evaluate patient reported outcomes and radiographic arthritic changes of transtibial anterior cruciate ligament reconstruction (ACLR) with either bone-patellar tendon-bone (BPTB) or hamstrings (HS) auto-grafts at a minimum of 15-year follow-up.

METHODS

Ninety-four patients (51 of the HS group, 43 of BPTB group) who were operated between the years 2000 to 2005 in two tertiary referral hospitals were contacted and invited to a retrospective evaluation. The interview included subjective outcomes using the Lysholm knee scoring questionnaire, Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), Tegner activity level scale, Visual Analogue Scale (VAS) for pain and patients' satisfaction scale. Knee examination included measurements of motion and stability. Knee radiographs were evaluated for osteoarthritic changes according to the Kellgren-Lawrence (KL) score.

RESULTS

The average evaluation time from surgery was 18.6 years. Subjectively, there was no significant difference between groups except for a better post-operative level of activity and satisfaction in the HS group. Objectively, there was no significant difference between groups in knee stability and range of motion. Most patients had grade KL ≤ 1 radiographic osteoarthritits changes and there was no significant difference between groups. Recurrent complete tear of the reconstructed graft occurred in 3 patients of each group. In both groups 84% had no further surgery while the indications for further surgery were mostly a meniscal tear or tibial hardware removal.

CONCLUSIONS

Very long-term outcomes and clinical stability of transtibial HS or BPTB graft ACL reconstruction are good with low rate of graft failure and radiographic osteoarthritis.

The effects of immobilization duration on joint contracture formation after anterior cruciate ligament reconstruction in rats

BACKGROUND

Both myogenic and arthrogenic factors contribute to contracture formation after anterior cruciate ligament reconstruction surgery. However, effects of immobilization duration on myogenic and arthrogenic contractures after surgery are unknown. We examined the effects of immobilization duration on contracture formation.

METHODS

Rats were divided into groups according to treatment received: untreated control, knee immobilization, anterior cruciate ligament reconstruction, and anterior cruciate ligament reconstruction plus immobilization. Extension range of motion before and after myotomy as well as histomorphological knee changes were assessed two or four weeks after experiment commencement. Range of motion before myotomy mainly represents contractures due to myogenic factors. Range of motion after myotomy represents arthrogenic factors.

FINDINGS

Range of motion before and after myotomy was decreased in the immobilization, reconstruction, and reconstruction plus immobilization groups at both timepoints. In the reconstruction plus immobilization group, range of motion before and after myotomy was significantly smaller than in the immobilization and reconstruction groups. Shortening and thickening of the posterior joint capsule was induced in the immobilization and reconstruction groups. In the reconstruction plus immobilization group, capsule shortening was facilitated via adhesion formation, as compared to the immobilization and reconstruction groups.

INTERPRETATION

Our results indicate that immobilization after anterior cruciate ligament reconstruction surgery facilitates contracture formation via exacerbation of both myogenic and arthrogenic contractures within two weeks. Capsule shortening would be one of the main mechanisms for severe arthrogenic contracture observed in the reconstruction plus immobilization group. Periods of joint immobilization after surgery should be minimized to reduce contracture.

Hamstring, bone-patellar tendon-bone, quadriceps and peroneus longus tendon autografts for primary isolated posterior cruciate ligament reconstruction: a systematic review

INTRODUCTION

Several autografts are available to reconstruct the posterior cruciate ligament (PCL).

SOURCE OF DATA

Current scientific literature published in PubMed, Google scholar, Embase and Scopus.

AREAS OF AGREEMENT

Hamstring, bone-patellar tendon-bone (BPTB), quadriceps and peroneus longus (PLT) are the most common tendon autografts used for primary isolated PCL reconstruction.

AREAS OF CONTROVERSY

The optimal tendon source for PCL reconstruction remains nevertheless debated. Identifying the most suitable tendon autograft could assist the surgeon during primary PCL reconstruction.

GROWING POINTS

The present study compared the outcome of PCL reconstruction using hamstring, BPTB, quadriceps and PLT autografts. The focus was on patient-reported outcome measures (PROMs), joint laxity, range of motion and complications.

AREAS TIMELY FOR DEVELOPING RESEARCH

All autografts are viable options for PCL reconstruction, with BTB and hamstring autografts demonstrating superior PROMs. However, further clinical investigations are required to determine the ideal autograft construct.

Anterior cruciate ligament reconstruction, can an anatomic femoral tunnel be achieved with the trans-tibial technique? Cadaveric study

Purpose

To evaluate the possibility to access the anatomic femoral insertion of the anterior cruciate ligament (ACL) through trans-tibial (TT) and trans-portal technique, for ACL reconstruction in an independent way. To register anatomical characteristics of the TT tunnels.

Methods

Ten formaldehyde preserved knee anatomic articular specimens were dissected. Femoral tunnels were confectioned reproducing the original topography of the ACL. First, the femoral tunnel was made with the independent trans-portal technique. Then, utilizing the tibial stump of the ACL and tibial guides at 45°, the TT tunnels were confectioned trying to match the previously made femoral tunnel by trans-portal technique.

Results

In all specimens, match between the TT tunnel with the independent trans-portal tunnel was achieved. Mean values for TT coronal angle was 53,0°, for transversal angle 43,3° and for distance from tunnel to joint line 2,55 cm. A horizontalization and medialization of the TT tunnels had to be made to adequately match with the femoral tunnel made by the independent trans-portal technique.

Conclusions

By macroscopic anatomic and independent means, an anatomic femoral tunnel was confectioned with the TT technique matching with the anatomic femoral tunnel made in an independent way. As clinical relevance, the present study allows to anatomically assess the possibility to perform an anatomic femoral tunnel through the TT technique.

Level of evidence

V

Coronal subluxation of the tibiofemoral joint before and after anterior cruciate ligament reconstruction

Background

Studies have shown that medial subluxation of the tibia occurs after anterior cruciate ligament (ACL) rupture. However, it is unclear whether anterior cruciate ligament reconstruction (ACLR) can correct tibial coronal subluxation.

Purpose

To determine whether the tibia is medially subluxated after ACL rupture, and whether ACLR can correct medial subluxation of the tibia.

Study design

Case series; Level of evidence, 4, Retrospective clinical study.

Methods

The distance of tibial coronal subluxation before and after ACLR surgery was measured in 48 patients with ACL rupture and meniscus injury. Tibiofemoral subluxation was defined as the perpendicular distance between the long axis of the tibia and a second parallel line originating at the most proximal aspect of the femoral intercondylar notch. To determine the long axis of the tibia, two circles separated by 5 cm were centered on the proximal tibia. The proximal circle is 5 cm from the tibial plateau, and the distal circle is 5 cm from the proximal circle. The line passing through the center of the two circles was considered the long axis of the proximal tibia. Care was taken to ensure that each patient lied on the back with their patellae facing upward, to minimize rotational variation among the radiographs. At the same time, 30 patients with simple meniscus injury who underwent arthroscopy during the same period were selected to determine the degree of tibiofemoral coronal subluxation as the baseline value. The changes before and after operation were compared, as well as the differences with the baseline data.

Result

The average follow-up period was 21.2 ± 5.8 months. The average distance of tibial coronal subluxation before ACLR was 5.5 ± 2.1 mm, which was significantly different from that of baseline group (7.3 ± 2.1 mm) (P < 0.001). The tibial subluxation after ACLR was 7.7 ± 2.6 mm, which was significantly different from that before operation (P < 0.001). There was no significant difference in the distance between postoperative tibial subluxation and baseline group (P = 0.472).

Conclusion

The tibia was coronally medially subluxated after ACL rupture. ACLR can correct the medial subluxation of tibia. This finding is helpful in the diagnosis of ACL rupture, and can be used to assess the imaging status of the tibiofemoral joint on the coronal plane during or after ACLR.

