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.

[Translated article] Risk factors for infection of tibial plateau fractures

INTRODUCTION

Tibial plateau fractures are injuries prone to postoperative infection, with its reported incidence being higher than that of other fractures, between 5% and 12%. The primary objectives of this study were to quantify the postoperative infection rate of internal fixation of tibial plateau fractures (TPFs) and to identify the risk factors for this.

MATERIAL AND METHODS

Retrospective cohort study including patients who underwent TPF osteosynthesis between 2015 and 2020, in the same center. The study population was divided into two groups, according to the presence or absence of postoperative infection. Demographic variables related to the fracture, surgical parameters, as well as the need for reoperation were collected. Finally, in the case of debridement, the number of positive cultures and the pathogen responsible for the infection were collected, as well as the treatment applied.

RESULTS

One hundred and twenty-four patients were included, with a total of 14 infections (global infection rate of 11.3%). Risk factors for developing infection were open fractures (p=.002), Schatzker V and VI type fractures (p=.002) and the use of external fixation (p<.001). Regarding the surgical variables, only the longest ischemia time (p=.032) was identified as a risk factor. Staphylococcus aureus was the most frequently identified microorganism (43%), followed by Enterobacter cloacae (35.7%).

CONCLUSION

The overall infection rate after osteosynthesis of tibial plateau fractures was 11.3%. Different factors are associated with a higher risk of infection, including diabetes mellitus, open fractures, the use of external fixation, a higher grade in the Schatzker classification or a longer intraoperative ischemia time.

Risk factors for infection of tibial plateau fractures

INTRODUCTION

Tibial plateau fractures are injuries prone to postoperative infection, with its reported incidence being higher than that of other fractures, between 5% and 12%. The primary objectives of this study were to quantify the postoperative infection rate of internal fixation of tibial plateau fractures (TPF) and to identify the risk factors for this.

MATERIAL AND METHODS

Retrospective cohort study including patients who underwent TPF osteosynthesis between 2015 and 2020, in the same center. The study population was divided into two groups, according to the presence or absence of postoperative infection. Demographic variables related to the fracture, surgical parameters, as well as the need for reoperation were collected. Finally, in the case of debridement, the number of positive cultures and the pathogen responsible for the infection were collected, as well as the treatment applied.

RESULTS

One hundred and twenty-four patients were included, with a total of 14 infections (global infection rate of 11.3%). Risk factors for developing infection were open fractures (P=.002), Schatzker V and VI type fractures (P=.002) and the use of external fixation (P<.001). Regarding the surgical variables, only the longest ischemia time (P=.032) was identified as a risk factor. S. aureus was the most frequently identified microorganism (43%), followed by E. cloacae (35.7%).

CONCLUSION

The overall infection rate after osteosynthesis of tibial plateau fractures was 11.3%. Different factors are associated with a higher risk of infection, including diabetes mellitus, open fractures, the use of external fixation, a higher grade in the Schatzker classification or a longer intraoperative ischemia time.

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.

AB0047 CARTILAGE DEGRADATION STATUS OF KNEE OSTEOARTHIRTIC PATIENTS CAN BE PREDICTED BY CHONDROCYTE GENE EXPRESSION ANALYSIS

Background

Osteoarthritis (OA) is the most common degenerative joint disease, but its pathogenesis is still poorly understood. OA is characterized by articular cartilage loss due to an imbalance in anabolic and catabolic gene expression of the chondrocyte, together with aberrant expression of transcription factors and inflammatory mediators.

Objectives

We aim to evaluate de genes implicated in the chondrocyte failure regarding the four issues assessed to evaluate cartilage integrity using Mankin score (MkS): surface integrity, cellularity, cell cloning and staining.

Methods

Knee OA (KOA) patients aged 60-75 undergoing a total knee replacement, were recruited. At surgery, tibial plateau and femur condyles were deposited in DMEM medium and sent to the laboratory within 4 hours of the extraction. Punches from areas located at low, medium and high load (1) were excised from each sample (approximately 11 areas per patient). For RNA analysis, punches were kept in RNAlater at -20ºC until analyzed. RNA extraction, cDNA synthesis and cDNA amplification of the selected genes were performed previous to gene expression quantifycation by OpenArray Assay with custom plates. ΔCt was analyzed by ExpressionSuite V1.3 using 6 housekeeping genes. For histology study, punchs were fixated in formalin and embedded in parafin. Sections of 4 µm were stained with hematoxilin eosin and Safranin O-Fast Green. Slices were scored using the modified MkS (2) by 3 independent observers. R (v3.3.2) analysis was used to explored the results with principal components analysis (PCA) and linear regression (LR).

