Midterm Outcomes of Arthroscopic Reduction and Internal Fixation of Anterior Cruciate Ligament Tibial Eminence Avulsion Fractures With K-Wire Fixation.

PURPOSE: To determine the clinical and radiological outcomes of patients who underwent arthroscopic reduction and internal fixation of a tibial eminence avulsion fracture with Kirshner wires (K-wires) at a mean of 8 years following surgery. METHODS: This was a retrospective study with prospectively collected data. Inclusion criteria consisted of patients who underwent arthroscopic reduction and internal fixation of tibial eminence fracture with K-wires between 1989 and 2015 at a minimum of 18 months follow-up. Assessment included the International Knee Documentation Committee Ligament Evaluation, Lysholm Knee Score, and clinical outcomes. Magnetic resonance imaging (MRI) was performed to evaluate the anterior cruciate ligament (ACL) and evidence of osteoarthritis. RESULTS: A total of 48 participants met the inclusion criteria, and 32 were reviewed at a mean of 8 years (range, 18-260 months) after surgery. The mean age at the time of surgery was 24.5 years (10-55 years). Subsequent ACL injury occurred in 5 participants (10.4%) on the index knee and in 1 participant also on the contralateral knee; 86% had a normal examination, and no patients had >5-mm side-to-side difference on instrumented testing. The mean International Knee Documentation Committee subjective score at 8 years was 86 (range, 40-100). On MRI scan assessment for osteoarthritic changes at final follow-up, 82% of participants had no evidence of chondral wear on the medial compartment and 73% had no changes in the lateral compartment according to Magnetic Resonance Image Osteoarthritis Knee Score classification. On MRI scan qualitative assessment of ACL and tibial eminence, 7 participants (32%) were found to have high signal at the fracture site. The mean medial tibial eminence height was 9.2 mm (range, 6.3 mm to 1.31 cm) and the lateral tibial eminence height was an average of 6.7 mm (range, 0.38-0.97 mm). Significant kneeling pain was reported by 8 participants (25%). CONCLUSIONS: This study indicates that internal fixation with K-wires is an acceptable approach to reduce tibial eminence avulsion fractures, providing excellent clinical and radiological outcomes at a minimum of 18 months of follow-up. LEVEL OF EVIDENCE: Level IV, therapeutic case series.

Frog-Leg Test Maneuver for the Diagnosis of Injuries to the Posterolateral Corner of the Knee: A Diagnostic Accuracy Study.

OBJECTIVE: To determine the sensitivity and specificity of a new clinical test for the diagnosis of injuries to the posterolateral corner of the knee by using magnetic resonance imaging (MRI) as the reference standard. DESIGN: Diagnostic accuracy study. SETTING: A tertiary care teaching hospital. PARTICIPANTS: Twelve subjects with chronic instability of the knee and posterolateral corner injury diagnosed by intraoperative findings and 9 subjects without posterolateral corner injury (used as controls). INTERVENTIONS: Injured and uninjured knees were assessed blindly by 2 examiners using a new clinical diagnostic test (the frog-leg test) and the classic varus stress test. MAIN OUTCOME MEASURES: Injuries to the posterolateral corner of the knee identified by the 2 clinical tests. Findings were compared and examined for reproducibility, and kappa statistic was used to assess interobserver agreement. Test results were compared with those of MRI and intraoperative findings to determine diagnostic accuracy. RESULTS: The frog-leg test showed high interobserver agreement (kappa, 0.86), with a high rate (83%-100%) of agreement with the intraoperative diagnosis. The frog-leg test had high sensitivity (91.7%) and specificity (94.5%) for detecting posterolateral corner injuries. The sensitivity of the varus stress test increased from 83.3% to 90.0% when combined with the frog-leg test. CONCLUSIONS: Examiners were able to identify posterolateral corner injuries and differentiate injured from uninjured knees using the frog-leg test, which could potentially be used as an ancillary tool to the varus stress test in diagnosing injuries to the posterolateral corner of the knee. Larger studies are needed to confirm our findings.

Decreasing Posterior Femoral Condyle Offset Improves Intraoperative Correction of Flexion Contracture in Total Knee Arthroplasty.

