Is anterolateral ligament rupture a reason for persistent rotational instability after anterior cruciate ligament reconstruction?

Background

The aim of the present study was to evaluate the clinical role of anterolateral ligament (ALL) rupture and its impact on rotational stability by comparing the clinical results and rotational stability between reconstructed anterior cruciate ligament (ACL) with intact ALL knees and reconstructed ACL with ALL injured knees.

Malignant clear-cell myomelanocytic tumor of broad ligament—a case report

Clear-cell myomelanocytic tumors (CCMT) of the perivascular epithelioid cell tumor (PEComa) family have been recently reported. We report a case involving a 12-year-old girl. The tumor (9 × 7.5 × 7 cm) was a firm, tan–gray mass with heavily dark pigmentation, massive hemorrhage, and necrosis, and was located in the right broad ligament attached to the right ovary. Histologically, the tumor was composed of polygonal cells exhibiting diffuse hemorrhage, multifocal necroses, and vascular invasion. Most of the tumor cells contained melanin pigments with Fontana–Masson positivity and ultrastructurally suspicious, membrane-bound premelanosomes. Immunohistochemical staining was positive against HMB-45 and focally positive for smooth muscle actin. The tumor recurred in the form of multiple conglomerated masses of the right iliac fossa, with the greatest measuring up to 3.8 cm in dimension, within 1 year. Most CCMT are believed to originate from falciform ligament/ligamentum teres. To the best of our knowledge, this is the second report of a CCMT arising in the broad ligament with typical morphology and contributory ancillary results. Further study for proper subclassification of the PEComa family should be validated, not by anatomic site but by clinical behavior.     

A novel silk-based artificial ligament and tricalcium phosphate/polyether ether ketone anchor for anterior cruciate ligament reconstruction – Safety and efficacy in a porcine model

Loss of ligament graft tension in early postoperative stages following anterior cruciate ligament (ACL) reconstruction can come from a variety of factors, with slow graft integration to bone being widely viewed as a chief culprit. Toward an off-the-shelf ACL graft that can rapidly integrate to host tissue, we have developed a silk-based ACL graft combined with a tricalcium phosphate (TCP)/polyether ether ketone anchor. In the present study we tested the safety and efficacy of this concept in a porcine model, with postoperative assessments at 3 months (n = 10) and 6 months (n = 4). Biomechanical tests were performed after euthanization, with ultimate tensile strengths at 3 months of ∼370 N and at 6 months of ∼566 N – comparable to autograft and allograft performance in this animal model. Comprehensive histological observations revealed that TCP substantially enhanced silk graft to bone attachment. Interdigitation of soft and hard tissues was observed, with regenerated fibrocartilage characterizing a transitional zone from silk graft to bone that was similar to native ligament bone attachments. We conclude that both initial stability and robust long-term biological attachment were consistently achieved using the tested construct, supporting a large potential for silk–TCP combinations in the repair of the torn ACL.     

TNF-α induced down-regulation of lysyl oxidase family in anterior cruciate ligament and medial collateral ligament fibroblasts

BackgroundThe lysyl oxidase (LOX) family has the capacity to catalyze the cross-linking of collagen and elastin, implicating its important fundamental role in injury healing. Tumor necrosis factor alpha (TNF-α) is considered to be an important chemical mediator in the acute inflammatory phase of the ligament injury. The role of the lysyl oxidase family induced by TNF-α in the knee ligaments' wound healing process is poorly understood. Our purpose was to determine the different expressions of the LOXs in poorly self-healing anterior cruciate ligament (ACL) and well functionally self-healing medial collateral ligament (MCL) induced by TNF-α.MethodsSemi-quantitative PCR, quantitative real-time PCR and western blot were performed for original research.ResultsThe results showed that all LOX family members were expressed at higher levels in MCL than those in ACL fibroblasts; the significant differences existed in the down-regulations of the LOXs induced by TNF-α; and the TNF-α-mediated down-regulations of the LOXs were more prominent in ACL than those in MCL fibroblasts. 1–20 ng/ml TNF-α down-regulated mRNA levels in ACL and MCL fibroblasts by up to 76% and 58% in LOX; 90% and 45% in LOXL-1; 97.5% and 90% in LOXL-2; 89% and 68% in LOXL-3; 52% and 25% in LOXL-4, respectively. Protein assay also showed LOXs had lower expressions in ACL than those in MCL.ConclusionsBased on these results, the differential expressions of the LOXs might help to explain the intrinsic differences between the poorly self-healing ACL and well functionally self-healing MCL.Clinical relevance.     