Maintenance of Ligament Homeostasis of Spheroid-Colonized Embroidered and Functionalized Scaffolds after 3D Stretch

Anterior cruciate ligament (ACL) ruptures are usually treated with autograft implantation to prevent knee instability. Tissue engineered ACL reconstruction is becoming promising to circumvent autograft limitations. The aim was to evaluate the influence of cyclic stretch on lapine (L) ACL fibroblasts on embroidered scaffolds with respect to adhesion, DNA and sulphated glycosaminoglycan (sGAG) contents, gene expression of ligament-associated extracellular matrix genes, such as type I collagen, decorin, tenascin C, tenomodulin, gap junctional connexin 43 and the transcription factor Mohawk. Control scaffolds and those functionalized by gas phase fluorination and cross-linked collagen foam were either pre-cultured with a suspension or with spheroids of LACL cells before being subjected to cyclic stretch (4%, 0.11 Hz, 3 days). Stretch increased significantly the scaffold area colonized with cells but impaired sGAGs and decorin gene expression (functionalized scaffolds seeded with cell suspension). Stretching increased tenascin C, connexin 43 and Mohawk but decreased decorin gene expression (control scaffolds seeded with cell suspension). Pre-cultivation of functionalized scaffolds with spheroids might be the more suitable method for maintaining ligamentogenesis in 3D scaffolds compared to using a cell suspension due to a significantly higher sGAG content in response to stretching and type I collagen gene expression in functionalized scaffolds.

Biceps Femoris Compensates for Semitendinosus After Anterior Cruciate Ligament Reconstruction With a Hamstring Autograft: A Muscle Functional Magnetic Resonance Imaging Study in Male Soccer Players

BACKGROUND

Rates of reinjury, return to play (RTP) at the preinjury level, and hamstring strain injuries in male soccer players after anterior cruciate ligament reconstruction (ACLR) remain unsatisfactory, due to multifactorial causes. Recent insights on intramuscular hamstring coordination revealed the semitendinosus (ST) to be of crucial importance for hamstring functioning, especially during heavy eccentric hamstring loading. Scientific evidence on the consequences of ST tendon harvest for ACLR is scarce and inconsistent. This study intended to investigate the repercussions of ST harvest for ACLR on hamstring muscle function.

HYPOTHESIS

Harvest of the ST tendon for ACLR was expected to have a significant influence on hamstring muscle activation patterns during eccentric exercises, evaluated at RTP in a population of male soccer athletes.

STUDY DESIGN

Controlled laboratory study.

METHODS

A total of 30 male soccer players with a history of ACLR who were cleared for RTP and 30 healthy controls were allocated to this study during the 2018-2019 soccer season. The influence of ACLR on hamstring muscle activation patterns was assessed by comparing the change in T2 relaxation times [ΔT2 (%) = post-exercise-T2pre-exerciseT2pre-exercise] of the hamstring muscle tissue before and after an eccentric hamstring loading task between athletes with and without a recent history of ACLR through use of muscle functional magnetic resonance imaging, induced by an eccentric hamstring loading task between scans.

RESULTS

Significantly higher exercise-related activity was observed in the biceps femoris (BF) of athletes after ACLR compared with uninjured control athletes (13.92% vs 8.48%; P = .003), whereas the ST had significantly lower activity (19.97% vs 25.32%; P = .049). Significant differences were also established in a within-group comparison of the operated versus the contralateral leg in the ACLR group (operated vs nonoperated leg: 14.54% vs 11.63% for BF [P = .000], 17.31% vs 22.37% for ST [P = .000], and 15.64% vs 13.54% for semimembranosus [SM] [P = .014]). Neither the muscle activity of SM and gracilis muscles nor total posterior thigh muscle activity (sum of exercise-related ΔT2 of the BF, ST, and SM muscles) presented any differences in individuals who had undergone ACLR with an ST tendon autograft compared with healthy controls.

CONCLUSION

These findings indicate that ACLR with a ST tendon autograft might notably influence the function of the hamstring muscles and, in particular, their hierarchic dimensions under fatiguing loading circumstances, with increases in relative BF activity contribution and decreases in relative ST activity after ACLR. This between-group difference in hamstring muscle activation pattern suggests that the BF partly compensates for deficient ST function in eccentric loading. These alterations might have implications for athletic performance and injury risk and should probably be considered in rehabilitation and hamstring injury prevention after ACLR with a ST tendon autograft.

Young athletes after ACL reconstruction with asymmetric quadriceps strength at the time of return-to-sport clearance demonstrate drop-landing asymmetries two years later

BACKGROUND

Quadriceps strength asymmetry at the time of return-to-sport (RTS) after anterior cruciate ligament reconstruction (ACLR) contributes to altered landing mechanics. However, the impact of RTS quadriceps strength on longitudinal alterations in landing mechanics, a risk factor for poor knee joint health over time, is not understood. The purpose of this study was to test the hypothesis that young athletes with quadriceps strength asymmetry at the time of RTS clearance after ACLR would demonstrate asymmetric landing mechanics 2 years later compared to those without quadriceps strength asymmetry.

METHODS

We followed 57 young athletes (age at RTS = 17.6 ± 3.0 years; 77% females) with primary, unilateral ACLR for 2 years following RTS clearance. At RTS, we measured isometric quadriceps strength bilaterally and calculated limb-symmetry indices [LSI = (involved/uninvolved)×100%]. Using RTS quadriceps LSI, we divided participants into High-Quadriceps (HQ; LSI ≥ 90%) and Low-Quadriceps (LQ; LSI < 85%) groups. Two years later, we assessed landing mechanics during a drop-vertical jump (DVJ) task using three-dimensional motion analysis. We compared involved/uninvolved limb values and LSI between the HQ and LQ groups using Mann-Whitney U tests.

RESULTS

The LQ group (n = 26) demonstrated greater asymmetry (lower LSI) during landing at 2 years post-RTS for knee flexion excursion (p = 0.016) and peak vertical ground reaction force (p = 0.006) compared to the HQ group (n = 28). There were no group differences in uninvolved or involved limb values for all variables (all p > 0.093).

CONCLUSION

Young athletes after ACLR with quadriceps strength asymmetry at the time of RTS favored the uninvolved limb during DVJ landing 2 years later. These landing asymmetries may relate to long-term knee joint health after ACLR.

Insufficient evidence to support peroneus longus tendon over other autografts for primary anterior cruciate ligament reconstruction: a systematic review

IMPORTANCE

Graft choice for anterior cruciate ligament reconstruction (ACLR) remains a subject of interest among orthopaedic surgeons because no ideal graft has yet been found. Peroneus longus tendon (PLT) has emerged as an alternative autograft for reconstruction in kneeling populations and in simultaneous anterior cruciate ligament (ACL) and medial collateral ligament (MCL) injuries.

OBJECTIVE

To evaluate the current evidence on the outcome of primary ACLR with PLT autograft in adults and donor ankle morbidity, in addition to determining the average PLT graft dimensions from published studies.

EVIDENCE REVIEW

Two independent reviewers searched PubMed, CENTRAL, EMBASE, Scopus and Virtual Health Library databases using the terms "anterior cruciate ligament," "peroneus longus" and "fibularis longus" alone and in combination with Boolean operators AND/OR. Studies evaluating clinical and stability outcomes, graft-donor ankle morbidity and graft dimensions of PLT in ACLR were included. Methodological quality was assessed using the Modified Coleman Methodology Score (mCMS). A narrative analysis is presented using frequency-weighted means wherever feasible. Publication bias was assessed using the ROBIS tool.

FINDINGS

Twelve articles with intermediate-level methodological quality were included. Eight studies assessing the clinical and stability outcomes of reconstruction with PLT showed satisfactory outcomes, similar to those of hamstring tendons (HT). No studies assessed anterior knee pain as an outcome. Six studies evaluated the graft-donor ankle morbidity using general functional foot and ankle scores and non-validated tools, showing favourable outcomes. Nine studies assessed PLT graft diameter, revealing grafts consistently larger than 7 mm among the different preparation techniques, which is comparable with reports of HT grafts.

CONCLUSIONS AND RELEVANCE

The clinical and stability outcomes of ACLR with different PLT autograft preparation techniques are comparable with those of HT during short-term follow-up; however, there is insufficient evidence to support its use in the populations that motivated its implementation. Thus, stronger evidence obtained with the use of validated tools reporting negligible donor-graft ankle morbidity after PLT harvesting is required prior to recommending its routine use, despite the consistency of its dimensions.

LEVEL OF EVIDENCE

Level III.