Multiple intraoperative strategies are described to achieve full extension in total knee arthroplasty, but only a few studies have assessed the effect of the flexion gap on intraoperative improvement in flexion contracture. The aim of this study was to determine whether posterior condylar offset, in isolation, independently affects extension at the time of total knee arthroplasty.Two hundred and seventy-eight patients who underwent total knee arthroplasty for knee osteoarthritis and flexion contracture ≥ 5 degrees between January 2008 and July 2018 were included in this study. Patients with other factors that could affect knee extension at the time of surgery were excluded. We recorded the thickness of posterior femoral condyle bone resected as well as the thickness of the posterior femoral component chosen for each patient. Patients' knee extension was recorded under anesthetic, prior to resection and intraoperatively after total knee replacement.Average thickness of bone resection for the posteromedial femur was 12.64 ± 1.65 mm and for the posterolateral femur was 10.38 ± 1.52 mm. Using a linear regression model, we found that changes in posterior offset and implant downsizing influenced correction of fixed flexion deformity at the time of surgery. When patients had a combined posteromedial and posterolateral offset 2 mm thinner than the thickness of bone resected, there was an average correction of 3.5 degrees of flexion contracture.Our study demonstrated that posterior femoral condyle offset is an independent variable affecting correction of flexion contracture at the time of surgery in a gap balanced cruciate-retaining total knee arthroplasty. This is a level IV evidence study.

Posterior Knee Capsulotomy for the Relief of Patellofemoral Joint Pain: Long-Term Follow-up.

Lack of full extension of the knee is a disabling condition that sometimes needs to be treated by a posterior capsulotomy of the knee. However, it is not clear if the full extension acquired can be kept throughout long-time follow-up. We conducted a retrospective cohort study of 20 patients diagnosed with minimal flexion contracture of the knee who underwent open posterior capsulotomy between 1990 and 2010. All patients (100%) presented with a preoperative Lysholm's score classified as poor or fair (mean = 58.6 ± 13.8, 95% confidence interval [CI]: 52.3-64.9), but 14 patients (70%) experienced an improvement to good or excellent scores (mean = 87.6 ± 8.8, 95% CI: 83.6-91.6) after the follow-up. The mean preoperative angle of fixed flexion was 25.0 ± 9.1 degrees (95% CI: 20.8-29.2), and it decreased to 4.2 ± 4.1 degrees (95% CI: 2.3-6.1) after the follow-up. We conclude that posterior capsulotomy of the knee proved to be an effective procedure to treat properly patients with painful knees secondary to lack of full extension after 10.3 years of follow-up.

Patients with lateral compartment knee osteoarthritis during arthroscopy are at highest risk of subsequent knee arthroplasty.

BACKGROUND: Arthroscopic treatment of knee osteoarthritis has declined, in part due to concerns with conversion to arthroplasty. Some studies have investigated the demographic predictors for conversion to arthroplasty, few have assessed the risk factors within the knee itself. Our aim was to analyse the demographics and anatomical wear features of a large cohort of patients undergoing knee arthroscopy. METHODS: A retrospective analysis of 1760 cases spanning over 17 years undergoing knee arthroscopy was performed. Patients were 36 years or older at time of the index arthroscopy. Each patient received the International Cartilage Regeneration and Joint Preservation Society (ICRS) grade of all regions as well an estimate of the remaining meniscal percentage. Demographic factors as well as intraoperatively collected data were analysed as predictive variables for subsequent conversion to arthroplasty using a multi-step Cox regression analysis. RESULTS: A total of 102 patients (6.2%) were converted to arthroplasty. Age at arthroscopy (hazard ratio (HR) 1.073; 95% confidence interval (CI) 1.058-1.088) and ICRS grade of the lateral tibial plateau (HR 1.166; 95% CI 1.066-1.276) were statistically significant predicting variables for conversion to arthroplasty. CONCLUSIONS: The results of this study indicate that higher ICRS grade of the lateral tibial plateau at arthroscopy is the most significant predictor for conversion to knee arthroplasty, with a hazard equal to an increase in age. The absence of these factors does not justify arthroscopic treatment of patients with knee osteoarthritis. LEVEL OF EVIDENCE: III.

Large osteophyte removal from the posterior femoral condyle significantly improves extension at the time of surgery in a total knee arthroplasty.

