ACL anatomy: Is there still something to learn?

BACKGROUND

The different bony and soft tissue reference points and the micro and macroscopic structures of the knee continue to be the object of focused study and analysis. Upon reviewing the most recent literature, we saw the wide spectrum of studies that seek to define the different anatomical aspects of the anterior cruciate ligament (ACL).

PURPOSE

The purpose of this paper is to review the most recent publications on the ACL and its morphology in which its microscopic composition and macroscopic anatomy are addressed.

RESULTS

The ACL consists of typeI (90%) and typeIII (10%) collagen matrix. Its length ranges from 27 to 38mm and its width from 10 to 12mm. The ACL cross-section area measures an average of 44mm2, and its shape resembles that of an hourglass or a bow tie. ACL bundles have been defined as anteromedial, intermediate, and posterolateral. Femoral and tibial footprints were seen to present a high degree of variability in shape and size. Furthermore, the blood supply is given by the medial genicular artery and innervation by the tibial nerve branches. Additionally, the ACL functionally prevents anterior translation of the tibia and stabilizes against the internal rotation of the tibia and valgus angulation of the knee.

CONCLUSIONS

There is great variability in the anatomy of the ACL as well as its attachment sites. At the same time, the shape and size of its footprint has become a factor in determining individualized ACL reconstruction. The persistence of morphological variability in the aging of the ACL and important aspects of surgical planning and decision making with respect to anatomical risk factors suggest that further studies are called for.

Epidural administration of ropivacaine and midazolam is superior to intra-articular administration as postoperative analgesia after isolated arthroscopic anterior cruciate ligament reconstruction with hamstrings autograft: a randomized controlled clinical trial

OBJECTIVE

Reconstructive surgery of the anterior cruciate ligament (ACL) is quite common, previous studies have documented that adequate pain control in the early phases of the postoperative period translates into early mobility and a rapid start of rehabilitation. Therefore, the search for new strategies for postoperative pain control is justified. The aim of this study was to compare intra-articular to the epidural administration of ropivacaine and midazolam as postoperative analgesia after arthroscopic ACL reconstruction with hamstring autograft (HA).

MATERIAL AND METHODS

Double-blinded, prospective randomized clinical trial included 108 consecutive patients aged from 18 to 50 years that had undergone arthroscopic ACL reconstruction with HA. The patients were randomly assigned to 2 groups. The first group received intraarticular ropivacaine and midazolam. The second group received epidural ropivacaine and midazolam. The need for rescue analgesia, the postoperative pain experienced, side effects and complications of the analgesic drugs were evaluated.

RESULTS

The intra-articular group received statistically significantly higher mean doses of rescue analgesia on the first two days (2.8 ​± ​1.0 vs. 1.3 ​± ​0.6 in the epidural group; p ​= ​0.001). Visual Analogue Scale scores at flexion were statistically significantly higher in the intra-articular group over the entire study period. The intra-articular group also reported a statistically significantly lower range-of-motion 87 ​± ​15 vs. 102 ​± ​11 in the epidural group (p ​= ​0.001).

CONCLUSIONS

Epidural administration of ropivacaine combined with midazolam in patients undergoing primary ACL reconstruction with HA was clinically and significantly better relative to rescue analgesia and the intensity of pain in the first 48 postoperative hours when compared to intraarticular administration. There was no difference in terms of adverse effects and complications.

LEVEL OF EVIDENCE: 2

Mid-Term Clinical and Radiological Outcomes of Lateral Meniscal Allograft Transplantation with Suture-Only Fixation Plus Capsulodesis

Meniscal allograft transplantation (MAT) is an effective reconstructive procedure for treating a symptomatic postmeniscectomy syndrome. It consists of replacing the lost meniscal tissue aiming to improve the clinical outcomes and prevent progressive deterioration of the joint. The aim of this study was to evaluate meniscal graft survivorship and report on the radiographic (in terms of graft extrusion and joint space width and alignment) and the functional results through a midterm follow-up of lateral MAT performed with a soft tissue fixation technique after capsulodesis. In total, 23 patients who underwent lateral MAT as a single procedure were included. The Knee injury and Osteoarthritis Outcome Score, Lysholm, Tegner, and visual analog scale scales were used for patient assessment. Magnetic resonance imaging and a complete radiographic protocol were conducted to determine the degree of meniscal extrusion and the changes in the degree of osteoarthritis and coronal alignment. Assessments were performed after 2 and 7 years of follow-up. A significant improvement in all the scores, relative to preoperative values, was found after 7 years of follow-up. This improvement remained consistent throughout the first and second follow-up periods. A mean absolute extrusion of 2.2 mm ± 1.6 and an extrusion percentage of 28.0% ± 11.43 were found, with no significant differences throughout the follow-up periods. There was no statistically significant difference in terms of the frontal mechanical axis and joint space narrowing between the preoperative value and at the first and second follow-up periods. A survival rate of 85.7% was found after 7 years of follow-up. Capsulodesis results in a low degree of meniscal extrusion in isolated lateral MAT fixed with a suture-only technique, which is maintained after 7 years of follow-up, with a high graft survival index (>85%) and satisfactory results on the functional scales.

