The Role of Osteotomy for the Treatment of PCL Injuries

Purpose of Review The purposes of this review are to (1) describe the anatomic and biomechanical rationale for high tibial osteotomy (HTO) in the setting of posterior cruciate ligament (PCL) deficiency, (2) review the indications for concomitant HTO and PCL reconstruction, (3) provide guidance for the clinical assessment of the patient with suspected PCL deficiency, and (4) summarize the key surgical steps necessary to attain the appropriate sagittal and coronal plane corrections. Recent Findings The preponderance of available biomechanical data pertaining to the PCL-deficient knee suggests that an increased proximal tibial slope limits posterior tibial translation under axial compressive loads. Moreover, recent clinical data has demonstrated that decreased proximal tibial slope may exacerbate residual anterior-posterior laxity and jeopardize the durability of PCL reconstruction. Thus, in the setting of PCL deficiency, an HTO that increases the posterior tibial slope may be advisable. Summary HTO may be an important treatment adjunct in the surgical management of PCL deficiency. In the setting of chronic injuries and varus malalignment, HTO should be considered in order to ensure a durable ligamentous reconstruction and forestall the progression of secondary osteoarthritis.Univ Pittsburgh, Dept Orthopaed Surg, 3471 Fifth Ave, Pittsburgh, PA 15213 USAUniv Fed Sao Paulo, Orthopaed & Traumatol Sports Ctr CETE, Dept Orthopaed & Traumatol, Paulista Sch Med EPM, Sao Paulo, BrazilAlbert Einstein Coll Med, Bronx, NY 10467 USAUniv Fed Sao Paulo, Orthopaed & Traumatol Sports Ctr CETE, Dept Orthopaed & Traumatol, Paulista Sch Med EPM, Sao Paulo, BrazilWeb of Scienc

Long-Term Survival Analysis and Outcomes of Meniscal Allograft Transplantation With Minimum 10-Year Follow-Up: A Systematic Review

© 2019 Arthroscopy Association of North America Purpose: To investigate the long-term survivorship rates and functional outcomes of meniscal allograft transplantation (MAT) in patients with minimum 10-year postoperative follow-up. Methods: Two reviewers independently searched EMBASE, MEDLINE, and PubMed from database inception for literature related to MAT according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) checklist. Data are reported in a narrative summary fashion with descriptive statistics. Results: Eleven studies with a total of 658 patients and 688 MATs were included. Mean age of patients was 33.1 years (range 14-66), of whom 63% were male. Mean survivorship rates were 73.5% at 10-year and 60.3% at 15-year follow-up, with 2 studies reporting 19- and 24-year survivorship of 50% and 15.1%, respectively. Pre- and postoperative Lysholm scores ranged from 36 to 60.5 and 61 to 75, respectively. Pre- and postoperative Tegner scores ranged from 1 to 3 and 2.5 to 4.6, respectively. Postoperative Knee injury and Osteoarthritis Outcome Score subset scores were as follows: Pain: 61.6 to 76.3; Symptoms: 57.9 to 61.8; Function in Daily Living: 68.5 to 79.9; Sport and Recreation: 33.9 to 49.3; Quality of Life: 37.3 to 45.9. Postoperative International Knee Documentation Committee scores ranged from 46 to 77. Regarding surgical technique, 194 MAT bone-fixation technique (53.8%) and 165 MAT suture-only fixation techniques (46.2%) were reported. The most common type of allograft used was cryopreserved (54.5% of the allografts). The most frequent concomitant procedures performed with MAT were to address chondral (20.8% of the cases) and ligament injuries (12.4% of the cases), and realignment procedures (9.4% of the cases). The most common complications observed that were not directly related to concomitant procedures were meniscal allograft partial tears (11.1%), arthrofibrosis (3.6%), and infection (2.0%). Several criteria were used among studies to define failure of MAT, the most common parameters being removal of meniscal allograft (8/11 studies) and conversion to total knee arthroplasty (7/11 studies). Conclusions: MAT can yield good long-term survivorship rates, with 73.5% and 60.3% of allografts remaining functional after 10 and 15 years, respectively. Functional outcomes 10 years after MAT were fair and improved compared with preoperative scores. Level of Evidence: Level IV, systematic review of Level III and IV studies

Intercondylar Notch Measurement During Arthroscopy and on Preoperative Magnetic Resonance Imaging