Results

Surgical samples were obtained from a total of 27 patients and 219 different areas were analyzed. ΔCt of the 51 genes analyzed by PCA showed that 9 components were enough to represent >80% of variance of the model. The genes associated with each component are summarized in Table 1. LR shows that second and first component were significantly associated to all or most of the fields included in the MkS, respectively. In contrast, component 4, 5 and 9 were not associated with any field. Lower expression of genes represented in component 1 (mainly related with extracellular matrix content) are associated with higher MkS values. On the other hand, component 2 summarizes data of genes mainly related with factors regulating cell metabolism. In this case, higher expression of TNFαIP6, NGF, IGFBP1, CRLF1, TNFα, and lower expression of ACAN, COL11A2, COL2A1, COL10A1, SOX9 and TGFβ1, among others, are associated with increased MkS values.

Table 1.

Genes that most contribute (by order) to component 1 & 2 (due to space limitation). Data of LR analysis for each component and MkS item. Significant association marked in bold.

ComponentGenesMankin score item (β coefficient; p-value)Surface integrityCellularityCell cloningStaining1SERPINE2, COL8A2, OGN, COL5A, TIMP3, BMP6, CRLF1, TIMP2, WISP1, ST3GAL1, SERPINE1, TNFSF10, ASPN, NGF, CD44, TNFRSF11B, TGFA, ADAMTS5, COL15A1, LUM, TNFAIP6, PTGS2, BMP2-0.092; 0.006-0.025; 0.047-0.028; 0.078-0.043; 0.0152ACAN, GPC5, CFH, FGFR3, COL11A2, TGFB1, GREM1, TNFAIP6, NGF, SOX9, IGFBP1, MMP3, FGF2, CRLF1, TNFa, COL2A1, COL10A10.261; 2.54 10-70.050; 0.0100.066; 0.0050.072; 0.0073-0.174; 0.003-0.029; 0.191-0.076; 0.0060.004; 0.89840.068; 0.410-0.019; 0.543-0.055; 0.161-0.021; 0.6275-0.082; 0.3640.051; 0.1460.020; 0.644-0.052; 0.28360.050; 0.6050.023; 0.5480.111; 0.0170.062; 0.2287-0.120; 0.266-0.090; 0.0320.010; 0.839-0.113; 0.0528-0.134; 0.2740.006; 0.892-0.198; 0.001-0.131; 0.0479-0.220; 0.096-0.041; 0.425-0.101; 0.1100.020; 0.780

Conclusion

There is a correlation between the expression level of the studied genes and the MkS values, although the role played by each gene might be different according to the MkS issue evaluated. These results could be useful to describe biomarkers that identify burden of disease in KOA.

References

[1]Adouni M, Shirazi-Adl A. J Orthop Res. 2014 Jan;32(1):69-78.

[2]Moody HR, Heard BJ, et al. J Anat. 2012 Jul;221(1):47-54.

Acknowledgements

We acknowledge Berend Bremmen for his help in Mankin Score bibliography revision and image scoring.

Disclosure of Interests

None declared

POS0179 IMPLICATIONS OF BRAIN ACTIVITY IN THE TREATMENT DECISION OF KNEE OSTEOARTHRITIS

Background

Chronic pain related to knee osteoarthritis (KOA) is a common health problem and functional magnetic resonance imaging (fMRI) is a useful technique which can determine different brain activation (1).

Objectives

The main purpose of our study was to observe whether there is different risk to central sensitization and different brain activation in patients with KOA according to the treatment followed (conservative (CNV) Vs. total knee replacement (TKR))

Methods

Patients diagnosed of primary KOA following a CNV treatment or undergoing TKR were recruited. The two groups were matched by age, sex and BMI. Clinical central sensitization was considered if patients presented spread tenderness, evaluated with an algometer, in more than 1 site of the extended peripatellar map (2) (notice that pain at points 3, 7 and 8 were not counted) fMRI testing involved pressure painful stimulation to the articular interline and to a commonly sensitized site (tibial surface, point 10).To evaluate the associations between central sensitization and the risk to undergo a TKR; logistic regression was performed to estimate OR and 95% confidence intervals (95%CI). Models were adjusted by sex, age and BMI (R (R v.3.5.2).Whole-brain activation maps were compared between groups using Statistical Parametric Mapping software (SPM12 http://www.fil.ion.ucl.ac.uk/spm).

Results

Women have a significant higher risk to present central sensitization than men (OD 12,11 (95% CI 4,32-33,95) p-value:2,09*106), but no differences were observed between CNV and TKR group (OR TKR 0,69 (95% CI 0,24-1,98)) (Table 1). The differences observed in brain activation between the treatment groups in the interline fMRI test (point 7) did not correspond to any specific brain area. However, TKR group showed a higher activation that implicated the region of the amygdala and anterior hippocampus during the tibial fMRI test (point 10).