Does the cardinal ligament of the uterus contain a nerve that should be preserved in radical hysterectomy?

The cardinal ligament (CL) of the uterus is present as a specific part of the parametrium when the pararectal and paravesical spaces are developed surgically. According to usual nerve-sparing radical hysterectomy (the Tokyo method), the CL is divided into two parts, the vascular part for dissection and the nerve part that contains the pelvic splanchnic nerve (PSN) as a major target for nerve sparing. In contrast, we hypothesized that the CL and another structure outside of the usual area for surgical dissection, that is, the lateral rectal ligament, are mutually continuous and that the PSN runs through the lateral ligament rather than the CL. In the present study, a combination of routine dissection, fresh cadaver dissection and in situ sectional anatomy revealed that: (i) the CL did not contain the PSN; (ii) a well-defined fascial structure existed in the bottom or dorsal margin of the CL area; and (iii) the pelvic plexus was separated from vascular components of the CL. The present results provide a new perspective for nerve-sparing radical hysterectomy with extensive lateral parametrial dissection of the CL.     

Transverse humeral ligament: Does it exist?

The insertion of the tendon of subscapularis is accepted as being on the lesser tubercle of the humerus. The transverse humeral ligament (THL) is described as a distinct entity in most textbooks, overlying the long tendon of biceps as it emerges from the capsule of the shoulder joint. In this study, we dissected 85 embalmed shoulders to clarify the anatomy of the THL and variation in the insertion of the tendon of subscapularis. In all specimens no distinct THL could be identified, but in every shoulder a fibrous expansion arose from the posterior lamina of the tendon of pectoralis major overlying the long tendon of biceps. In 86% of shoulders, fibres from the tendon of subscapularis passed over the long tendon of biceps within this fibrous expansion and inserted on to the greater tubercle of the humerus where one would expect to find the THL. In 33% of dissections, fibres from the tendon of subscapularis lay deep to the long tendon of biceps, inserting either into the bicipital groove or on to the greater tubercle. In only 8% of cases did the tendon of subscapularis insert exclusively on to the lesser tubercle. We conclude that the THL does not exist as a separate entity. We suggest that in the majority of cases, the structure overlying the long tendon of biceps as it emerges from the capsule of the shoulder joint consists of tendinous fibres from subscapularis, contained within a fibrous expansion derived from the posterior lamina of the tendon of pectoralis major. In the minority of shoulders, where the tendon of subscapularis inserts exclusively on to the lesser tubercle, we hypothesise that this fibrous expansion acts as a retinaculum preventing the long tendon of biceps from "bowstringing."     

Extension deficit after anterior cruciate ligament reconstruction: Is arthroscopic posterior release a safe and effective procedure?

Background

Postoperative extension deficits following anterior cruciate ligament (ACL) reconstruction can cause major limitation during daily life. The purpose of this study was to evaluate the efficiency of an all-arthroscopic approach and posterior capsule release for the treatment of persistent knee extension deficits following ACL reconstruction.

