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.

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.

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.

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.

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.

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.