Table 1.

Central sensitization Odds Ratio (OR) with 95% Confidence Interval (95%CI)

O.R. (95% CI)p-valueTreatment0.69 (0.24- 1.98)0,494Sex12.11 (4.32- 33.95)2,09*10-6Age0.72 (0.26- 1.97)0,525BMI1.88 (0.69- 5.17)0,219

Conclusion

Presenting central sensitization is not a risk for KOA patients to undergo a TKR, but the mechanism underlaying sensitization in both treatment groups might be different, with amygdala playing an important role in TKR patients. The amygdala is an important element of the brain systems that both express emotions and modulate pain. The activation of the amygdala in response to pressure stimulation on a sensitized knee site is interpreted as a failure of the descending pain inhibitory systems, and the occurrence of a major emotional response during the painful experience in patients that ultimately received TKR.

References

[1]Pujol, J. et al., 2017. Brain imaging of pain sensitization in patients with knee osteoarthritis. Pain, 158(9), pp.1831–1838.

[2]Arendt-Nielsen L, Nie H, Laursen MB, Laursen BS, Madeleine P, Simonsen OH, Graven-Nielsen T. Sensitization in patients with painful knee osteoarthritis. Pain 2010;149:573-8

Extended peripatellar map including the points tested for tenderness, and brain areas differently activated between both treatments groups during painful stimulation to point 7 (interline) and point 10 (tibial surface, a commonly sensitized site).

Disclosure of Interests

None declared

Anxiety is the cause of the worse outcomes of allergic patients after total knee arthroplasty

PURPOSE

The presence of allergies has been proposed as a risk factor for worse outcomes in total knee arthroplasty surgery. The aim of this study is to evaluate if the presence of some psychiatric disorders is more frequent in patients who report allergies and if they could be the main cause for the worse outcomes.

METHODS

A prospective study, including patients undergoing a primary total knee arthroplasty, was designed. In the preoperative visit, all the patients completed a questionnaire about the presence of allergies and also psychiatric tests for anxiety (State-Trait Anxiety Inventory-STAI-), depression (Remission from Depression Questionnaire-RDQ-), somatization disorder (Patient Health Questionnaire-15-PHQ-15-), pain catastrophizing syndrome (Pain Catastrophizing Scale-PCS), and personality disorder (Reduced NEO-Inventory of Five Factors-NEO-FFI-). In the preoperative and at 6 months of follow up, the functional results of the surgery were assessed by the WOMAC, the SF-12, and the KSS scores.

RESULTS

A total of 209 patients was included: 136 (65%) did not have reported allergies and 73 (35%) did report some allergies. The psychiatric questionnaires showed that the presence of anxiety was more prevalent in the group of patients with reported allergies (STAI-T: no allergies 24.08 points vs. allergies 19.18 points, p = 0.039). When comparing the functional outcomes at 6 months of follow up, most of the analyzed scores improved less in the group of patients with reported allergies than in the no allergy-referred group: WOMAC-total score (34.37 vs. 40.10 points, p = 0.023), WOMAC-pain score (6.03 vs. 7.50 points, p = 0.018), WOMAC-function score (22.97 vs. 27.24 points, p = 0.023), KSS-knee score (25.37 vs. 33.79 points, p = 0.002), and SF-12 physical score (7.89 vs. 11.15 points, p = 0.046). The significance of the difference in the outcomes scores in this group was lost after adjusting for anxiety (p > 0.05).

CONCLUSION

Allergies reported by patients are confirmed as a risk factor for worse results after TKA surgery. The relationship with anxiety disorder seems to explain the association between self-reported allergies and sub-optimal outcomes.

LEVEL OF EVIDENCE

II.

FRI0426 EMOTIONAL COMPONENTS AND INFLAMMATION ARE HIGHLY RELEVANT IN PAIN REPORTED BY KNEE OSTEOARTHRITIC PATIENTS

Background:

Osteoarthritis (OA) is a leading cause of disability in elderly and the most frequent form is knee OA (KOA) (1). Pain is the principal symptom that leads patients to visit clinicians, and it is the main reason, together with functionality, for patients to undergo a total knee replacement (TKR) after apparently unsuccessful conservative (CNV) treatments (2). It is well-known that there is a poor correlation between the radiographic severity (based on Kellgren & Lawrence (KL) score) and the reported pain (3), so other variables may be responsible for the intensity of pain.

Objectives:

Identifying the leading causes of pain in each patient would improve the management of the disease. In this study we aim to investigate the role of emotional components, nociception process and inflammation in treatment decision, as a global measure of pain suffered by KOA patients, taking into account sex, age and BMI.