Removing osteophytes from the posterior compartment of the femur eliminates the tenting effects on the joint capsule and consequently increases the extension gap in total knee arthroplasty. However, there is no clear association with the size of osteophytes removed and the potential degree of additional extension achieved at time of surgery. AIMS: Correlate the size of posterior osteophytes removed with the degree of extension gained intraoperatively in total knee arthroplasty and develop a radiological classification system to grade these osteophytes. METHODS: Patients who underwent a TKA had pre and post operative sagittal radiographs assessed and classified according to 4 different categories of a proposed classification system. Knee extension was then assessed by a computer navigated system before incision and after implant insertion. Confounding factors were controlled and considered on the analysis. The study was done retrospectively. RESULTS: 147 patients were included in the study. Ninety-three (63.2%) patients had osteophytes on the posterior aspect of the femur completely removed and fifty-four patients (36.8%) did not have radiological evidence of osteophytes on the posterior aspect of the femur. There was a positive and linear correlation (Pearson correlation 0.327, p .005) between osteophyte size and degree of extension corrected at time of surgery. On Multivariate Logistic Regression Analysis, we found that small osteophytes (Grade 1) did not seem to affect the extension, while removing Grade 2 or Grade 3 osteophytes lead to a gain in extension of 2.7 and 4.5° respectively. CONCLUSION: Removing large osteophytes (Grade 2 and Grade 3) from the posterior femoral compartment can be used as an adjuvant strategy to ensure that intraoperative extension is optimal. However removing small osteophytes (Grade 1) should not be expected to affect extension at the time of surgery in TKA and could increase intra-operative time and morbidity.

Relationship between anterior cruciate ligament and anterolateral meniscal root bony attachment: High-resolution 3-T MRI analysis.

BACKGROUND: The tibial bony attachments of the anterior cruciate ligament (ACL) and the anterolateral meniscal root (ALMR) are very close, and drilling the tibial tunnel in ACL reconstruction may damage the ALMR attachment. This study investigated the relationship between the tibial attachment of the ACL and ALMR using high-resolution 3-T magnetic resonance imaging (MRI). METHODS: Twenty healthy subjects (35.8 ±â€¯13.0 years) had 20 knees scanned using high resolution 3-T MRI. The tibial bony attachments of ACL, ALMR, and the tibia were segmented and three-dimensional models were created. The shape, area, and location of each attachment were evaluated using this model. RESULTS: The ACL tibial attachment was elliptical in nine knees (45%), C-shaped in nine knees (45%) and triangle in two knees (10%). The mean values of the ACL vs ALMR tibial attachments were as follows: area, 106.2 ±â€¯21.3 vs 56.2 ±â€¯21.3 mm2; length, 16.8 ±â€¯2.0 vs 11.0 ±â€¯1.8 mm; and width, 6.9 ±â€¯1.3 vs 6.6 ±â€¯1.0 mm. The location of the ACL vs ALMR attachment centres was 46.5 ±â€¯1.7% vs 56.5 ±â€¯1.9% in the medial-lateral direction and 36.3 ±â€¯3.6% vs 36.7 ±â€¯3.5% in the anterior-posterior direction. The distance between the ACL and ALMR centres was 8.1 ±â€¯1.3 mm. CONCLUSIONS: ACL and ALMR tibial attachments were individually distinguished using high resolution 3-T MRI. The short distance between both centres of the attachments may suggest that ALMR can be damaged when the tibial tunnel is drilled in ACL reconstruction.

Kinematic alignment is bone and soft tissue preserving compared to mechanical alignment in total knee arthroplasty.

BACKGROUND: Kinematically aligned (KA) total knee arthroplasty (TKA) has emerged as an alternative approach to the intraoperative alignment targets of mechanically aligned (MA) TKA. While the clinical outcomes of the two philosophies have been investigated, further investigation is required to quantify exactly how the two philosophies differ in their approach to correcting the deformities encountered in osteoarthritic knees such as fixed flexion deformities (FFD) and coronal malalignment. The aim of this paper was to compare MA and KA philosophies in TKA in terms of the intra-operative correction of FFD and coronal malalignment and quantify the way in which each philosophy achieves a well-balanced knee that can reach full extension. METHODS: A retrospective review of prospective data collected from 210 consecutive TKAs performed by a single surgeon between March 2015 and May 2017 was undertaken. MA and KA cases were compared in terms of pre-operative patient deformity and characteristics, intraoperative steps taken to correct FFD (including bony resections, soft tissue releases and components used) and postoperative alignment achieved. RESULTS: One hundred twenty MA and 90 KA TKAs were analysed. There was no significant difference in terms of patient age, gender and preoperative coronal and sagittal deformity between the two cohorts. KA TKAs were able to achieve the same degree of sagittal correction as MA TKAs with less total bony resection (16.7 mm vs. 18.9 mm, p < 0.0001), less soft tissue releases (10% vs. 49.2%, p < 0.0001). This was achieved with a difference in component alignment. The femur was in more valgus (-2.5 vs. -0.03°, p < 0.0001), the tibia in more varus (2.3 vs. 0.3°, p < 0.0001), and the overall alignment slightly more varus in the KA group (1.1 vs. 0.4°, p = 0.007), without significant difference in the proportion of patients within three degrees of a neutral axis. CONCLUSION: This study shows that using a kinematic alignment philosophy in total knee arthroplasty results in the achievement of extension range-of-motion and soft tissue balance goals with less bone resection and less soft tissue release. This allows for bone stock preservation and minimization of trauma due to soft tissue release. Further study is required to correlate these results with patient reported outcomes and determine their clinical significance. LEVEL OF EVIDENCE: III - retrospective cohort study.