Posterior cruciate ligament reconstruction implemented by the Ligament Advanced Reinforcement System over a minimum follow-up of 10 years

PurposeThis study evaluated the long-term clinical follow-up results of patients who underwent double-bundle posterior cruciate ligament (PCL) reconstruction using the Ligament Advanced Reinforcement System (LARS).MethodsPatients were assessed using clinical scores that included the Tegner activity level scale, the Lysholm score, and the International Knee Documentation Committee (IKDC) score. KT-1000 was adopted to assess stability. Radiographs and magnetic resonance imaging (MRI) were used to evaluate osteoarthritis and LARS condition.ResultsThis study examined 38 patients, of which follow-up procedures were completed for 33 patients, resulting in a follow-up rate of 86.8%. The average follow-up period was 11.9 ± 1.2 years (range: 10.3–14.2 years). The median scores of the clinical scales were as follows: Tegner activity score, 6 (range: five to seven); Lysholm score, 90 (range: 67–100); and IKDC score, 89.7 (range: 46–100). The median of the side-to-side difference (SSD) was four millimeters (range: 0–10 mm). In radiographs, the moderate OA rate was 6.9%. MRI results revealed that 26 patients exhibited ingrowth and 11 patients exhibited partial rupture of the LARS. With SSD ≤ 3 mm set as the standard for successful knee stabilization, the optimal cutoff point of LARS midsubstance thickness in the receiver operating characteristic (ROC) curve analysis was 14.3 mm.ConclusionsLong-term follow-up of the studied patients demonstrated the durability of LARS. However, clinical outcomes showed no enhancement using LARS, so it is not recommended for routine use in PCL reconstruction.Level of evidenceIV.     

Anterior cruciate ligament fixation: Is radial force a predictor of the pullout strength of soft-tissue interference devices?

BackgroundIn anterior cruciate ligament (ACL) reconstruction, an interference device achieves soft-tissue graft fixation by radially compressing the graft against the bone.PurposeThe objective of this study was to measure the radial force generated by different interference devices and evaluate the effect of this radial force on the pullout strength of graft-device constructs.Study DesignControlled laboratory study.MethodsA resultant force (F_R) was used as a representative measure of the total radial force generated. Bovine tendons were fixated in either synthetic bone or porcine tibia using one of following devices: (1) RCI titanium screw, (2) PEEK screw, (3) IntraFix sheath-and-screw device, and (4) ExoShape sheath-and-insert device. F_R was measured while each device was inserted into synthetic bone mounted on a test machine (n = 5 for each device). In a subsequent test series, graft-device constructs were loaded to failure at 50 mm/min. The pullout strength was measured as the ultimate load before failure (n = 10 for each device).ResultsThe F_R values generated during insertion into synthetic bone were 777 ± 86 N, 865 ± 140 N, 1313 ±198 N, and 1780 ± 255 N for the RCI screw, PEEK screw, IntraFix, and ExoShape, respectively. The pullout strengths in synthetic bone for the RCI screw, PEEK screw, IntraFix and ExoShape were 883 ± 125 N, 716 ± 249 N, 1147 ± 142 N, and 1233 ± 190 N, respectively.ConclusionsThese results suggest that the F_R generated during interference fixation affects the pullout strength with sheath-based devices providing superior F_R compared with interference screws. The use of synthetic bone was validated by comparing the pullout strengths to those when tested in porcine tibia.Clinical relevanceThese results could be valuable to a surgeon when determining the best fixation device to use in the clinical setting.     

How does wrist position affect the length of the distal radioulnar ligament: a three-dimensional image study in vivo?

Purpose

This study was designed to investigate the length changes of the distal radioulnar ligament at different wrist positions and to determine the effect of hyperextension on the distal radioulnar ligament and to find out the most vulnerable position where the distal radioulnar ligament rupture and foveal avulsion.

Methods

We obtained computed tomography scans of the wrists for 12 volunteers including two groups: hyperextension group and hyperextension with maximal rotation group. The images were reconstructed to the three-dimensional bone structures with customized software. The four portions of the distal radioulnar ligament were measured and analyzed statistically.