Methods:

KOA patients, carefully selected to be idiopathic, graded 2-3 in KL, were recruited at Hospital del Mar. The following variables were recorded: WOMAC, Hospital Anxiety and Depression Scale (HAD), Pain Catastrophizing Scale (PCS), tender points (TP) (measure with a pressure algometer at points defined in the Arendt-Nielsen extended peripatellar map), synovial hypertrophy (SH) and effusion (SE) (measure by ultrasounds), and PCR and ESR serum levels. Patients were classified according to 4 factors: treatment (CNV/TKR), sex, age (60-67/68-75) and BMI (<30/>30). All groups were balanced. Multivariate and correlations analysis were performed.

Results:

Eighty-seven patients have been recruited. Patients from the TKR group present significant higher WOMAC (p=0.000), PCS (p=0.002) and SE (p= 0.038) values than CNV ones, without interaction with the other factors, except for SE, that presents interaction with BMI (Fig. 1). Women reported significant upper WOMAC (p=0.001) and HAD rates (p=0.020), but also higher number of TP and ESR levels (p= 0.000 and 0.002, respectively). The level of sensitization was significantly higher in women than in men (p=0.000). Several significant correlations were found, mainly between WOMAC and emotional components, as well as between TP and WOMAC, PCS, and inflammation markers (Table 1).

Conclusion:

PCS is an emotional component that could explain in part the lack of correlation between joint status and patient’s symptomatology. Working out strategies for pain management could improve this PCS values and therefore reduce the need for TKR. Furthermore, this study also highlights the two mainly types of OA etiology: mechanical and inflammatory. It suggests that inflammation is mostly responsible for OA progression in patients with low BMI, and plays a strong role in women pathology. Finally, specific treatments targeting central pain sensitization could also improve the management of the pathology in women.

References:

[1]Guccione AA, Felson DT, Anderson JJ, Anthony JM, Zhang Y, Wilson PW, et al. The effects of specific medical conditions on the functional limitations of elders in the Framingham Study. Am J Public Health. 1994 Mar;84(3):351-8.

[2]O’Neill TW, Felson DT. Mechanisms of Osteoarthritis (OA) Pain. Curr Osteoporos Rep. 2018 Oct;16(5):611-6.

[3]Dieppe PA. Relationship between symptoms and structural change in osteoarthritis. what are the important targets for osteoarthritis therapy? J Rheumatol Suppl. 2004 Apr;70:50-3.

Acknowledgments:

MICINN Funds are acknowledged (HOLOA-DPI2016-80283-C2-1/2-R)

Disclosure of Interests:

None declared

AB0874 FUNCTIONALITY IN OSTEOARTHRITIC GAIT IS RELATED TO TREATMENT DECISION. A MULTIFACTORIAL ANALYSIS

Background:

Osteoarthritis (OA) is a degenerative disease with complex underling mechanisms1–3. The interactions among several factors make the study of the disease very complex and often lead to different treatment, i.e. surgical or conservative, decisions for subjects clinically and radiographically similar. Recent explorations performed at the body level pointed out that macro-factors, like overweight or gait, can influence the development of the disease4. The number of related factors is high, and they are very likely to interact with each other. However, the literature lacks randomized and balanced studies to verify such effects of multiple factors5.

Objectives:

The aim of this work was to develop a multifactorial analysis to explore whether and how gait functionality and dynamics can be related to treatment decision.

Methods:

A multifactorial analysis of gait dynamics in OA subjects was developed. 81 OA subjects, graded 2-3 in KL, were selected based on 4 clinical factors: Gender (male – female), Age (60-67 – 68-75), BMI (25–29.9 – 30+) and Treatment (total knee replacement (TKR) – conservative treatment). Gait analysis was performed using 8 cameras BTS Smart-DX 700, 1.5 Mpixels 250 fps and 2 force plates BTS P-6000 500 Hz sampling (BTS S.p.A., Milan, Italy). Helen Hayes marker protocol with medial markers was used for the study. Each volunteer was asked to perform a minimum of 5 valid gait sequences. Functionality and dynamics parameters were measured.

Functionality: Velocity of gait and the time needed to perform a gait cycle were computed.

Dynamics:The reaction forces and torques at the ankles, knees and hips were computed through inverse dynamic analyses.

Analysis of variance was performed for the four factors described among the functionality and dynamics parameters.

Results:

The multifactorial analysis showed that functionality values are more subjective to the studied factors than the dynamics ones.

Functionalityseems to be directly related to the clinical treatment. Patients who selected TKR needed more time to make a step, spent more time in double stand position and walked slower (p<0.002). Older subject also walked slower but this dependency seemed to variate with age (interaction between clinical treatment and age – p<0.02 – Figure 1).