Effect of Injury to the Lateral Meniscotibial Ligament and Meniscofibular Ligament on Meniscal Extrusion: Biomechanical Evaluation of the Capsulodesis and Centralization Techniques in a Porcine Knee Model

Background

Previous biomechanical studies of the meniscotibial ligament have determined that it contributes to meniscal stability. An injury to it can cause the meniscus to extrude, and reconstruction of that ligament significantly reduces extrusion.

Purpose

To assess the biomechanical effects of sectioning the lateral meniscotibial ligament (LMTL) and the meniscofibular ligament (MFL) with respect to the radial mobility of the lateral meniscus and to evaluate the biomechanical effects of the capsulodesis and centralization techniques.

Study Design

Controlled laboratory study.

Methods

The lateral meniscus of 22 porcine knees was evaluated. They were mounted on a testing apparatus to apply muscle and ground-reaction forces. The meniscus was evaluated at 30° and 60° of knee flexion using 2 markers placed on the posterior cruciate ligament and the lateral meniscus after applying an axial compression of 200 N to the knee joint. Measurements were recorded under 5 conditions: intact lateral meniscus, injury of the LMTL, subsequent injury of the MFL, the use of the open capsulodesis technique, and the reconstruction of the LMTL and the MFL with the centralization technique.

Results

The distance between the 2 markers was significantly greater in the extrusion group (combined lesion of the LMTL and MFL) than in the intact or reconstruction groups (capsulodesis and centralization techniques; P < .001 in all cases). In the cases of load application, no significant differences were observed between the control group (intact meniscus) and the groups on which the reconstruction techniques were performed. There were also no differences when comparing the results obtained between both reconstruction techniques. In all settings, the distance between the 2 markers increased with the increase in the knee flexion angle.

Conclusion

In a porcine model, the LMTL and the MFL participated as restrictors of the radial mobility of the lateral meniscus during loading. Their injury caused a significant increase in lateral meniscal extrusion, and the centralization and the capsulodesis procedures were able to reduce extrusion.

Clinical Relevance

This study demonstrates the capacity of the LMTL and the MFL to restrict the radial mobility of the lateral meniscus during loading and how it is affected when they are injured.

ACL anatomy: Is there still something to learn?

BACKGROUND

The different bony and soft tissue reference points and the micro and macroscopic structures of the knee continue to be the object of focused study and analysis. Upon reviewing the most recent literature, we saw the wide spectrum of studies that seek to define the different anatomical aspects of the anterior cruciate ligament (ACL).

PURPOSE

The purpose of this paper is to review the most recent publications on the ACL and its morphology in which its microscopic composition and macroscopic anatomy are addressed.

RESULTS

The ACL consists of type I (90%) and type III (10%) collagen matrix. Its length ranges from 27 to 38mm and its width from 10 to 12mm. The ACL cross-section area measures an average of 44mm2, and its shape resembles that of an hourglass or a bow tie. ACL bundles have been defined as anteromedial, intermediate, and posterolateral. Femoral and tibial footprints were seen to present a high degree of variability in shape and size. Furthermore, the blood supply is given by the medial genicular artery and innervation by the tibial nerve branches. Additionally, the ACL functionally prevents anterior translation of the tibia and stabilizes against the internal rotation of the tibia and valgus angulation of the knee.

CONCLUSIONS

There is great variability in the anatomy of the ACL as well as its attachment sites. At the same time, the shape and size of its footprint has become a factor in determining individualized ACL reconstruction. The persistence of morphological variability in the aging of the ACL and important aspects of surgical planning and decision making with respect to anatomical risk factors suggest that further studies are called for.

Good clinical outcomes can be expected after meniscal allograft transplantation at 15 years of follow-up

PURPOSE

The aim of this study was to evaluate graft survivorship and report the functional and radiographic results of Meniscal allograft transplantation (MAT) throughout a minimum 15-year follow-up period.