Results

No significant differences were noted in the lengths of the each portion of the distal radioulnar ligament among neutral position, wrist hyperextension, and hyper-radial extension. From neutral position to hyperextension with maximal pronation, the lengths of the palmar superficial radioulnar ligament (psRU) and dorsal deep radioulnar ligament (ddRU) decreased significantly, whereas the dorsal superficial radioulnar ligaments (dsRU) and palmar deep radioulnar ligament (pdRU) increased significantly. From neutral position to hyperextension with maximal supination, the lengths of the pdRU and dsRU ligaments decreased significantly, and the lengths of psRU and ddRU ligaments changed little.

Conclusions

The factor of hyperextension has little effect on the length of the distal radioulnar ligament and the distal radioulnar ligament may be under great tension at the position of hyperextension with maximal pronation. These findings can provide more information to understand the pathomechanics of the triangular fibrocartilage complex injury caused by a fall on the outstretched hand and can provide information relevant to the distal radioulnar ligament restoration.

     

Does the anterolateral ligament protect the anterior cruciate ligament in the most common injury mechanisms? A human knee model study

BackgroundAnterior cruciate ligament (ACL) reconstruction still has a risk of re-rupture and persisting rotational instability. Thus, extra-articular structures such as the anterolateral ligament (ALL) are increasingly treated. The ALL however prevents the internal rotation of the tibia and it must be doubted that the ALL protects the ACL in other common injury mechanisms which primarily include tibial external rotation. In this study we aimed to evaluate which extra-articular structures support the ACL in excessive tibial internal and external rotation using a knee finite element (FE) model.MethodsInternal and external rotations of the tibia were applied to an FE model with anatomical ACL, posterior cruciate ligament (PCL), lateral collateral ligament (LCL), medial collateral ligament (MCL) and intact medial and lateral meniscus. Three additional anatomic structures (anterolateral ligament, popliteal tendon and posterior oblique ligament) were added to the FE model separately and then all together. The force histories within all structures were measured and determined for each case.ResultsThe ACL was the most loaded ligament both in tibial internal and external rotation. The ALL was the main stabilizer of the tibial internal rotation (46%) and prevented the tibial external rotation by only 3%. High forces were only observed in the LCL with tibial external rotation. The ALL reduced the load on the ACL in tibial internal rotation by 21%, in tibial external rotation only by 2%. The POL reduced the load on the ACL by 8%, the PLT by 6% in tibial internal rotation. In tibial external rotation the POL and PLT did not reduce the load on the ACL by more than 1%.ConclusionThe ALL protects the ACL in injury mechanisms with tibial internal rotation but not in mechanisms with tibial external rotation. In injury mechanisms with tibial external rotation other structures that support the ACL need to be considered.     

In vivo structural and cellular remodeling of engineered bone–ligament–bone constructs used for anterior cruciate ligament reconstruction in sheep

ABSTRACT

Anterior cruciate ligament (ACL) ruptures rank among the most prevalent and costly sports-related injuries. Current tendon grafts used for ACL reconstruction are limited by suboptimal biomechanical properties. We have addressed these issues by engineering multiphasic bone–ligament–bone (BLB) constructs that develop structural and mechanical properties similar to native ACL. The purpose of this study was to examine the acute remodeling process that occurs as the BLB grafts advance toward the adult ligament phenotype in vivo. Thus, we implanted BLB constructs fabricated from male cells into female host sheep and allowed 3, 7, 14, or 28 days (n = 4 at each time point) for recovery. To address whether or not graft-derived cells were even necessary, a subset of BLB constructs (n = 3) were acellularized, implanted, and allowed 28 days for recovery. At each recovery time point, the following histological analyses were performed: picrosirius red staining to assess collagen alignment and immunohistochemistry to assess both graft development and host immune response. Polymerase chain reaction (PCR) analysis, performed on every explanted BLB, was used to detect the presence of graft-derived male cells remaining in the constructs and/or migration into surrounding host tissue. The analysis of the PCR and histology samples revealed a rapid migration of host-derived macrophages and neutrophils into the graft at 3 days, followed by increased collagen density and alignment, vascularization, innervation, and near complete repopulation of the graft with host cells within 28 days. This study provides a greater understanding of the processes of ligament regeneration in our BLB constructs as they remodel toward the adult ligament phenotype.     