Figure 1

Interaction between Clinical treatment and age.

Dynamics: Forces at the joints seemed to be affected by the gender and an interaction between age and BMI (p< p<0.005, p<0.02) but not by the kind of therapy. Differently, torques were statistically related to the clinical treatment (p<0.007). Age was also significant as was the interaction between age and BMI (both p<0.007).

Conclusion:

Reduced functionality seems to be related to the selection of therapy. In contrast to current paradigm, forces at the joints may have no role in the definition of the best therapy for OA subjects. Subjects requiring TKR do not present higher loads at the joints. However, torques seems to be related to the therapy selected. Instead of forces, kinematics and posture assessments might support rational definitions of the therapy and future multifactorial analysis should take them into consideration.

References:

[1]Ding M. et al.J Bone Joint Surg Br. 2003;85(6):906-912.

[2]Kamibayashi L. et al.Calcif Tissue Int. 1995;57:69-73.

[3]Li B, Aspden RM.J Bone Miner Res. 1997;12(4):641-651.

[4]Berenbaum F et al.Curr Opin Rheumatol. 2013;25(1):114-118.

[5]Ioannidis JPA.Soc Sci Med. 2018;210(April):53-56.

Acknowledgments:

MICINN Funds are acknowledged (HOLOA-DPI2016-80283-C2-1/2-R, RYC-2015-18888)

Disclosure of Interests:

None declared

[Precision of arthroscopic surgeons using ultrasound for the first time to measure tendon structures]

BACKGROUND

The precision of a group of arthroscopic surgeons using ultrasound for the first time was assessed when measuring shoulder and hip tendon structures.

METHODS

Twenty-two students and 3 professors participated in a one-day theoretical-practical course. Two measurement rounds were conducted, during which each student identified the greater and lesser axes and the cross-sectional area of the biceps tendon, the supraspinous depth, as well as the lesser and greater axes and the cross-sectional area of the iliac psoas. The mean of the two measurements made by each of the course professors was considered as the reference value.

RESULTS

When the 2 measurements made by each of the students of each of the structures were assessed, no significant correlation was found in any of the cases, with a p 0.05. With the exception of the cross-sectional area of the biceps, where there was a significant undersizing of the structure, in the remaining 7 measurements a marked trend to oversize the structures was seen in both the first and second measurements, with a high statistical significance (p 0.05).

CONCLUSIONS

Ultrasound is a useful method through which arthroscopic surgeons can identify structures. However, the marked trend to oversize structures compared to the reference values leads to think that the training courses and the daily practice are essential to improve the method.

Pressure algometry is a useful tool to quantify pain in the medial part of the knee: an intra- and inter-reliability study in healthy subjects

PURPOSE

Pain quantification is essential for diagnostic and pain monitoring purposes in disorders around the knee. Pressure algometry is a method described to determine pressure pain threshold (PPT) by applying controlled pressure to a given body point. The purpose of this study was to determine the reliability of this method when it was applied to the medial part of the proximal tibia metaphysis and to evaluate the PPT levels between genders.

METHODS

Fifty healthy (mean age; 46.9) volunteers were recruited, 25 men and 25 women. Pressure algometry was applied to a 1 cm(2)-probe area on the medial part of the knee by 2 raters. Intra- and interclass correlation (ICC) was obtained and differences between genders were evaluated. Bland-Altman plots were performed to evaluate the variability of the measures.

RESULTS

The mean values of PPT obtained by rater 1 and 2 were 497.5 Kpa and 489 Kpa respectively. The intrarater reliability values (95% IC) for rater 1 and 2 were 0.97 (0.95-0.98) and 0.84 (0.73-0.90) respectively. With regard to interrater reliability, the ICC (95% IC) for the first measurement was 0.92 (0.87-0.95) and 0.86 (0.78-0.92) for the second one. Women showed significant lower values of PPT than men. The Bland-Altmand plots showed excellent agreement.

CONCLUSIONS

Pressure algometry has excellent reliability when it is applied to the medial part of the proximal metaphysis of the tibia. Women have lower values of PTT than men. The high reliability of the PA in an individual volunteer makes it a more valuable tool for longitudinal assessment of a given patient than for comparison between them.

LEVEL OF EVIDENCE

Level III. Prospective study.

[High recurrence and good functional results after arthroscopic resection of pigmented villonodular synovitis]

INTRODUCTION

Pigmented villonodular synovitis (PVS) is a synovial proliferation disorder of uncertain aetiology, with some controversy as regards its proper treatment. The purpose of the study was to evaluate the functional outcome and recurrence rate in a series of patients diagnosed with both the diffuse and the localised type of PVS and treated by arthroscopic resection.