Analysis of acetabular version: Retroversion prevalence, age, side and gender correlations.

INTRODUCTION: Studies using conventional radiographical signs and computerized tomography (CT) for retroversion of the acetabulum have reported a prevalence of up to 25%. The purpose of this study was to provide a detailed report on acetabular version, gender, age and side differences in a large cohort. MATERIALS AND METHODS: A total of 404 patients receiving a whole-body CT scan, aged between 16 and 40 years, have been included in the study. The measurement was performed in the transversal plane on three levels: cranial, central and caudal. RESULTS: The retroverted acetabulum on all three levels had a prevalence of 0.25% (95% confidence interval 0-0.7%). The average central anteversion in men was 16.46° (±4.42) and that in women was 19.31° (±5.04) (p < 0.001). Version increases with age, but a cluster analysis showed this to be a trend (p = 0.068). CONCLUSION: Women have a higher average acetabular version than men. Retroversion in a young adult population has a low prevalence when measured with conventional CT. About a tenth of the population has a significantly different contralateral acetabular version. THE TRANSLATIONAL POTENTIAL OF THIS ARTICLE: Global acetabular retroversion has a much lower prevalence than previously reported.

Dual mobility acetabular cups for total hip arthroplasty: advantages and drawbacks.

INTRODUCTION: The dual mobility cup (DMC) concept was proposed by Professor Gilles Bousquet in 1974. Its' aims were to prevent postoperative dislocation, restore the physiological range of motion of the hip, and reduce the stresses at the interface. Since it was created, this design has been modified multiple times to reduce the complication rate, improve implant survival, and expand the indications. AREAS COVERED: The objective of this review is to discuss the advantages and disadvantages of this implant based on its 40-year history and also to propose a range of indications based on published results. This will provide surgeons with a complete overview of DMC. EXPERT COMMENTARY: Published studies on DMC confirm the low dislocation rate. Improvements made to DMC overtime have greatly reduced the complications related to wear, such as aseptic loosening and intraprosthetic dislocation (IPD). According to the literature, the indications have expanded and are no longer limited to revision surgery only. Long-term studies are needed before we can draw formal conclusions and consolidate these promising results.

Intra-articular Anterior Cruciate Ligament Reconstruction With Extra-articular Lateral Tenodesis of the Iliotibial Band.

An increasing concern has been given to the rotation stability of the knee in the setting of an anterior cruciate ligament (ACL) reconstruction. This growing interest stems from a better understanding of the rotational stability of the knee afforded by the identification of the anterolateral ligament. Previously, a residual abnormal pivot-shift test had been found after an anatomic single-band reconstruction of the ACL because of a lack of rotational stability, which may lead to the development of osteoarthritis. Residual instability affects function, especially in high-demand athletes who perform many flexion-rotation movements during sporting activity. The purpose of this Technical Note is to describe our preferred method of intra-articular ACL reconstruction using a hamstring tendon autograft in combination with an extra-articular iliotibial band tenodesis for reinforcement of rotational stability.

Posterior Capsulotomy of the Knee: Treatment of Minimal Knee Extension Deficit.

The loss of knee extension, even if minimal, is disabling and considerably affects the individual's quality of life. This loss of extension can be a consequence of prior surgery, including a previous anterior cruciate ligament reconstruction. Although this loss of extension may be treated through an isolated arthroscopic procedure, a more severe case may warrant an invasive approach. In these cases, a posterior capsulotomy of the knee may be done if all conservative measures have been exhausted. This procedure has been proven to be safe and effective in the re-establishment of full extension in the setting of a minor flexion contracture of the knee. The purpose of this Technical Note was to describe our preferred technique when performing an open posterior capsulotomy of the knee for the treatment of minimal extension deficit.

Comparative study of subtalar arthrodesis after calcaneal frature malunion with autologous bone graft or freeze-dried xenograft.