Small intercondylar notch size is associated with increased risk of anterior cruciate ligament (ACL) injuries and increased difficulty of ACL reconstruction. When encountering a small notch during surgery, some surgeons may resort to a notchplasty, which has been shown to have associated morbidity. The ability to predict notch size on preoperative imaging could allow the orthopaedic surgeon to anticipate surgical difficulty such as an oversized graft and graft impingement and possibly avoid a notchplasty. Many methods have been proposed for measuring intercondylar notch size, but they do not correlate with intraoperative measurements or they utilize computed tomography scanning, which is not readily obtained before ACL reconstruction. The purpose of this study was to develop a method of notch measurement on preoperative radiography and magnetic resonance imaging that match intraoperative arthroscopic measurements. The method presented here can be used to identify narrow intercondylar notches, prepare for potential intraoperative challenges, and formulate surgical plans such as for graft choice in individualized ACL reconstruction

Rotatory Knee Laxity Exists on a Continuum in Anterior Cruciate Ligament Injury

Abstract Background: The purpose of this investigation was to compare the magnitude of rotatory knee laxity in patients with a partial anterior cruciate ligament (ACL) tear, those with a complete ACL tear, and those who had undergone a failed ACL reconstruction. It was hypothesized that rotatory knee laxity would increase with increasing injury grade, with knees with partial ACL tears demonstrating the lowest rotatory laxity and knees that had undergone failed ACL reconstruction demonstrating the highest rotatory laxity. Methods: A prospective multicenter study cohort of 354 patients who had undergone ACL reconstruction between 2012 and 2018 was examined. All patients had both injured and contralateral healthy knees evaluated using standardized, preoperative quantitative pivot shift testing, determined by a validated, image-based tablet software application and a surface-mounted accelerometer. Quantitative pivot shift was compared with the contralateral healthy knee in 20 patients with partial ACL tears, 257 patients with complete ACL tears, and 27 patients who had undergone a failed ACL reconstruction. Comparisons were made using 1-way analysis of variance (ANOVA) with post hoc 2-sample t tests with Bonferroni correction. Significance was set at p < 0.05. Results: There were stepwise increases in side-to-side differences in quantitative pivot shift in terms of lateral knee compartment translation for patients with partial ACL tears (mean [and standard deviation], 1.4 \ub1 1.5 mm), those with complete ACL tears (2.5 \ub1 2.1 mm), and those who had undergone failed ACL reconstruction (3.3 \ub1 1.9 mm) (p = 0.01) and increases in terms of lateral compartment acceleration for patients with partial ACL tears (0.7 \ub1 1.4 m/s2), those with complete ACL tears (2.3 \ub1 3.1 m/s2), and those who had undergone failed ACL reconstruction (2.4 \ub1 5.5 m/s2) (p = 0.01). A significant difference in lateral knee compartment translation was found when comparing patients with partial ACL tears and those with complete ACL tears (1.2 \ub1 2.1 mm [95% confidence interval (CI), 0.2 to 2.1 mm]; p = 0.02) and patients with partial ACL tears and those who had undergone failed ACL reconstruction (1.9 \ub1 1.7 mm [95% CI, 0.8 to 2.9 mm]; p = 0.001), but not when comparing patients with complete ACL tears and those who had undergone failed ACL reconstruction (0.8 \ub1 2.1 [95% CI, 120.1 to 1.6 mm]; p = 0.09). Increased lateral compartment acceleration was found when comparing patients with partial ACL tears and those with complete ACL tears (1.5 \ub1 3.0 m/s2 [95% CI, 0.8 to 2.3 m/s2]; p = 0.0002), but not when comparing patients with complete ACL tears and those who had undergone failed ACL reconstruction (0.1 \ub1 3.4 m/s2 [95% CI, 122.2 to 2.4 m/s2]; p = 0.93) or patients with partial ACL tears and those who had undergone failed ACL reconstruction (1.7 \ub1 4.2 m/s2 [95% CI, 120.7 to 4.0 m/s2]; p = 0.16). An increasing lateral compartment translation of the contralateral, ACL-healthy knee was found in patients with partial ACL tears (0.8 mm), those with complete ACL tears (1.2 mm), and those who had undergone failed ACL reconstruction (1.7 mm) (p < 0.05). Conclusions: A progressive increase in rotatory knee laxity, defined by side-to-side differences in quantitative pivot shift, was observed in patients with partial ACL tears, those with complete ACL tears, and those who had undergone failed ACL reconstruction. These results may be helpful when assessing outcomes and considering indications for the management of high-grade rotatory knee laxity. Level of Evidence: Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence

Store-Operated Ca2+ Entry Controls Induction of Lipolysis and the Transcriptional Reprogramming to Lipid Metabolism