MATERIAL AND METHODS

Twenty-four patients diagnosed with PVS were retrospectively assessed. There were 11 cases with the diffuse type, and 13 cases with the localised type of PVS. They were followed-up for a median of 60 months (range, 34-204). They underwent arthroscopic synovectomy, and were functionally evaluated with IKDC, WOMET, and Kujala scores.

RESULTS

There was recurrence in 8 out of 13 (61.5%) cases with the diffuse type of PVS. Two of these patients were treated with radiation. One patient underwent surgical resection with an open procedure due to extra-articular involvement. The remaining 5 patients underwent a second arthroscopic resection, and no recurrence was subsequently observed. Cases with localised PVS did not recur after a single arthroscopic resection. IKDC, WOMET and Kujala scores improved by 30.6, 37.4 and 34.03 points, respectively.

DISCUSSION

Pigmented villonodular synovitis treated by arthroscopic resection showed good functional results at mid-term follow-up. A single arthroscopic resection was sufficient to treat the localised PVS, whereas the diffuse type of PVS required a second arthroscopic resection in most cases, due to its high rate of recurrence.

Topical and intravenous tranexamic acid reduce blood loss compared to routine hemostasis in total knee arthroplasty: a multicenter, randomized, controlled trial

INTRODUCTION

Tranexamic acid (TXA) is becoming widely used in orthopedic surgery to reduce blood loss and transfusion requirements, but consensus is lacking regarding the optimal route and dose of administration. The aim of this study was to compare the efficacy and safety of topical and intravenous routes of TXA with routine hemostasis in patients undergoing primary total knee arthroplasty (TKA).

MATERIALS AND METHODS

We performed a randomized, multicenter, parallel, open-label clinical trial in adult patients undergoing primary TKA. Patients were divided into three groups of 50 patients each: Group 1 received 1 g topical TXA, Group 2 received 2 g intravenous TXA, and Group 3 (control group) had routine hemostasis. The primary outcome was total blood loss. Secondary outcomes were hidden blood loss, blood collected in drains, transfusion rate, number of blood units transfused, adverse events, and mortality.

RESULTS

One hundred and fifty patients were included. Total blood loss was 1021.57 (481.09) mL in Group 1, 817.54 (324.82) mL in Group 2 and 1415.72 (595.11) mL in Group 3 (control group). Differences in total blood loss between the TXA groups and the control group were clinically and statistically significant (p < 0.001). In an exploratory analysis differences between the two TXA groups were not statistically significant (p = 0.073) Seventeen patients were transfused. Transfusion requirements were significantly higher in Group 3 (p = 0.005). No significant differences were found between groups regarding adverse events.

CONCLUSION

We found that 1 g of topical TXA and 2 g of intravenous TXA were both safe strategies and more effective than routine hemostasis to reduce blood loss and transfusion requirements after primary TKA.

LEVEL OF EVIDENCE

I.

Clinical results after ultrasound-guided intratissue percutaneous electrolysis (EPI®) and eccentric exercise in the treatment of patellar tendinopathy

PURPOSE

To investigate the outcome of ultrasound (US)-guided intratissue percutaneous electrolysis (EPI(®)) and eccentric exercise in the treatment of patellar tendinopathy during a long-term follow-up.

METHODS

Forty patients with patellar tendinopathy were prospectively evaluated over a 10-year follow-up period. Pain and function were evaluated before treatment, at 3 months and at 2, 5 and 10 years using the Victorian Institute of Sport Assessment-Patella (VISA-P) score, the Tegner score and Blazina's classification. According to VISA-P score at baseline, patients were also dichotomized into Group 1 (<50 points) and Group 2 (≥50 points). There were 21 patients in Group 1 and 19 in Group 2. Patient satisfaction was measured according to the Roles and Maudsley score.

RESULTS

The VISA-P score improved globally by 41.2 points (p < 0.01) after a mean 4.1 procedures. In Group 1, VISA-P score improved from 33.1 ± 13 to 78.9 ± 14.4 at 3-month and to 88.8 ± 10.1 at 10-year follow-up (p < 0.001). In Group 2, VISA-P score improved from 69.3 ± 10.5 to 84.9 ± 9 at 3-month and to 96.0 ± 4.3 at 10-year follow-up (p < 0.001). After 10 years, 91.2 % of the patients had a VISA-P score >80 points. The same level (80 % of patients) or the Tegner score at no more than one level lower (20 % of patients) was restored, and 97.5 % of the patients were satisfied with the procedure.

CONCLUSION

Treatment with the US-guided EPI(®) technique and eccentric exercises in patellar tendinopathy resulted in a great improvement in knee function and a rapid return to the previous level of activity after few sessions. The procedure has proved to be safe with no recurrences on a long-term basis.