BACKGROUND: Calcaneal fracture malunion may evolve into arthrosis and severe foot deformities. The aim of this study was to identify differences in bony union following corrective subtalar arthrodesis with interposition of autologous tricortical bone graft or freeze-dried bovine xenograft. METHODS: We prospectively evaluated 12 patients who underwent subtalar arthrodesis, six patients received autografts and 6 received freeze-dried bovine xenografts. After a mean followup of 58 weeks, the patients were clinical assessed using AOFAS scale and the visual analog scale (VAS) for pain and for final radiographic parameters measurement. Two blind raters evaluated the length of time required for solid union of the arthrodesis and graft integration by retrospective radiographic examination. RESULTS: In the autograft group, AOFAS score improved from a preoperative average of 37 to 64 points postoperatively (p = 0.02) and mean VAS score improved from 4.7 to 1.9 (p = 0.028). In the xenograft group, AOFAS score improved from 38 to 74 points (p = 0.02) and VAS from 5.5 to 2.7 (p = 0.046). Solid union was achieved in all cases in the autograft group at an average of 5.3 weeks and in five cases in the xenograft group at 8.8 weeks (p = 0.077). Graft integration occurred after an average of 10.7 weeks in the autograft group and 28.8 weeks in the xenograft group (p = 0.016). CONCLUSION: With the numbers available, no significant difference could be detected in the length of time required for solid union of subtalar arthrodesis between groups, although time to integration of freeze-dried bovine xenografts was statistically higher. Clinical and functional improvement was observed in both groups.

Estudo comparativo de artrodese subtalar após fratura de calcâneo com enxerto ósseo ou xenoenxerto liofilizado / Comparative study of subtalar arthrodesis after calcaneal fracture with autologous bone graft or freeze-dried xenograft

Introdução: A fratura viciosamente consolidada do calcâneo pode evoluir com artrose e deformidades graves do pé. O objetivo deste estudo é identifi car diferenças na consolidação da artrodese subtalar corretiva, com interposição de enxerto ósseo tricortical autólogo ou com xenoenxerto bovino liofi lizado. Métodos: Foram avaliados prospectivamente 12 pacientes submetidos a artrodese subtalar no Hospital de Clínicas de Porto Alegre. Em 6 pacientes utilizou-se enxerto autólogo e em 6, xenoenxerto bovino liofilizado. Após seguimento médio de 58 semanas, realizou-se a avaliação dos pacientes utilizando a escala AOFAS e a escala visual analógica de dor (VAD). Dois avaliadores cegos avaliaram o tempo para a consolidação da artrodese e a integração do enxerto por exames radiográficos. Resultado: O escore AOFAS melhorou entre o pré e pós-operatório, média de 37 para 64 pontos (p=0,02) no grupo controle e de 38 para 74 pontos (p=0,02) no grupo estudo. Assim como a escala VAD melhorou, média de 4,7 para 1,9 (p=0,028) no grupo controle e de 5,5 para 2,7 (p=0,046) no grupo estudo. Houve consolidação da artrodese em todos os casos do grupo controle em um tempo médio de 5,3 semanas e em 5 casos do grupo estudo, em 8,8 semanas (p=0,077). A integração do enxerto ocorreu após uma média de 10,7 semanas e de 28,8 semanas no grupo controle e estudo, respectivamente (p=0,016). Conclusão: Não observamos diferença estatisticamente significativa no tempo para consolidação da artrodese entre os grupos, embora o tempo para integração do xenoenxerto bovino liofilizado seja estatisticamente maior. Houve melhora clínico-funcional em ambos os grupos.

Introduction: Viciously consolidated fracture of the calcaneus can evolve with osteoarthritis and severe foot deformities. The aim of this study is to identify differences in the consolidation of corrective subtalar arthrodesis with interposition of autologous tricortical bone graft or lyophilized bovine xenograft. Methods: We prospectively evaluated 12 patients undergoing subtalar arthrodesis in the Hospital de Clínicas of Porto Alegre. In 6 patients we used autologous graft and in other 6 lyophilized bovine xenograft. After a mean follow-up of 58 weeks, patients were evaluated using the AOFAS scale and a visual analogue pain scale (VAPS). Two blinded evaluators assessed the time for consolidation of the arthrodesis and integration of the graft for radiographic examinations. Result: The AOFAS score improved between the pre- and postoperative periods, a mean of 37 to 64 points (p = 0.02) in the control group and 38 to 74 points (p = 0.02) in the experimental group. VAPS scores improved as well, from a mean of 4.7 to 1.9 (p = 0.028) in the control group and 5.5 to 2.7 (p = 0.046) in the experimental group. There was consolidation of arthrodesis in all of the cases in the control group at a median time of 5.3 weeks, and in 5 cases in the experimental group, at 8.8 weeks (p = 0.077). Graft integration occurred after a mean of 10.7 weeks and 28.8 weeks in the control and experimental groups, respectively (p = 0.016). Conclusion: We did not fi nd a statistically signifi cant difference in the time for arthrodesis consolidation between the groups, although the time for integration of the lyophilized bovine xenograft is statistically higher. There was clinical and functional improvement in both groups.