Income change after cruciate ligament injury — A population-based study

ObjectivesTo investigate the association between choice of treatment and patients' income after cruciate ligament (CL) injury and assess the effect of different covariates such as sex, age, comorbidities and type of work.MethodsThis entire-population cohort study in Sweden included working patients with a diagnosed CL injury between 2002 and 2005, identified in The National Swedish Patient Register (n = 13,662). The exposure was the treatment choice (operative or non-operative treatment). The main outcome measure was average yearly income five years after CL diagnosis, adjusted for the following covariates: sex, age, comorbidities, type of work, region, calendar year, education and income.ResultsRelative to non-operative treatment, operative treatment was associated with greater average yearly incomes (nine to 15%) after injury among patients between 20 and 50 years, patients with partial university education, patients living in large cities and patients with one comorbidity, despite no overall significant association in the national cohort. Delayed operative treatment (> 1 year) had no significant association with income change, whereas early operative treatment (< 1 year) was associated with higher average yearly incomes (11 to 16%) among females, patients between 20 and 50 years, patients living in large cities and patients with one comorbidity.ConclusionsIn a broad sense, treatment choice was not associated with changes in income five years after CL injuries among patients in the workforce, however earlier operative treatment was associated with higher average incomes among patients with ages between 20 and 50, females, living in large cities, with one comorbidity and with a high level of education.     

Retain or sacrifice the posterior cruciate ligament in total knee arthroplasty? A histopathological study of the cruciate ligament in osteoarthritic and rheumatoid disease

BACKGROUND: The decision whether to retain or resect the posterior cruciate ligament in total knee arthroplasty is at present determined clinically by preoperative radiological variables focusing upon the amount of joint destruction, and subsequent soft tissue contractures. However, these variables give only indirect information on the histological integrity and proprioceptive properties of the posterior cruciate ligament. METHODS: Twenty posterior cruciate ligaments, obtained during total knee arthroplasty, were evaluated histologically to study the relation between the degree of preoperative radiological joint destruction, structural integrity of the posterior cruciate ligament and the neurological integrity of the targeted tissue. Eleven patients had osteoarthritis and nine patients rheumatoid arthritis. Haematoxylin and eosin, Alcian blue (mucoid degeneration), elastica von Gieson, Gomori (elastic fibres and collagen), and immunohistochemical staining for neural structures were used. RESULTS: In all but one of the posterior cruciate ligaments, morphologically intact neural tissue was present in the peritendineum of the ligaments. Structural integrity of the collagen framework was present in only seven posterior cruciate ligaments. These cases all had grade three or four radiological joint destruction. In 13 of the specimens a certain degree of mucoid degeneration of collagen was present. All patients with grade five radiological knee joint destruction displayed mucoid degeneration and irregularity of the posterior cruciate ligament fibres. CONCLUSION: Because of the extensive architectural and probably functional damage of the posterior cruciate ligament in patients who have grade five radiological knee joint destruction, retention of the posterior cruciate ligament in knee prosthesis should not be advocated.     

Is the posterior cruciate ligament destabilized after the tibial cut in a cruciate retaining total knee replacement?: An anatomical study