LEVEL OF EVIDENCE

Therapeutic study, Level IV.

[The geometry of the keel determines the behaviour of the tibial tray against torsional forces in total knee replacement]

The keel design of the tibial tray is essential for the transmission of the majority of the forces to the peripheral bone structures, which have better mechanical proprieties, thus reducing the risk of loosening. The aim of the present study was to compare the behaviour of different tibial tray designs submitted to torsional forces. Four different tibial components were modelled. The 3-D reconstruction was made using the Mimics software. The solid elements were generated by SolidWorks. The finite elements study was done by Unigraphics. A torsional force of 6 Nm. applied to the lateral aspects of each tibial tray was simulated. The GENUTECH® tibial tray, with peripheral trabecular bone support, showed a lower displacement and less transmitted tensions under torsional forces. The results suggest that a tibial tray with more peripheral support behaves mechanically better than the other studied designs.

Efficacy and safety of fibrin glue and tranexamic acid to prevent postoperative blood loss in total knee arthroplasty: a randomized controlled clinical trial

BACKGROUND

Postoperative blood loss in patients after total knee arthroplasty may cause local and systemic complications and influence clinical outcome. The aim of this study was to assess whether fibrin glue or tranexamic acid reduced blood loss compared with routine hemostasis in patients undergoing total knee arthroplasty.

METHODS

A randomized, single-center, parallel, open clinical trial was performed in adult patients undergoing primary total knee arthroplasty. Patients were divided into four groups. Group 1 received fibrin glue manufactured by the Blood and Tissue Bank of Catalonia, Group 2 received Tissucol (fibrinogen and thrombin), Group 3 received intravenous tranexamic acid, and Group 4 (control) had no treatment other than routine hemostasis. The primary outcome was total blood loss collected in drains after surgery. Secondary outcomes were the calculated hidden blood loss, transfusion rate, preoperative and postoperative hemoglobin, number of blood units transfused, adverse events, and mortality.

RESULTS

One hundred and seventy-two patients were included. The mean total blood loss (and standard deviation) collected in drains was 553.9 ± 321.5 mL for Group 1, 567.8 ± 299.3 mL for Group 2, 244.1 ± 223.4 mL for Group 3, and 563.5 ± 269.7 mL for Group 4. In comparison with the control group, Group 3 had significantly lower total blood loss (p < 0.001), but it was not significantly lower in Groups 1 and 2. The overall rate of patients who had a blood transfusion was 21.1% (thirty-five of 166 patients analyzed per protocol). Two patients required transfusion in Group 3 compared with twelve patients in Group 4 (p = 0.015). No significant difference was observed between the two fibrin glue groups and the control group with regard to the need for transfusion. There was no difference between groups with regard to the percentage of adverse events.

CONCLUSIONS

Neither type of fibrin glue was more effective than routine hemostasis in reducing postoperative bleeding and transfusion requirements, and we no longer use them. However, this trial supports findings from previous studies showing that intravenous tranexamic acid can decrease postoperative blood loss.

Cell-free cartilage engineering approach using hyaluronic acid–polycaprolactone scaffolds: A study in vivo

Polycaprolactone scaffolds modified with cross-linked hyaluronic acid were prepared in order to establish whether a more hydrophilic and biomimetic microenvironment benefits the progenitor cells arriving from bone marrow in a cell-free tissue-engineering approach. The polycaprolactone and polycaprolactone/hyaluronic acid scaffolds were characterized in terms of morphology and water absorption capacity. The polycaprolactone and polycaprolactone/hyaluronic acid samples were implanted in a chondral defect in rabbits; bleeding of the subchondral bone was provoked to generate a spontaneous healing response. Repair at 1, 4, 12, and 24 weeks was assessed macroscopically using the International Cartilage Repair Society score and the Oswestry Arthroscopy Score and microscopically using immunohistological staining for collagen type I and type II, and for Ki-67. The presence of hyaluronic acid improves scaffold performance, which supports a good repair response without biomaterial pre-seeding.

Surgical treatment for early osteoarthritis. Part II: allografts and concurrent procedures

Young patients with early osteoarthritis (OA) represent a challenging population due to a combination of high functional demands and limited treatment options. Conservative measures such as injection and physical therapy can provide short-term pain relief but are only palliative in nature. Joint replacement, a successful procedure in the older population, is controversial in younger patients, who are less satisfied and experience higher failure rates. Therefore, while traditionally not indicated for the treatment of OA, cartilage repair has become a focus of increased interest due to its potential to provide pain relief and alter the progression of degenerative disease, with the hope of delaying or obviating the need for joint replacement. The field of cartilage repair is seeing the rapid development of new technologies that promise greater ease of application, less demanding rehabilitation and better outcomes. Concurrent procedures such as meniscal transplantation and osteotomy, however, remain of crucial importance to provide a normalized biomechanical environment for these new technologies.