Ca2+ signals were reported to control lipid homeostasis, but the Ca2+ channels and pathways involved are largely unknown. Store-operated Ca2+ entry (SOCE) is a ubiquitous Ca2+ influx pathway regulated by stromal interaction molecule 1 (STIM1), STIM2, and the Ca2+ channel ORAI1. We show that SOCE-deficient mice accumulate pathological amounts of lipid droplets in the liver, heart, and skeletal muscle. Cells from patients with loss-of-function mutations in STIM1 or ORAI1 show a similar phenotype, suggesting a cellintrinsic role for SOCE in the regulation of lipid metabolism. SOCE is crucial to induce mobilization of fatty acids from lipid droplets, lipolysis, and mitochondrial fatty acid oxidation. SOCE regulates cyclic AMP production and the expression of neutral lipases as well as the transcriptional regulators of lipid metabolism, peroxisome proliferator-activated receptor gamma coactivator 1 alpha (PGC-1 alpha), and peroxisome proliferator- activated receptor alpha (PPAR alpha). SOCE-deficient cells upregulate lipophagy, which protects them from lipotoxicity. Our data provide evidence for an important role of SOCE in lipid metabolism

ORAI1 mutations abolishing store-operated Ca

BACKGROUND: Store-operated Ca OBJECTIVE: We performed molecular and immunologic analysis of patients with CID, anhidrosis, and ectodermal dysplasia of unknown etiology. METHODS: We performed DNA sequencing of the ORAI1 gene, modeling of mutations on ORAI1 crystal structure, analysis of ORAI1 mRNA and protein expression, SOCE measurements, immunologic analysis of peripheral blood lymphocyte populations by using flow cytometry, and histologic and ultrastructural analysis of patient tissues. RESULTS: We identified 3 novel autosomal recessive mutations in ORAI1 in unrelated kindreds with CID, autoimmunity, ectodermal dysplasia with anhidrosis, and muscular dysplasia. The patients were homozygous for p.V181SfsX8, p.L194P, and p.G98R mutations in the ORAI1 gene that suppressed ORAI1 protein expression and SOCE in the patients\u27 lymphocytes and fibroblasts. In addition to impaired T-cell cytokine production, ORAI1 mutations were associated with strongly reduced numbers of invariant natural killer T and regulatory T (Treg) cells and altered composition of γδ T-cell and natural killer cell subsets. CONCLUSION: ORAI1 null mutations are associated with reduced numbers of invariant natural killer T and Treg cells that likely contribute to the patients\u27 immunodeficiency and autoimmunity. ORAI1-deficient patients have dental enamel defects and anhidrosis, representing a new form of anhidrotic ectodermal dysplasia with immunodeficiency that is distinct from previously reported patients with anhidrotic ectodermal dysplasia with immunodeficiency caused by mutations in the nuclear factor κB signaling pathway (IKBKG and NFKBIA)

High-grade rotatory knee laxity may be predictable in ACL injuries

Purpose: Lateral compartment acceleration and translation have been used to quantify rotatory knee laxity in the setting of anterior cruciate ligament (ACL) injury; however, their relationship remains elusive. The purpose of this study was to examine the correlation between lateral compartment acceleration and translation during pivot shift testing. It was hypothesized that a correlation would exist in ACL-injured and uninjured knees, irrespective of sex, but would be greatest in knees with combined ACL and lateral meniscus tear. Methods: Seventy-seven patients (34 females, 25.2 ± 9.0 years) undergoing primary single-bundle ACL reconstruction were prospectively enrolled in a 2-year study across four international centers. Patients underwent preoperative examination under anesthesia of the injured and uninjured knee using Image Analysis software and surface mounted accelerometer. Results: A moderate correlation between lateral compartment acceleration and translation was observed in ACL-injured knees [ρ = 0.36, p < 0.05), but not in uninjured knees (ρ = 0.17, not significant (n.s.)]. A moderate correlation between acceleration and translation was demonstrated in ACL-injured knees with lateral meniscus tears (ρ = 0.53, p < 0.05), but not in knees with isolated ACL-injury (ρ = 0.32, n.s.), ACL and medial meniscus tears (ρ = 0.14, n.s.), or ACL and combined medial and lateral meniscus tears (ρ = 0.40, n.s.). A moderate correlation between acceleration and translation was seen in males (ρ = 0.51, p < 0.05), but not in females (ρ = 0.21, n.s.). Largest correlations were observed in males with ACL and lateral meniscus tears (ρ = 0.75, p < 0.05). Conclusion: Lateral compartment acceleration and translation were moderately correlated in ACL-injured knees, but largely correlated in males with combined ACL and lateral meniscus tears. ACL and lateral meniscus injury in males might, therefore, be suspected when both lateral compartment acceleration and translation are elevated. Surgeons should have a greater degree of suspicion for high-grade rotatory knee laxity in ACL-injured males with concomitant lateral meniscus tears. Future studies should investigate how these two distinct components of rotatory knee laxity—lateral compartment acceleration and translation—are correlated with patient outcomes and affected by ACL surgery. Level of evidence: Prospective cohort study; Level of evidence II