METHODS

Fifty-one patients that had undergone an isolated MAT procedure during the period studied were included. The results were assessed with the Lysholm and Tegner scores as well as the Visual Analog Scale. Magnetic resonance imaging and a complete radiographic series were carried out to determine the degree of meniscal extrusion and joint space narrowing. A comparison was made between the radiological findings of the last follow-up, the 5-year mid-term follow-up and those from the preoperative period.

RESULTS

Thirty-eight patients were available for the final follow-up. The mean follow-up was 17.4 years. There were 23 (60.5%) medial menisci and 15 lateral menisci (39.4%). Meniscal extrusion increased from the 29.7% ± 14.9 obtained at the 5-year follow-up to the 72.5% ± 22.5 seen at the end of the follow-up (p = 0.0001). The joint space distance was almost unchanged from the initial evaluation (3.3 ± 1.5 mm) to the 5-year follow-up measurement (3.1 ± 1.7 mm, n.s.). However, it did decrease at the last follow-up (1.9 ± 1.5 mm, p < 0.05). The functional outcomes improved from the preoperative period to the mid-term follow-up and later worsened at the final follow-up. The mean preoperative Lysholm score at the initial follow-up was 61.5 ± 9.6, 86.9 ± 10.9 for the 5-year evaluation and stood at 77.4 ± 11.5 (p = 0.0001) at the final follow-up. Regarding the Tegner score, those pre-operative scores were compared to the ones at the last follow-up (median: 3; range 0-6 vs. 5.5; 3-6, respectively; p = 0.0001). The VAS went down from 6.6 ± 1.7 at the initial evaluation to 2.5 ± 1.9 at the final follow-up (p = 0.0001). The joint-space width remained unchanged from the initial evaluation (3.35 ± 1.5 mm) up to the 5-year follow-up measurement (3.1 ± 1.7 mm, n.s.). However, this joint-space distance had decreased by the last evaluation in the long-term follow-up (1.9 ± 1.4 mm, p < 0.05). Five patients (13.1%) presented with a MAT failure at 5 years, which was followed by extirpation of the meniscal graft. At the final follow-up, a total of 16 patients (42.1%) presented with a failure. At that time, there were 4 more MAT removals and seven patients that required a total knee replacement. The mean time to failure of the meniscal graft was 206.2 months ± 13.4 (18.0 years).

CONCLUSIONS

Meniscal allograft transplantation produces good functional results at a minimum 15-year follow-up. However, degenerative arthritis in the affected compartment progressed during that period.

LEVEL OF EVIDENCE

III.

Open Inferior glenohumeral joint dislocation with complete range of motion recovery: Case Report and literature review

Luxatio erecta is an inferior glenohumeral dislocation. It is an uncommon pathology with a prevalence of 0.5% of all shoulder dislocations. An open luxatio erecta presentation is rarer. After an extensive literature search, we only could find three complete case reports. From these cases, 2 out of 3 developed complications such as infections and severely limited range of motion, especially in flexion and abduction. We report the case of a 39-year-old man with an open inferior glenohumeral joint dislocation with complete rotator cuff tear and fracture of the greater tuberosity secondary to a motor vehicle accident. He was treated with open reduction, glenohumeral capsulorrhaphy, and transosseous rotator cuff repair with good clinical outcome. In conclusion, an open inferior shoulder dislocation is rare, less than 0.1% of all dislocations, with a high incidence of nerve injury. We suggest prompt surgical treatment with immediate administration of antibiotic therapy, wound debridement, irrigation, open reduction, and repair of the rotator cuff as an adequate protocol and focused rehabilitation with early mobilization of the glenohumeral joint.

Fixed-bearing unicompartmental knee arthroplasty provides a lower failure rate than mobile-bearing unicompartimental knee arthroplasty when used after a failed high tibial osteotomy: a systematic review and meta-analysis

Despite the fact that the choice of bearing design has been thought to influence the functional outcomes and longevity of unicompartimental knee arthroplasty (UKA), there is a lack of clinical evidence supporting the decision-making process in patients who have undergone high tibial osteotomy (HTO). A systematic review of studies was carried out that reported the outcomes of fixed-bearing (FB) or mobile-bearing (MB) medial UKA in patients with a previous HTO. A random effect meta-analysis using a generalized linear mixed-effects model to calculate revision rates was done. Seven retrospective cohort studies were included for this study. Regarding the fixation method, 40 were the FB-UKA and 47 were MB-UKA. For both groups, the mean post-operative follow-up was 5.8 years. The survival rates were 92% for the FB-UKA with a mean follow-up of 10 years. For the MB-UKA, it ranged from 35.7 to 93%, with a mean follow-up of 4.2 years. For the FB, the time to revision was reported as 9.3 years, while 1.2, 2.5 and 2.91 years was reported for the MB. The results of the meta-analysis showed that the revision rate for the patients receiving a FB-UKA after failed HTO was 8%, compared to 17% in those who received an MB-UKA. The results of the review suggest that the use of the FB-UKA is associated with lower revision rates and a longer survival time than the MB-UKA and have similar functional ability scores.Level of evidence: III (systematic review of level-III studies).