Saphenous nerve injury after anterior cruciate ligament reconstruction: Reduced numbness area after ligamentoplasty using quadriceps tendon compared with hamstring tendon

PURPOSE

Injury to the infra-patellar branches of the saphenous nerve (IPBSN) is the main neurological complication of anterior cruciate ligament (ACL) reconstruction procedures. Surgical technique using quadriceps tendon (QT) autograft allows a less invasive tibial approach potentially protecting the IPBSN. The aim of this study was to compare the numbness surface of the cutaneous area supplied by the IPBSN after ACL reconstruction using either hamstring tendon (HT) or QT autografts.

METHODS

This was a retrospective comparative cohort study including 51 patients who underwent ACL reconstruction (27 QT and 24 HT) between January 2017 and April 2018. A sensory clinical evaluation was performed on each patient: length of the tibial scar, eventual numbness surface area and the type of sensory disorder were reported. To be considered as an IPBSN lesion, the numbness area had to spread at least one-centimeter away from the scar.

RESULTS

The average follow-up was 15 months. In the HT group, the numbness area surface measured 21.2 ± 19 cm² (0-77) and the scar length was on average 31.3 ± 5.6 mm. In the QT group, the numbness area was reduced to 5 ± 10 cm² (P = .0007) as well as the scar length (13.3 ± 2.8 mm, P < .0001). We counted five (17.8%) and 19 (76%) real IPBSN lesions in the QT and HT groups, respectively (P = .0002). Hypoesthesia was the main sensory disorder observed (87.5%).

CONCLUSION

Numbness area of the cutaneous surface supplied by the IPBSN after ACL reconstruction is reduced using QT autograft compared with HT autograft.

Spontaneous dog osteoarthritis - a One Medicine vision

Osteoarthritis (OA) is a global disease that, despite extensive research, has limited treatment options. Pet dogs share both an environment and lifestyle attributes with their owners, and a growing awareness is developing in the public and among researchers that One Medicine, the mutual co-study of animals and humans, could be beneficial for both humans and dogs. To that end, this Review highlights research opportunities afforded by studying dogs with spontaneous OA, with a view to sharing this active area of veterinary research with new audiences. Similarities and differences between dog and human OA are examined, and the proposition is made that suitably aligned studies of spontaneous OA in dogs and humans, in particular hip and knee OA, could highlight new avenues of discovery. Developing cross-species collaborations will provide a wealth of research material and knowledge that is relevant to human OA and that cannot currently be obtained from rodent models or experimentally induced dog models of OA. Ultimately, this Review aims to raise awareness of spontaneous dog OA and to stimulate discussion regarding its exploration under the One Medicine initiative to improve the health and well-being of both species.

Osteoarthritis occurs spontaneously in pet dogs, which often share environmental and lifestyle risk-factors with their owners. This Review aims to stimulate cooperation between medical and veterinary research under the One Medicine initiative to improve the welfare of dogs and humans.

Dogs have many analogous spontaneous diseases that result in end-stage osteoarthritis (OA).

Inbreeding and the predisposition of certain dog breeds for OA enable easier identification of candidate genetic associations than in outbred humans.

Dog OA subtypes offer a potential stratification rationale for aetiological differences and alignment to analogous human OA phenotypes.

The relatively compressed time course of spontaneous dog OA offers longitudinal research opportunities.

Collaboration with veterinary researchers can provide tissue samples from early-stage OA and opportunities to evaluate new therapeutics in a spontaneous disease model.

Awareness of the limitations and benefits of using clinical veterinary patients in research is important.

"Swiss roll"-like bioactive hybrid scaffolds for promoting bone tissue ingrowth and tendon-bone healing after anterior cruciate ligament reconstruction

The choice of grafts for anterior cruciate ligament (ACL) reconstruction is a critical issue in sports medicine. Previous studies have revealed that scaffolds prepared from a single material could not achieve complete integration between the graft and autogenous bone tunnel. To solve this problem, we hypothesize that combining degradable scaffolds with nondegradable scaffolds can produce a novel hybrid ligament with the advantages of both types of scaffolds. In this study, a bone morphogenetic protein 7 (BMP-7)-loaded polycaprolactone (PCL) nanofibrous membrane was first manufactured as the degradable part of the hybrid ligament by using layer-by-layer (LbL) self-assembly. Then, we fabricated a multifunctional novel hybrid ligament by rolling up this nanofibrous membrane and polyethylene terephthalate (PET) mesh fabric (nondegradable part) into a "swiss roll" structure. The in vitro experimental results showed that this hybrid ligament could significantly improve the biocompatibility of pure PET ligament and further promote cell mineralization. The in vivo experimental results showed that this unique structure significantly promoted the integration of hybrid ligaments and bone tunnels, thereby achieving real "ligamentization" after ACL reconstruction surgery. These results suggest that this novel hybrid biomimetic artificial ligament scaffold provides a new direction for graft selection for ACL reconstruction.

Forward lunge before and after anterior cruciate ligament reconstruction: Faster movement but unchanged knee joint biomechanics

The forward lunge (FL) may be a promising movement to assess functional outcome after ACL reconstruction. Thus, we aimed to investigate the FL movement pattern before and after ACL reconstruction with a comparison to healthy controls to determine if differences were present. Twenty-eight ACL injured participants and 28 matched healthy controls were included. They performed FL movements while sagittal plane biomechanics of the knee and electromyography (EMG) of nine leg muscles was assessed. The ACL injured group was tested before and 10 months after surgery. The perceived knee function and activity level was assessed by questionnaires. The ACL injured group performed the FL significantly slower than the controls before surgery (mean difference: 0.41 s [95%CI: 0.04-0.79 s; p<0.05]) while they performed the FL as fast as the controls after surgery (~28% movement time reduction post-surgery). Perceived knee function and activity level improved significantly post-surgery. The knee joint flexion angle, extensor moment, power, angular velocity in the ACL injured group did not differ from pre to post-surgery. For the ACL injured group, the peak knee extensor moment observed both pre and post-surgery was significantly lower when compared to the controls. The EMG results showed minimal differences. In conclusion, at 10 months post-surgery, the FL was performed significantly faster and the movement time was comparable to that of the controls. While the perceived knee function and activity level improved post-surgery, the knee joint biomechanics were unchanged. This may reflect that knee joint function was not fully restored.

Influence of anthropometric features on peroneus longus graft diameter in Anterior Cruciate Ligament reconstruction: A cohort study

BACKGROUND

Anterior Cruciate Ligament (ACL) is the most common ligament injury during sports activities that was treated with ACL reconstruction. Nowadays, peroneus longus is used in ACL reconstruction. However, it is difficult to predict the peroneus longus graft diameter for ACL reconstruction. Thus, preoperative measurements are very important to predict peroneus longus autograft for ACL reconstruction.

METHODS

A cohort retrospective study was conducted using consecutive sampling method from February 2016 until October 2017 in our center. We recorded patients' characteristics include gender, age, body weight, height, and Body Mass Index (BMI) preoperatively. We measured peroneus longus graft diameter intraoperatively, and analysed data using Spearman correlation.

RESULTS

Thirty-nine patients met inclusion criteria. There were 28 males and 11 females in the peroneus group. From the patients' mean characteristics, age was 25.10 ± 9.16, body weight 71.23 ± 14.17, height 169.13 ± 8.81, and BMI 20.96 ± 3.44. Intraoperative peroneus longus diameter measurement was 8.56 ± 0.82. Spearman correlation showed significant correlation between intraoperative peroneus longus diameter with patient's height, body weight, and BMI with p < 0.05.

CONCLUSION

Patients' characteristics including gender, height, weight, and BMI in preoperative measurements can predict peoneus longus graft diameter intraoperatively.

A LbL-Assembled Bioactive Coating Modified Nanofibrous Membrane for Rapid Tendon-Bone Healing in ACL Reconstruction

Introduction

In anterior cruciate ligament (ACL) reconstruction, hamstring tendon autograft is a well-accepted surgical choice as an alternative ACL graft. But the main disadvantage of autograft is its inefficient healing with host bone-tunnel which will leading to surgery failure.

Methods

A biomimetic nanofibrous membrane for tendon-bone integration is fabricated in this work, which is composed of polycaprolactone (PCL) electrospinning membrane and chitosan/hyaluronic acid (CS/HA) multilayers film.