LEVEL OF EVIDENCE

Systematic review, Level II.

A porous PCL scaffold promotes the human chondrocytes redifferentiation and hyaline-specific extracellular matrix protein synthesis

The redifferentiation, proliferation, and hyaline-specific extracellular matrix (ECM) protein synthesis of chondrocytes cultured in a polycaprolactone (PCL) scaffold were analyzed. Gene expression of the type II collagen and aggrecan was assessed by real-time PCR in cells from PCL scaffolds, monolayer, and pellet cultures. The proliferative activity was assessed using Ki-67 immunodetection, and the chondrocytic differentiation was evaluated using S-100 immunodetection. The synthesis and deposition into scaffold pores of type II collagen and glycosaminoglycan were analyzed by immunohistochemistry and Alcian blue staining, respectively. All parameters were assessed throughout 28 days of cultures maintained in either fetal bovine serum-containing medium (FCM) or Insulin-Transferrin-Selenium-containing medium (ICM). Expression of the type II collagen gene was lower in FCM cultures than in ICM cultures for all culture systems (p < 0.05). Moreover, PCL scaffolds cultured in ICM were able to induce collagen gene expression more efficiently than pellet and monolayer cultures. Aggrecan gene expression did not vary significantly between mediums and three-dimensional system cultures, but in ICM cultures, the monolayer cultures had significantly higher levels of aggrecan gene expression than did either the PCL or pellet cultures. Chondrocytes cultured in PCL scaffolds or pellets with FCM did not proliferate to a great extent but did maintain their differentiated phenotype for 28 days. Levels of cartilage ECM protein synthesis and deposition into the scaffold pores were similar among PCL and pellet cultures grown in FCM and in ICM. In conclusion, chondrocytes seeded into PCL scaffolds, cultured in ICM, efficiently maintained their differentiated phenotype and were able to synthesize cartilage-specific ECM proteins.

Influence of autograft removal on rabbit patellar tendon length

Twelve adult New Zealand white rabbits were randomly divided into two groups. In group 1, 30% of the central mass of the right patellar tendon was removed. In group 2, 60% was removed. The left knees served as controls. The animals were killed 1 year later. The patella-patellar tendon-tibial tuberosity units of all knees were studied using histological and morphometric analysis. In both groups, the tendons had lengthened. Lengthening average was 2.50 mm in group 1 and 8.17 mm in group 2. In both groups, histology revealed poor alignment of the collagen fibres and high cellularity, although the findings in group 1 were nearer the normal histological pattern. The results suggest that removal of significant portions of the patellar tendon leads to lengthening of the resulting tendon. In clinical practice, it seems prudent to pay attention to the dimensions of the patellar tendon when harvesting a graft.

Combined fracture of the talus: Arthroscopic treatment

The purpose of this article is to report the treatment and short-term results of a combined fracture of the talus treated arthroscopically. A 29-year-old man sustained an anterolateral osteochondral grade III fracture of the talus dome associated with a coronal fracture of the body of the talus. This injury was reduced and fixed arthroscopically using cannulated screws. The patient returned to his daily style of living after 3 months time. One year later, the patient remains asymptomatic. Radiography showed neither signs of osteonecrosis nor osteoarthritis of the talus at the 1-year follow-up. Therefore, arthroscopic surgery could be an alternative treatment for this kind of talus fracture.

Ring-shaped lateral meniscus

The existence of abnormal-shaped menisci has been long recognized. The presence of discoid menisci in the human knee is considered to be a congenital malformation with a very low rate of incidence except in Asian populations. Since the publication of Watanabe's Atlas, three types of lateral meniscal abnormalities are generally accepted: the complete and incomplete discoid, as well as the Wrisberg-ligament type meniscus. The present case is the second description of a ring-shaped meniscus on the lateral side of the knee and we propose that this variant be included as a fourth variant in a future classification.

Osteochondritis dissecans: a historical review and its treatment with cannulated screws

The etiology of osteochondritis dissecans and the results of treating the early stages with arthroscopic fixation using cannulated screws is discussed. Arthroscopic surgery was performed on 14 patients with osteochondritis dissecans, and the osteochondral fragment was fixed with one or two screws. A second arthroscopic procedure was necessary to assess the lesion and remove the screws. Ambulation without weight bearing is allowed during the first 2 months postoperatively. Full range of motion is encouraged. The results indicate that all patients returned to their previous sport 3-11 months postsurgery. The authors conclude that fixation with cannulated screws is the ideal method of treating osteochondritis dissecans when the osteochondral fragment is still in its bed.