Vertebral destruction in an 11-month-old child with spinal tuberculosis: a case report and review of literature

Background

The incidence of tuberculosis is increasing especially in endemic countries. Spinal tuberculosis represents nearly the 50% of reported cases of skeletal tuberculosis. This is the youngest case of spinal tubercular disease that has been reported. The objective of this report is to describe a spinal tuberculosis case in an infant in thoracic spine, in order to show the importance of early diagnosis in this population, to limit the progression of this highly destructive disease and reduce the severe sequelae that this disease is associated.

Case presentation

An 11-month-old infant previously healthy born in the northeast Mexico. Physical examination revealed a mass lesion in the dorsal region, fixed to deep planes, indurated. Neurological examination found Frankel C paraparesis showing muscle strength 2/5 on the Lovett scale in both lower extremities, anal reflex present, and preserved sensitivity.

In the magnetic resonance of the spine, hyperintensities in the vertebral bodies of D6-D9 were observed in the T2 with destruction of the D7 and D8 bodies. A thoracotomy was performed with total mass resection with corpectomy of vertebrae D7 and D8, medullary decompression, and placement of fibula allograft between vertebrae D6 and D9. In the histopathological sample, a chronic granulomatous inflammatory process associated with acid-fast bacilli was observed, in addition to presenting a positive result in quantitative real-time PCR GeneXpert MTB/RIF sensitive to rifampicin. Twelve months later, he presented 5/5 muscular strength, without alterations in sensitivity, in addition to presenting ambulation onset at 18 months of age.

Conclusion

The spinal tuberculosis is a disease that occurs in endemic countries. A prompt diagnosis is necessary to limit the progression of a highly destructive disease. In addition, the fact of presenting at an early age produces hard making decisions for the adequate treatment of the disease and reduces the adverse effects of these procedures.

MRI evaluation of the peripheral attachments of the lateral meniscal body: the menisco-tibio-popliteus-fibular complex

PURPOSE

To determine, identify and measure the structures of the menisco-tibio-popliteus-fibular complex (MTPFC) with magnetic resonance imaging (MRI) in knees without structural abnormalities or a history of knee surgery.

METHODS

One-hundred-and-five knees without prior injury or antecedent surgery were analyzed by means of MRI. The average age was 50.1 years ± 14.8. All the measurements were performed by three observers. The peripherical structures of the lateral meniscus body were identified to determine the location, size, and thickness of the entire MTPFC. The distance to other "key areas" in the lateral compartment was also studied and compared by gender and age.

RESULTS

The lateral meniscotibial ligament (LMTL) was found in 97.1% of the MRIs, the popliteofibular ligament (PFL) in 93.3%, the popliteomeniscal ligaments (PML) in 90.4% and the meniscofibular ligament (MFL) in 39%. The anteroposterior distance of the LMTL in an axial view was 20.7 mm ± 3.9, the anterior thickness of the LMTL was 1.1 mm ± 0.3, and the posterior thickness of the LMTL 1.2 mm ± 0.1 and the height in a coronal view was 10.8 mm ± 1.9. The length of the PFL in a coronal view was 8.7 mm ± 2.5, the thickness was 1.4 mm ± 0.4 and the width in an axial view was 7.8 mm ± 2.2.

CONCLUSIONS

The MTPFC has a constant morphological and anatomical pattern for three of its main ligaments and can be easily identified and measured in an MRI; the MFL has a lower prevalence, considering a structure difficult to identify by 1.5 T MRI.

The morphology of the femoral footprint of the anterior cruciate ligament changes with aging from a large semicircular shape to a small flat ribbon-like shape

PURPOSE

Compare the differences in the morphology of the ACL femoral footprint between the cadavers of the young and elderly in consideration of the degenerative physiological process that occurs with aging.

METHODS

The femoral footprint of the ACL was dissected in 81 knees of known gender and age (45 male/36 female). They were divided into four groups by age and gender, establishing 50 years as the cut-off point to divide patients by age. Three observers analyzed the femoral footprint dissections, and the shapes were described and classified. The area and morphometric characteristics of the femoral insertion of the ACL were determined and these were compared between genders and age groups.