Results

By using layer-by-layer (LbL) self-assembly this functional CS/HA multilayer films are deposited on the surface of PCL nanofiber to enable the local delivery of stromal cell-derived factor-1 α (SDF-1α) and bone morphogenetic protein-2 (BMP-2) in tendon-bone interface. This membrane can promote cell proliferation and recruitment, as well as inducing the osteogenic differentiation and recruitment of BMSCs.

Conclusion

Further in vivo studies demonstrate that to wrap the tendon autograft using the membrane may afford superior tendon-bone integration and inhibit scar tissue formation in a rabbit ACL reconstruction model. More importantly, the biomechanical properties of the tendon-bone interface have been improved. This study shows that this biomimetic nanofibrous membrane is effective for improving tendon-bone healing after ACL reconstruction surgery.

Peroneus longus autograft can be recommended as a superior graft to hamstring tendon in single-bundle ACL reconstruction

PURPOSE

A peroneus longus tendon autograft is used in many orthopaedic procedures and it is biomechanically comparable to a hamstring tendon autograft. Despite its potential, there are few studies that have evaluated the use of the peroneus longus tendon in ACL reconstruction. The aim of this study was to compare the clinical outcome and donor site morbidity of ACL reconstruction with hamstring tendon autografts versus peroneus longus tendon autografts in patients with an isolated ACL injury.

METHODS

Patients who underwent isolated single-bundle ACL reconstruction were allocated to two groups (hamstring and peroneus longus) and observed prospectively. Graft diameter was measured intraoperatively. Functional scores (IKDC, modified Cincinnati and Lysholm scores) were recorded preoperatively and 1 year after surgery. Donor site morbidities were assessed with thigh circumference measurements and ankle scoring with the AOFAS and FADI.

RESULTS

Fifty-two patients (hamstring n = 28, peroneus n = 24) met the inclusion criteria. The peroneus longus graft diameter (8.8 ± 0.7 mm) was significantly larger than the hamstring diameter (8.2 ± 0.8 mm) (p = 0.012). There were no significant differences between the pre- and 1-year postoperative score between the hamstring and peroneus longus groups in the IKDC (n.s), modified Cincinnati (n.s), and Lysholm (n.s). The mean for the AOFAS was 97.3 ± 4.2 and for the FADI 98 ± 3.4 in the peroneus longus group, with a significant decrease in thigh circumference in the hamstring group (p = 0.002).

CONCLUSION

Anterior cruciate ligament reconstruction with peroneus longus autografts produces a functional score (IKDC, modified Cincinnati, Lysholm) comparable to that of hamstring autografts at a 1-year follow-up, with the advantages of larger graft diameter, less thigh hypotrophy and excellent ankle function based on AOFAS and FADI scores.

LEVEL OF EVIDENCE

Prospective cohort study, Level II.

Knee-related quality of life, functional results and osteoarthritis at a minimum of 20 years' follow-up after anterior cruciate ligament reconstruction

BACKGROUND

Few studies in the literature show results with more than 20 years of follow-up after anterior cruciate ligament reconstruction (ACLR). The main purpose of this retrospective study was to describe knee-specific quality of life, functional results and prevalence of osteoarthritis (OA) of the knee in patients with ACLR using bone-patellar tendon-bone (BPTB) autograft with ultra-long-term follow-up.

METHODS

Prospective analyzed data included demographics, meniscus status, radiographic OA, KT-1000 arthrometer measurements and physical examinations. KOOS, Lysholm and IKDC subjective surveys were conducted. Multivariate and univariate logistic models were used to determine the effect of potential predictors of OA and symptomatic knees.

RESULTS

Seventy-two knees were included at a median follow-up of 22 (IQR 21-25) years postoperatively. Radiographic scores were normal in 15%, nearly normal in 57%, abnormal in 18% and severely abnormal in 10%. Multivariate analysis showed that the predictive factor for the presence of OA in the long-term was an associated meniscal lesion; patients with meniscal lesions were 3.9 times as likely to develop OA in comparison with those without meniscal injury. The subjective scores were progressively and significantly lower as the level of OA was greater.

CONCLUSION

At a median of 22 years of follow-up, this study shows that patellar tendon autograft ACL reconstruction provides good clinical outcomes, with clinically objective knee stability and a 28% prevalence of OA. Additionally, we identified that meniscal injury at time of surgery was an independent predictor of OA.

LEVEL OF EVIDENCE

Level IV; case series.

Posterior Cruciate Ligament reconstruction with peroneus longus tendon graft: 2-Years follow-up

Background

Several study that evaluate the usage of peroneus longus tendon (PLT) autograft in Anterior Cruciate Ligament reconstruction shows good result. Regardless the potential, there was no study about the use of PLT autograft in Posterior Cruciate Ligament (PCL) reconstruction. The purpose of this study is to evaluate the functional outcome and donor site morbidity after single bundle PCL reconstruction using PLT autograft.

Methods

Patient who met inclusion criteria, enrolled to this study and underwent single bundle PCL reconstruction using PL tendon autograft. Clinical outcomes were assessed with International Knee Documentation Committee (IKDC), Modified Cincinnati scoring systems, Lysholm score, and Serial hop test (single hop test and triple hop test) 2-year after surgery. Donor site morbidity was assessed with Foot and Ankle Disability Index (FADI) and American Orthopaedic Foot and Ankle (AOFAS) scoring system.

Results

Fifteen patients fulfilled the inclusion criteria (11 males and 4 females). PLT graft diameters were 7.5–10 mm (mean: 8.30 ± 0.65 mm). Significant increase of functional score (p < 0.05) were found two years after surgery. Mean score of IKDC was 47.58 ± 11.75 pre-operative; 78.17 ± 4.52 post-operative, Modified Cincinnati was 48.86 ± 12.22 pre-operative; 79.00 ± 4.82 post-operative, Lysholm score was 49.26 ± 11.54 pre-operative; 80.20 ± 5.04 post-operative. FADI and AOFAS at donor site ankle was 93.00 ± 3.04 and 93.26 ± 4.20, respectively. Serial hop test showed good result.

Conclusion

PCL reconstruction using peroneus longus tendon autograft shows good functional outcome of the knee based on IKDC, Modified Cincinnati, Lysholm score, with preservation of ankle function based on AOFAS and FADI score at 2-years follow-up.

Failure to Return to Preinjury Activity Level after Hamstring Anterior Cruciate Ligament Reconstruction: Factors Involved and Considerations in Goal Setting

BACKGROUND

Recent interest in the return to sports, following anterior cruciate ligament reconstruction, has focused on the influence of psychological factors. However, many factors contribute to this endpoint. This study aimed to investigate the ability of nonprofessional athletes to return alongside the reasons for failure.

MATERIALS AND METHODS

We retrospectively studied 101 postreconstruction patients with followup in excess of 12 months. All patients underwent hamstring autograft anterior cruciate reconstruction. The Cincinnati Sports Activity Scale was used to define activity level preinjury, postinjury, and postreconstruction. Structured questionnaires were used to identify factors in those who did not return to the same level.

RESULTS

Seventy percent of patients returned to their preinjury activity score. Of the 30% of patients who failed, age, reconstruction type, and associated pathology were unrelated. However, reconstruction within 6 months of injury resulted in increased return to preinjury score (P < 0.05). Failure was associated with continued knee symptoms (57%), lifestyle changes (27%), anxiety (27%), fear (23%), and other musculoskeletal problems (10%). Considerable interplay was found between these factors. Failure to return was associated with increased further surgery, but this was successful in only one-third of patients.

CONCLUSION

Psychological factors are important (and may require targeted input), but return-to-sport is multifactorial. Ongoing symptoms may prompt further surgery, but this is frequently unsuccessful in achieving return. Patient-specific goals should be sought and revisited throughout the rehabilitation program. Acknowledging psychological barriers, in those aiming to return to the same level, may help achieve this goal. In other patients, success may be return to a desired lower level. Understanding the patient's expectations is important in goal setting.

Three-dimensional isotropic magnetic resonance imaging can provide a reliable estimate of the native anterior cruciate ligament insertion site anatomy

PURPOSE

This study quantified the error in anterior cruciate ligament (ACL) insertion site location and area estimated from three-dimensional (3D) isotropic magnetic resonance imaging (MRI) by comparing to native insertion sites determined via 3D laser scanning.