Introduction/purposeCruciate retaining total knee replacement has been shown to effectively improve pain and quality of life. Successful outcomes depend on many factors, including the maintenance of a competent posterior cruciate ligament. This study sought to anatomically analyze the percentage of PCL injured during a full transverse, tibial cut, thus altering normal function.Materials and methodsOne hundred and thirty five consecutive knee MRIs taken from 2006 to 2011 were selected from a single surgeon's database for this study. Only subjects with non-arthritic knees were considered for this study; the lack of degenerative joint disease (DJD) was confirmed via a radiological report. The optimal view of the PCL's tibial attachment was observed using the sagittal view of the knee, with a T1 signal. One hundred and twenty two usable images were viewed electronically, and measurements were made using the standardized transverse cut implant guidelines. The percentage of PCL remaining following the cut was categorized into five different groups: 0% (no PCL undermined), 1–49%, 50–74%, 75–99% and 100% (PCL undermined entirely).ResultsOverall only 9.0% (n = 11) would have not endured any damage to the PCL with a transverse tibial saw cut, while 79.6% (n = 98) would have had 50% or more of the PCL undermined. Of the 98 patients with more than 50% resected, 52.1% (n = 51 patients) presented complete destabilization of the PCL. The percentage of PCL destabilized was not significant across age groups (p = 0.280), gender (p = 0.586), or operative side (p = 0.460).ConclusionIndependent of age, gender, and operative side, a majority of PCLs are more than 50% destabilized following the standard transverse tibial cut.Level of evidenceII     

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

BackgroundFew 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.MethodsProspective 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.ResultsSeventy-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.ConclusionAt 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 evidenceLevel IV; case series.     

Is contralateral autogenous patellar tendon graft a better choice than ipsilateral for anterior cruciate ligament reconstruction in young sportsmen? A randomized controlled trial

AimThe aim of this study was to compare the peak extensor torque (primary outcome), sensory-motor capacity and Lysholm questionnaire score up to the fourth postoperative month post-primary anterior cruciate ligament reconstruction (ACLR) with bone–patellar-tendon–bone (BPTB) graft using either ipsilateral or contralateral technique in young sportsmen.MethodsWe performed a randomized controlled trial from 2018 to 2019. The same preoperative protocol, surgical technique and postoperative protocol were used in both groups. Eighty-eight young adult male patients were randomized, and 44 of each group completed the trial.ResultsAfter the follow up analysis, the contralateral receptor and donor limb demonstrated a statistically significant increase in peak extension torque compared with the ipsilateral operated limb (effect size (ES) = 0.99, power = 0.99, P < 0.0001; ES = 0.46, power = 0.56, P < 0.04). The symmetry between limbs was compared between groups. In the contralateral group, there was a significant decrease in the recipient limb (after surgery), compared with the donor limb (before surgery) (ES = 0.87, power = 0.99, P < 0.0001). In the ipsilateral group, the operated limb demonstrated a significant decrease in peak extension torque compared with the non-operated limb after surgery (ES = 1.88, power = 0.99, P < 0.0001). The comparison between groups in sensory-motor capacity and Lysholm score demonstrated a non-significant group effect postoperatively.ConclusionThe use of contralateral BPTB is more effective in increasing peak extension torque when compared with ipsilateral technique in young sportsmen. Furthermore, patients achieved greater symmetry (side to side) in quadriceps muscle performance after the 4-month follow up with a contralateral graft.     

The anterior cruciate ligament–lateral meniscus complex: A histological study

The anterior root of the lateral meniscus (LM) dives underneath the tibial attachment of the anterior cruciate ligament (ACL). Although the distinct role of meniscal attachments has been investigated, the relationship between the LM anterior insertion (LMAI) and ACL tibial insertion (ACLTI) remains unclear. This study histologically analyzed the LMAI and ACLTI. Samples were divided into four regions in an anterior-to-posterior direction. Histological measurements of these insertion sites were performed using safranin O-stained coronal sections. Distribution and signal densities of type I and II collagen were quantified. The ACLTI and LMAI formed the ACL–LM complex via fiber connections. The anterior part of the ACLTI had a widespread attachment composed of dense fibers. Attachment fibers of the LMAI became dense and wide gradually at the middle-to-posterior region. The ACL–LM transition zone (ALTZ) was observed between the LMAI and the lateral border of the ACLTI at the middle part of the ACL tibial footprint. Type II collagen density of the LMAI was higher than that of the ACLTI and ALTZ. Our results can help create an accurate tibial bone tunnel within the dense ACL attachment during ACL reconstruction surgery.