RESULTS

The femoral footprint of the ACL from the cadavers of males younger than 50 years of age presented a semicircular morphology in 90% of the cases. In males aged more than 50 years, a ribbon-like morphology was found in 96% of the cases. In women less than 50 years old, the semicircular morphology was observed in 93.7% of the cases. In women aged over 50 years old, the ribbon-like morphology was found in 95% of the cases. A significant difference was observed between the prevalence rates of the morphologies, area size and measurements of the younger and older groups (p < 0.001 for both genders).

CONCLUSIONS

The femoral insertion of the ACL presents variations in its morphology, area and morphometric characteristics over time. It goes from a large semicircular shape that almost contacts the posterior articular cartilage to a smaller, flattened ribbon-like shape that moves away from the edge of the articular cartilage. It is bounded anteriorly by the lateral intercondylar ridge. These findings should be considered to avoid employing reconstruction techniques in which femoral tunnels with oval or rectangular shapes are used in patients under 50 years of age because they do not correspond to the morphology of the femoral insertion of the ACL in this age group.

Hospitalization rate and costs in acute lymphoblastic leukemia of childhood in a low-income group: Financial impact in Northeast Mexico

BACKGROUND

Acute lymphoblastic leukemia (ALL) is one of the main and most expensive and prolonged causes of hospitalization for childhood cancer. We describe the hospitalization rate and its costs for an open population with ALL in a low-middle income country.

PROCEDURE

We retrospectively analyzed 449 hospital admissions for 101 pediatric patients with ALL over 8 years. Clinical files and electronic databases were scrutinized to document causes, duration, readmission rate, costs, and outcome of each admission. Hospitalizations were divided into two categories: general pediatric ward and pediatric intensive care unit (PICU). Hospitalization rates and its costs per patient were estimated considering person-time at risk.

RESULTS

Patients had an admission rate of 2.09 hospitalizations per patient-year and median length of stay per admission was 5 days. Most admissions occurred during the first 2 years from diagnosis. Mean cost per day was 239 US dollars (USD) and mean cost per stay was 2,246 USD versus 1,016 and 19,004 USD (P = 0.001) in the PICU, respectively. Total hospitalization cost per patient per year (PPPY) was 5,991 USD for high-risk patients and 3,038 USD for standard-risk patients. Patients between ages 1 and 9 years had a PPPY cost of $4,057; while for children younger than 1 year or older than 9 years, it was 7,463 USD. The popular medical insurance program covered 70% of hospitalizations and 63% of its total cost; patients contributed 2%, with the hospital absorbing 35%.

CONCLUSIONS

Hospitalizations for children with ALL were less expensive than in high-income countries but had a significant cost to low-income families and to the healthcare system.

High frequency of primary refractory disease and low progression-free survival rate of Hodgkin's lymphoma: a decade of experience in a Latin American center

BACKGROUND

Reports dealing with clinical outcomes of classical Hodgkin's lymphoma in low- to middle-income countries are scarce and response to therapy is poorly documented. This report describes the characteristics and clinical outcomes of patients with classical Hodgkin's lymphoma from a single institution in Latin America.

METHOD

A retrospective study was conducted over ten years of patients with classical Hodgkin's lymphoma treated at a referral center. Progression-free and overall survival rates were estimated by Kaplan-Meier analysis. The univariate Cox regression model was used to estimate associations between important variables and clinical outcomes.

MAIN RESULTS

One hundred and twenty-eight patients were analyzed. The mean age was 28.5 years. The five-year progression-free and overall survival were 37.3% and 78.9%, respectively. Of the whole group, 55 (43%) were primary refractory cases. Only 39/83 (47%) patients with advanced disease vs. 34/45 (75.6%) in early stages (p-value=0.002) achieved complete remission. Those with advanced disease had a five-year overall survival of 68.7% vs. 91.8% for early disease (p-value=0.132). Thirty-one patients relapsed (24.2%) and 20 (64.5%) received a transplant. The hazard ratio for progression with bone marrow infiltration was 2.628 (p-value=0.037). For death, an International Prognostic Score ≥4 had a hazard ratio of 3.355 (p-value=0.050) in univariate analysis. Two-thirds of classical Hodgkin's lymphoma patients diagnosed at advanced stages had a low progression-free survival but an overall survival similar to high-income countries.

CONCLUSION

Patients diagnosed with classical Hodgkin's lymphoma in Northeastern Mexico had a significantly low progression-free survival rate and presented with advanced disease, underscoring the need for earlier diagnosis and improved contemporary therapeutic strategies in these mainly young productive-age Hodgkin's lymphoma patients.