METHODS

Isotropic 3D DESS MRI was acquired from twelve fresh-frozen, ACL-intact cadaver knees. ACL insertion sites were manually outlined in each MRI slice, and the resulting contours combined to determine the 3D insertion site shape. Specimens were then disarticulated, and the boundaries of the ACL insertion sites were digitized using a high-accuracy laser scanner. MRI and laser scan insertion sites were co-registered to determine the percent overlapping area and difference in insertion centroid location.

RESULTS

Femoral ACL insertion site area averaged 112.7 ± 17.9 mm² from MRI and 109.7 ± 10.9 mm² from laser scan (p = 0.345). Tibial insertion area was 134.7 ± 22.9 mm² from MRI and 135.2 ± 15.1 mm² from laser scan (p = 0.881). Percentages of overlapping area between modalities were 82.2 ± 10.2% for femurs and 81.0 ± 9.0% for tibias. The root-mean-square differences for ACL insertion site centroids were 1.87 mm for femurs and 2.49 mm for tibias. The MRI-estimated ACL insertion site centroids were biased on average 0.6 ± 1.6 mm proximally and 0.3 ± 1.9 mm posteriorly for femurs, and 0.3 ± 1.1 mm laterally and 0.5 ± 1.5 mm anteriorly for tibias.

CONCLUSION

Errors in ACL insertion site location and area estimated from 3D-MRI were determined via comparison with a high-accuracy 3D laser scanning. Results indicate that MRI can provide estimates of ACL insertion site area and centroid location with clinically applicable accuracy. MRI-based assessment can provide a reliable estimate of the native ACL anatomy, which can be helpful for surgical planning as well as assessment of graft tunnel placement.

Restoring tibiofemoral alignment during ACL reconstruction results in better knee biomechanics

PURPOSE

Anterior cruciate ligament (ACL) reconstruction (ACLR) aims to restore normal knee joint function, stability and biomechanics and in the long term avoid joint degeneration. The purpose of this study is to present the anatomic single bundle (SB) ACLR that emphasizes intraoperative correction of tibiofemoral subluxation that occurs after ACL injury. It was hypothesized that this technique leads to optimal outcomes and better restoration of pathological tibiofemoral joint movement that results from ACL deficiency (ACLD).

METHODS

Thirteen men with unilateral ACLD were prospectively evaluated before and at a mean follow-up of 14.9 (SD = 1.8) months after anatomic SB ACLR with bone patellar tendon bone autograft. The anatomic ACLR replicated the native ACL attachment site anatomy and graft orientation. Emphasis was placed on intraoperative correction of tibiofemoral subluxation by reducing anterior tibial translation (ATT) and internal tibial rotation. Function was measured with IKDC, Lysholm and the Tegner activity scale, ATT was measured with the KT-1000 arthrometer and tibial rotation (TR) kinematics were measured with 3Dmotion analysis during a high-demand pivoting task.

RESULTS

The results showed significantly higher TR of the ACL-deficient knee when compared to the intact knee prior to surgery (12.2° ± 3.7° and 10.7° ± 2.6° respectively, P = 0.014). Postoperatively, the ACLR knee showed significantly lower TR as compared to the ACL-deficient knee (9.6°±3.1°, P = 0.001) but no difference as compared to the control knee (n.s.). All functional scores were significantly improved and ATT was restored within normal values (P < 0.001).

CONCLUSIONS

Intraoperative correction of tibiofemoral subluxation that results after ACL injury is an important step during anatomic SB ACLR. The intraoperative correction of tibiofemoral subluxation along with the replication of native ACL anatomy results in restoration of rotational kinematics of ACLD patients to normal levels that are comparable to the control knee. These results indicate that the reestablishment of tibiofemoral alignment during ACLR may be an important step that facilitates normal knee kinematics postoperatively.

LEVEL OF EVIDENCE

Level II, prospective cohort study.

Editorial Commentary: Using Computer Simulations to Predict Functional Outcome After Surgery

Computer simulations of surgical procedures can be used to predict functional outcome after surgery. To impact clinical decision making, the simulations must be an accurate representation of the in vivo condition.

Radiographic femoral bicondylar width predicts anterior cruciate ligament insertion site sizes

PURPOSE

The purpose of this study was to determine whether radiographic femoral bicondylar width predicts intra-operative anterior cruciate ligament (ACL) insertion site sizes.

METHODS

Seventy-three consecutive patients (39 males and 34 females; mean age 25.2 years ± 10.2) who underwent anatomic ACL reconstruction were retrospectively reviewed. Femoral condyle width was measured using a pre-operative anteroposterior (AP) radiograph of the operative knee. Lines were drawn through the anatomic axis of the femur, as well as perpendicularly through the condyles. Bicondylar width was measured as the maximum width across both the medial and lateral femoral condyles utilizing this perpendicular line. The ACL insertion site lengths (in the AP direction) of both the tibia and the femur were measured intra-operatively using a commercially available arthroscopic ruler.

RESULTS

The average bicondylar width was significantly smaller for females compared to males (p < 0.05). The average tibial and femoral insertion site sizes were significantly smaller for females compared to males (p < 0.05). Regression analysis predicted tibial (r ² = 0.88) and femoral (r ² = 0.90) insertion site sizes based on femoral bicondylar width measurements.

CONCLUSION

A simple radiographic measurement of femoral bicondylar width can predict intra-operative tibial and femoral insertion site sizes, which has the potential to assist surgeons in performing individualized ACL reconstruction in cases where MRI scan is unavailable.

LEVEL OF EVIDENCE

IV.

Fibrin clot prevents bone tunnel enlargement after ACL reconstruction with allograft

PURPOSE

Bone tunnel enlargement is a feared complication after ACL reconstruction. The aim of this study was to evaluate whether adding a fibrin clot to the allograft for anatomic single-bundle ACL reconstruction would reduce tunnel widening.

METHODS

Fifty patients who underwent anatomic single-bundle ACL reconstruction were included. Twenty-five patients received an allograft alone, and 25 patients received an allograft with fibrin clot. All patients underwent standard plain anteroposterior and lateral radiographs of the operated knee immediately after surgery and at 1-year follow-up. The size of the tunnels was measured at both time points to calculate tunnel widening. Tunnel widening at 1 year was compared between the allograft and the allograft + fibrin clot group.

RESULTS

There was significantly less tunnel widening in the allograft + fibrin clot group for the femoral tunnel width in the middle and distal portion of the tunnel and for the tibial tunnel width in the proximal and distal portions, as compared to the allograft only group.

CONCLUSION

Adding a fibrin clot to the allograft in anatomic single-bundle ACL reconstruction reduces the amount of tunnel widening at 1-year follow-up. Reducing tunnel widening may positively affect outcomes after ACL surgery and may prevent inadequate bone stock during ACL revision procedures.

LEVEL OF EVIDENCE

Case-control study, Level III.

Knee joint kinematics after dynamic intraligamentary stabilization: cadaveric study on a novel anterior cruciate ligament repair technique

PURPOSE

Dynamic intraligamentary stabilization (DIS) has been introduced for the repair of acute anterior cruciate ligament (ACL) tears as an alternative to delayed reconstruction. The aim of the present study was to compare knee joint kinematics after DIS to those of the ACL-intact and ACL-deficient knee under simulated Lachman/KT-1000 and pivot-shift tests. We hypothesized that DIS provides knee joint kinematics equivalent to an intact ACL.

METHODS

With the use of a robotic knee simulator, knee kinematics were determined in simulated Lachman/KT-1000 and pivot-shift tests at 0°, 15°, 30°, 60°, and 90° of flexion in eight cadaveric knees under the following conditions: (1) intact ACL, (2) ACL deficiency, (3) DIS with a preload of 60 N, and (4) DIS with a preload of 80 N. Statistical analyses were performed using two-factor repeated-measures analysis of variance. The significance level was set at a p value of <0.05.

RESULTS

After DIS with a preload of either 60 N or 80 N, the anterior translation was significantly reduced in the simulated Lachman/KT-1000 and pivot-shift tests when compared to the ACL-deficient knee (p < 0.05). No significant differences were observed between the DIS reconstruction with a preload of 80 N and the intact ACL with regard to anterior laxity in either test. However, DIS with a preload of only 60 N was not able to restore knee joint kinematics to that of an intact knee in all degrees of flexion.

CONCLUSION

DIS with a preload of 80 N restores knee joint kinematics comparable to that of an ACL-intact knee and is therefore capable of providing knee joint stability during ACL healing. DIS therefore provides a new technique for primary ACL repair with superior biomechanical properties in comparison with other techniques that have been described previously, although further clinical studies are required to determine its usefulness in clinical settings.

Ligament-Derived Stem Cells: Identification, Characterisation, and Therapeutic Application

Ligament is prone to injury and degeneration and has poor healing potential and, with currently ineffective treatment strategies, stem cell therapies may provide an exciting new treatment option. Ligament-derived stem cell (LDSC) populations have been isolated from a number of different ligament types with the majority of studies focussing on periodontal ligament. To date, only a few studies have investigated LDSC populations in other types of ligament, for example, intra-articular ligaments; however, this now appears to be a developing field. This literature review aims to summarise the current information on nondental LDSCs including in vitro characteristics of LDSCs and their therapeutic potential. The stem cell niche has been shown to be vital for stem cell survival and function in a number of different physiological systems; therefore, the LDSC niche may have an impact on LDSC phenotype. The role of the LDSC niche on LDSC viability and function will be discussed as well as the therapeutic potential of LDSC niche modulation.

Biologic Treatments for Sports Injuries II Think Tank-Current Concepts, Future Research, and Barriers to Advancement, Part 1: Biologics Overview, Ligament Injury, Tendinopathy

Biologic therapies, including stem cells, platelet-rich plasma, growth factors, and other biologically active adjuncts, have recently received increased attention in the basic science and clinical literature. At the 2015 AOSSM Biologics II Think Tank held in Colorado Springs, Colorado, a group of orthopaedic surgeons, basic scientists, veterinarians, and other investigators gathered to review the state of the science for biologics and barriers to implementation of biologics for the treatment of sports medicine injuries. This series of current concepts reviews reports the summary of the scientific presentations, roundtable discussions, and recommendations from this think tank.

Failure Rate and Clinical Outcomes of Anterior Cruciate Ligament Reconstruction Using Autograft Hamstring Versus a Hybrid Graft

PURPOSE

To compare the revision rate and subjective outcome measures of autograft hamstring versus a soft tissue hybrid graft combining both autograft hamstring and tibialis allograft for isolated anterior cruciate ligament (ACL) reconstruction.

METHODS

A single-center retrospective, nonrandomized, comparative study of isolated ACL reconstruction revision rates for subjects who underwent arthroscopic reconstruction of the ACL using autograft hamstring or a soft tissue hybrid graft using both autograft hamstring and tibialis allograft was performed. Patients with isolated ACL tears were included and underwent anatomic single-bundle reconstruction using an independent tunnel drilling technique and a minimum of 24 months' follow-up. The primary outcome assessed was the presence or absence of ACL rerupture. Secondary clinical outcomes consisted of the International Knee Documentation Committee, University of California at Los Angeles (UCLA) ACL quality of life assessment, and the visual analog pain scale.

RESULTS

Between February 2010 and April 2013, 95 patients with isolated ACL tears between ages 18 and 40 met the inclusion criteria and were enrolled. Seventy-one autograft hamstring and 24 soft tissue hybrid graft ACL reconstructions were performed during the course of this study. The follow-up period was 24 to 32 months (mean 26.9 months). There were no statistically significant differences in patient demographics or Outerbridge classification. No statistically significant differences in ACL retears (5.6% auto, 4.2% hybrid; P = .57) were found between groups. Clinical International Knee Documentation Committee and UCLA ACL quality of life assessment improvement scores revealed no statistically significant differences in autograft and hybrid graft reconstructions (41 ± 11, 43 ± 13; P = .65) (38 ± 11, 40 ± 10; P = .23). The mean pain level decreased from 8.1 to 2.8 in the autograft group and 7.9 to 2.5 in the hybrid group (P = .18).

CONCLUSIONS

The use of a hybrid soft tissue graft has a comparable rerupture rate and clinical outcome to ACL reconstruction using autograft hamstring.

LEVEL OF EVIDENCE

Level III, retrospective comparative study.

Primary Repair of Tibial-Sided Avulsion of the Anterior Cruciate Ligament

Lesions of the anterior cruciate ligament (ACL) are common; the current gold standard of treatment for such lesions is ACL reconstruction. Tibial-sided soft-tissue avulsion is a rare subtype of ACL injuries. Unlike femoral-sided ACL repair, surgery for acute tibial-sided ACL ruptures has been neither reported nor described. This technical note presents a method for primary anatomic ACL reinsertion for an acute distal soft-tissue avulsion-type ACL injury, using a transosseous pull-out repair technique. Our technique, as an alternative to reconstruction, has the potential to enhance healing due to marrow stimulation (tibial tunneling). It also preserves the native insertion site and proprioceptive function, which may, in turn, reduce the risk of post-traumatic osteoarthritis.

Surgical Technique Trends in Primary ACL Reconstruction from 2007 to 2014

BACKGROUND

The surgical technique for anterior cruciate ligament (ACL) reconstruction has evolved as a result of improved understanding of ligament biomechanics, anatomy, device development, and failed reconstructions. Studies on surgical technique preferences have been limited to surgeon surveys, which are subject to selection and recall bias. The purpose of this study was to evaluate ACL reconstruction surgical technique and yearly revision rate trends in a community-based setting.

METHODS

A population-based epidemiological study was conducted using data on primary ACL reconstruction procedures registered in an ACL reconstruction registry from 2007 to 2014. Changes in the incidence rates of different types of femoral tunnel drilling methods, different types of grafts and graft fixation, and revisions were studied. Adjusted incidence rate ratios (IRRs) are provided.

RESULTS

Of the 21,686 ACL reconstructions studied, 72.4% were performed by sports medicine fellowship-trained surgeons. The incidence rate of femoral tunnel drilling via a tibial tunnel decreased at an adjusted rate of 26% per year (IRR = 0.74, 95% confidence interval [CI] = 0.71 to 0.78), from 56.4% to 17.6% during the study period. The incidence rate of medial portal drilling increased from 41.3% to 65.1% at an adjusted rate of 11% per year (IRR = 1.11, 95% CI = 1.09 to 1.13), and the incidence rate of drilling through a lateral approach increased from 2.3% to 17.3% at an adjusted rate of 53% per year (IRR = 1.53, 95% CI = 1.39 to 1.67). There was no change in the use of hamstring autograft, bone-patellar tendon-bone autograft, or tibial tendon allograft. Use of first-generation bioabsorbable femoral and tibial fixation decreased for all graft types. For soft-tissue grafts, usage of suspensory metal femoral fixation increased 12% to 13% per year (IRR = 1.12, 95% CI = 1.09 to 1.15 for tibial tendon grafts; IRR = 1.13, 95% CI = 1.10 to 1.15 for hamstring grafts). For bone-patellar tendon-bone autografts, the use of femoral fixation with interference biocomposite screws increased 7% per year (IRR = 1.07, 95% CI = 1.04 to 1.10). On the tibial side, utilization of biocomposite screws increased for all graft types. No association was found between revision rate and the year of the primary operation.

CONCLUSIONS

Surgeons changed their femoral tunnel drilling technique over the study period, whereas the incidence rates of specific graft utilization remained stable. There has been a shift away from first-generation bioabsorbable fixation and increasing use of biocomposite fixation across all graft types. Early cumulative revision rates remained stable.

Sport and early osteoarthritis: the role of sport in aetiology, progression and treatment of knee osteoarthritis

Sports activities are considered favourable for general health; nevertheless, a possible influence of sports practice on the development of early osteoarthritis (OA) is a cause for concern. A higher incidence of OA in knees and ankles of former high-impact sports players than in those of the normal population has been shown and it is still debatable whether the cause is either to be recognized generically in the higher number of injuries or in a joint overload. The possibility to address knee OA in its early phases may be strictly connected to the modification of specific extrinsic or intrinsic factors, related to the patient in order to save the joint from further disease progression; these include sport practice, equipment and load. Non-surgical therapies such as continuative muscles reinforce and training play a strong role in the care of athletes with early OA, particularly if professional. There is an overall agreement on the need of an early restoring of a proper meniscal, ligament and cartilage integrity in order to protect the knee and resume sports safely, whereas alignment is a point still strongly debatable especially for professional athletes. Remaining questions still to be answered are the risks of different sports in relation to one another, although an actual protective effect of low-impact sports, such as walking, swimming or cycling, has been recognized on the appearance or worsening of OA, the effect of continuing or ceasing to practice a sport on the natural history of early OA, and even following appropriate treatment is still unknown.

Anterior Cruciate Ligament Reconstruction With Autologous Hamstring: Can Preoperative Magnetic Resonance Imaging Accurately Predict Graft Diameter?

Background:

Recent clinical investigations have identified inadequate autograft hamstring graft diameter (<8 mm) to be predictive of failure after reconstruction of the anterior cruciate ligament (ACL).

Purpose/Hypothesis:

The objective of this study was to determine the utility of preoperative magnetic resonance imaging (MRI) variables of the hamstring tendons for the prediction of graft diameter at the time of surgery. The hypothesis was that cross-sectional area (CSA) of the hamstring tendon measured on MRI could accurately predict graft diameter, and threshold measurements could be established to predict graft diameter at the time of surgery.

Study Design:

Cohort study (diagnosis); Level of evidence, 2.

Methods:

A total of 84 consecutive skeletally mature patients prospectively enrolled in our ACL reconstruction patient registry were identified for study purposes. Patients were included if they underwent an MRI of the affected knee at our institution prior to ACL reconstruction with hamstring (HT) autograft. Graft preparation was performed via a standard quadrupled hamstring technique after harvesting both the gracilis and semitendinosus (4-GST). The smallest diameter end of the HT autograft was then utilized for measurement analysis. Total CSA was calculated for both hamstring tendons using the “region of interest tool” on the corresponding proton density–weighted axial image of the knee at the widest condylar dimension. Three independent reviewers measured the MRI scans so that intra- and interrater reliability of the measurements could be determined. A trend analysis was then undertaken to establish correlations between the MRI CSA and graft diameter. Predictive analysis was then performed to establish threshold MRI measurement values for specific graft diameters and determine whether any patient-specific factors would affect graft diameter (age, sex, and body mass index).

Results:

Mean patient age at the time of surgery was 36 years (range, 11-57 years). Intra- and interrater reliability measurements achieved near-perfect agreement for CSA measurements, with intraclass correlation coefficients (ICCs) of 0.994 and 0.932, respectively. Trend analysis demonstrated that increasing CSA correlated well with increasing overall diameter of the graft (P < .001). Receiver operating characteristic (ROC) curves were generated to evaluate threshold CSA measurements for various graft diameters. Maximum sensitivity values of 21.64, 25.25, and 28.256 mm² were established for the respective graft diameters of 8, 9, and 10 mm in the 4-GST group. Independent patient factors of younger age, shorter stature, and female sex were significantly associated with graft diameter (P = .019, .034, and .028, respectively).

Conclusion:

Preoperative MRI can be used to accurately predict quadrupled hamstring autograft diameter at the time of surgery. A total cross-sectional area of >22 mm² can reliably provide a graft diameter of >8 mm at the time of surgery.

Local delivery of controlled-release simvastatin to improve the biocompatibility of polyethylene terephthalate artificial ligaments for reconstruction of the anterior cruciate ligament

The Ligament Advanced Reinforcement System has recently been widely used as the primary graft of choice in anterior cruciate ligament (ACL) reconstruction. But the biological graft-bone healing still remains a problem. Previous studies have shown that simvastatin (SIM) stimulates bone formation. The objective of this study was to investigate whether surface coating with collagen containing low-dose SIM microsphere could enhance the surface biocompatibility of polyethylene terephthalate (PET) artificial ligaments to accelerate graft-to-bone healing. The in vitro studies demonstrated that bone marrow stromal cells on the collagen-coated PET scaffolds (COL/PET) and simvastatin/collagen-coated PET scaffolds (SIM/COL/PET) proliferated vigorously. Compared with the PET group and the COL/PET group, SIM could induce bone marrow stromal cells' osteoblastic differentiation, high alkaline phosphatase activity, more mineralization deposition, and more expression of osteoblast-related genes, such as osteocalcin, runt-related transcription factor 2, bone morphogenetic protein-2, and vascular endothelial growth factor, in the SIM/COL/PET group. In vivo, rabbits received ACL reconstruction with different scaffolds. Histological analysis demonstrated that graft-bone healing was significantly greater with angiogenesis and osteogenesis in the SIM/COL/PET group than the other groups. In addition, biomechanical testing at the eighth week demonstrated a significant increase in the ultimate failure load and stiffness in the SIM/COL/PET group. The low dose of SIM-sustained release from SIM/COL/PET promoted the graft-bone healing via its effect on both angiogenesis and osteogenesis. This study suggested that collagen containing low-dose SIM microsphere coating on the surface of PET artificial ligaments could be potentially applied for ACL reconstruction.

Healing of the Acutely Injured Anterior Cruciate Ligament: Functional Treatment with the ACL-Jack, a Dynamic Posterior Drawer Brace

Background. The injured anterior cruciate ligament (ACL) has a limited healing capacity leading to persisting instability. Hypothesis/Purpose. To study if the application of a brace, producing a dynamic posterior drawer force, after acute ACL injury reduces initial instability. Study Design. Cohort study. Methods. Patients treated with the ACL-Jack brace were compared to controls treated with primary ACL reconstruction und controls treated nonsurgically with functional rehabilitation. Measurements included anterior laxity (Rolimeter), clinical scores (Lysholm, Tegner, and IKDC), and MRI evaluation. Patients were followed up to 24 months. Results. Patients treated with the ACL-Jack brace showed a significant improvement of anterior knee laxity comparable to patients treated with ACL reconstruction, whereas laxity persisted after nonsurgical functional rehabilitation. The failure risk (secondary reconstruction necessary) of the ACL-Jack group was however 21% (18 of 86) within 24 months. Clinical scores were similar in all treatment groups. Conclusion. Treatment of acute ACL tears with the ACL-Jack brace leads to improved anterior knee laxity compared to nonsurgical treatment with functional rehabilitation.

Hydroxyapatite-doped polycaprolactone nanofiber membrane improves tendon-bone interface healing for anterior cruciate ligament reconstruction

Hamstring tendon autograft is a routine graft for anterior cruciate ligament (ACL) reconstruction. However, ways of improving the healing between the tendon and bone is often overlooked in clinical practice. This issue can be addressed by using a biomimetic scaffold. Herein, a biomimetic nanofiber membrane of polycaprolactone/nanohydroxyapatite/collagen (PCL/nHAp/Col) is fabricated that mimics the composition of native bone tissue for promoting tendon–bone healing. This membrane has good cytocompatibility, allowing for osteoblast cell adhesion and growth and bone formation. As a result, MC3T3 cells reveal a higher mineralization level in PCL/nHAp/Col membrane compared with PCL membrane alone. Further in vivo studies in ACL reconstruction in a rabbit model shows that PCL/nHAp/Col-wrapped tendon may afford superior tissue integration to nonwrapped tendon in the interface between the tendon and host bone as well as improved mechanical strength. This study shows that PCL/nHAp/Col nanofiber membrane wrapping of autologous tendon is effective for improving tendon healing with host bone in ACL reconstruction.

Temperature-controlled continuous cold flow device versus traditional icing regimen following anterior cruciate ligament reconstruction: a prospective randomized comparative trial

INTRODUCTION

Anterior cruciate ligament (ACL) reconstruction requires an intensive rehabilitation program to be completely successful. Cryotherapy has been described to be helpful in reducing post-operative pain and edema. Aim of this prospective randomized study is to compare two homogeneous groups of patients, one receiving traditional icing regimen and the other a temperature-controlled continuous cold flow device, in post-operative setting after ACL reconstruction.

MATERIALS AND METHODS

Forty-seven patients treated for ACL reconstruction using "over the top" technique were enrolled for this study. All patients received the same elastocompressive bandage. Regarding the coolant device, 23 patients were randomized to temperature-controlled continuous cold flow device (Hilotherm® group) and 24 patients were randomized to receive ice bag (control group). The two groups were homogenous for pre-operative (age, sex, and time "lesion to surgery") and intra-operative parameters (duration of the procedure, meniscectomy, and chondral damage). NRS (numeric rating scale), blood loss, knee volume increase at three established sites, ROM, and pain killers consumption were assessed. The subjective evaluation of the device including practicality and usefulness of the device was investigated.

RESULTS

Hilotherm group resulted in lower pain perception (NRS), blood loss, knee volume increase at the patellar apex and 10 cm proximal to the superior patellar pole, and higher range of motion (p < 0.05) in the first post-operative day. No difference in pain killers consumption was noted. Hilotherm device was considered "comfortable" and "useful" by the majority of patients.

CONCLUSIONS

Hilotherm group showed significant better results in first post-operative day. Further studies with higher number of patients and longer follow-up are required to assess the beneficial effects on rehabilitation and the cost-effectiveness of the routinely use of this device.

LEVEL OF EVIDENCE

II.

Does Double-Bundle Anterior Cruciate Ligament Reconstruction Improve Postoperative Knee Stability Compared With Single-Bundle Techniques? A Systematic Review of Overlapping Meta-analyses

PURPOSE

Multiple meta-analyses of randomized controlled trials, the highest available level of evidence, have been conducted to determine whether double-bundle (DB) or single-bundle (SB) anterior cruciate ligament reconstruction (ACL-R) provides superior clinical outcomes and knee stability; however, results are discordant. The purpose of this study was to conduct a systematic review of meta-analyses comparing SB and DB ACL-R to discern the cause of the discordance and to determine which of these meta-analyses provides the current best available evidence.

METHODS

We evaluated available scientific support for SB as compared with DB ACL-R by systematically reviewing the literature for published meta-analyses. Data on patient clinical outcomes and knee stability (as measured by KT arthrometry and pivot-shift testing) were extracted. Meta-analysis quality was judged using the Oxman-Guyatt and Quality of Reporting of Meta-analyses systems. The Jadad algorithm was then applied to determine which meta-analyses provided the highest level of evidence.

RESULTS

Nine meta-analyses were included, of which 3 included Level I Evidence and 6 included both Level I and Level II Evidence. Most studies found significant differences favoring DB reconstruction on pivot-shift testing, KT arthrometry measurement of anterior tibial translation, and International Knee Documentation Committee objective grading. Most studies detected no significant differences between the 2 techniques in subjective outcome scores (Tegner, Lysholm, and International Knee Documentation Committee subjective), graft failure, or complications. Oxman-Guyatt and Quality of Reporting of Meta-analyses scores varied, with 2 studies exhibiting major flaws (Oxman-Guyatt score <3). After application of the Jadad decision algorithm, 3 concordant high-quality meta-analyses were selected, with each concluding that DB ACL-R provided significantly better knee stability (by KT arthrometry and pivot-shift testing) than SB ACL-R but no advantages in clinical outcomes or risk of graft failure.

CONCLUSIONS

The current best available evidence suggests that DB ACL-R provides better postoperative knee stability than SB ACL-R, whereas clinical outcomes and risk of graft failure are similar between techniques.

LEVEL OF EVIDENCE

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

State-of-the-art anterior cruciate ligament tears: A primer for primary care physicians

The purpose of this article is to provide primary care physicians and other members of the medical community with an updated, general review on the subject of anterior cruciate ligament (ACL) tears. We aim to enhance awareness of these injuries and to prepare those practicing in the primary care setting to address these injuries. Because ACL injuries are quite common, it is very likely that a primary care physician will encounter these injuries and need to address them acutely. The current literature is replete with new concepts and controversies regarding ACL injuries, and this article provides a concise review for our target audience in regard to the care of a patient with an ACL injury. This article is composed of an overview with current epidemiologic data, basic anatomy and physiology, clinical presentation, physical examination findings, imaging modalities, and treatment options. After reading this short article, a medical care provider should understand ACL injuries and their appropriate management.

Prevention of graft-tunnel mismatch during anatomical anterior cruciate ligament reconstruction using a bone-patellar tendon-bone graft

Graft-tunnel mismatch of the bone-patellar tendon-bone (BPTB) graft is a major concern during anatomical anterior cruciate ligament (ACL) reconstruction if the femoral tunnel is positioned using a far medial portal technique, as the femoral tunnel tends to be shorter compared with that positioned using a transtibial portal technique. This study describes an accurate method of calculating the ideal length of bone plugs of a BPTB graft required to avoid graft–tunnel mismatch during anatomical ACL reconstruction using a far medial portal technique of femoral tunnel positioning.

Based on data obtained intra-operatively from 60 anatomical ACL reconstruction procedures, we calculated the length of bone plugs required in the BPTB graft to avoid graft–tunnel mismatch. When this was prevented in all the 60 cases, we found that the mean length of femoral bone plug that remained in contact with the interference screw within the femoral tunnel was 14 mm (12 to 22) and the mean length of tibial bone plug that remained in contact with the interference screw within the tibial tunnel was 23 mm (18 to 28). These results were used to validate theoretical formulae developed to predict the required length of bone plugs in BPTB graft during anatomical ACL reconstruction using a far medial portal technique.

Cite this article: Bone Joint J 2015;97-B:324–8.

Closure of patellar tendon defect in anterior cruciate ligament reconstruction with bone-patellar tendon-bone autograft: systematic review of randomized controlled trials

PURPOSE

This study aimed to systematically review the highest level of evidence on anterior cruciate ligament (ACL) reconstruction with bone-patellar tendon-bone (BPTB) autografts with patellar tendon defect closure versus no closure after surgery.

METHODS

We performed a systematic review of multiple medical databases using Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Level I and Level II randomized controlled trials comparing patellar tendon defect closure to no closure during ACL reconstruction with BPTB autografts were included. Two independent reviewers analyzed all studies. Descriptive statistics were calculated. Study methodological quality was analyzed using the Modified Coleman Methodology Score (MCMS) and Jadad scale.

RESULTS

Four studies with a combined 221 patients (154 male patients and 67 female patients) with an average age of 26.6 ± 2.4 years (range, 17 to 54 years) were included. All studies randomized patients before surgery into ACLR with BPTB autografts either with patellar tendon defect closure or without closure. There were no differences in clinical outcomes (Lysholm score, Tegner scale, International Knee Documentation Committee [IKDC] classification, modified Larsen score, and Lauridsen rating) between groups. There were no significant differences in knee pain between groups. All studies reported imaging findings of the patellar tendon defect, with 2 studies showing no difference in appearance between groups, one study showing excessive scar formation with defect repair, and one study showing improved restoration of normal tendon appearance with defect repair. The overall quality of the studies was poor, with all studies scoring less than 46 (average, 40.5 ± 4.7) on the MCMS and scoring 1 on the Jadad scale.

CONCLUSIONS

Based on this systematic review of 4 randomized trials, there are no statistically significant or clinically relevant differences in outcomes between patients who have the patellar tendon defect closed and those who have it left open after ACLR with BPTB autografts. The methodology of the included studies limits the interpretation of the data, as evidenced by low MCMS and Jadad scores.

LEVEL OF EVIDENCE

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

Anatomic Double-Bundle Reinsertion After Acute Proximal Anterior Cruciate Ligament Injury Using Knotless PushLock Anchors

Direct anterior cruciate ligament (ACL) repair has been described with different suture techniques after acute ACL injury, but these procedures showed high failure rates. Recent studies, however, led to a better understanding of the biology of primary ACL healing. This article describes a novel technique combining the "healing response technique" with primary anatomic double-bundle ACL reinsertion after an acute proximal ACL tear using nonabsorbable No. 2 FiberWire (Arthrex, Naples, FL) and PushLock knotless suture anchors (Arthrex). We recommend this technique for patients with acute proximal avulsion-type ACL injuries. Postoperatively, we recommend a knee brace locked in full extension for at least 4 weeks to ensure adequate immobilization and then to increase knee flexion slowly over the next 4 weeks for subsequent healing of the ACL repair. Our technique combines anatomic positioning and reinsertion of the ACL bundles with microfracturing of the region delivering stem cells and growth factors to the repaired ACL, creating optimal conditions for the healing period. In certain cases this technique might be an alternative to conventional ACL reconstruction with autograft or allograft tendons.