Plastic and Heritable Components of Phenotypic Variation in Nucella lapillus: An Assessment Using Reciprocal Transplant and Common Garden Experiments

Assessment of plastic and heritable components of phenotypic variation is crucial for understanding the evolution of adaptive character traits in heterogeneous environments. We assessed the above in relation to adaptive shell morphology of the rocky intertidal snail Nucella lapillus by reciprocal transplantation of snails between two shores differing in wave action and rearing snails of the same provenance in a common garden. Results were compared with those reported for similar experiments conducted elsewhere. Microsatellite variation indicated limited gene flow between the populations. Intrinsic growth rate was greater in exposed-site than sheltered-site snails, but the reverse was true of absolute growth rate, suggesting heritable compensation for reduced foraging opportunity at the exposed site. Shell morphology of reciprocal transplants partially converged through plasticity toward that of native snails. Shell morphology of F2s in the common garden partially retained characteristics of the P-generation, suggesting genetic control. A maternal effect was revealed by greater resemblance of F1s than F2s to the P-generation. The observed synergistic effects of plastic, maternal and genetic control of shell-shape may be expected to maximise fitness when environmental characteristics become unpredictable through dispersal

Opening- and closing-wedge distal femoral osteotomy: a systematic review of outcomes for isolated lateral compartment osteoarthritis

Background: Lateral compartment osteoarthritis of the knee can be a challenging pathology in the younger, active population due to limited treatment options and high patient expectations. Distal femoral osteotomy (DFO) has been reported to be a potential treatment option. Purpose: To perform a systematic review on the survival, outcomes, and complications of DFO for treatment of genu valgum with concomitant lateral compartment osteoarthritis of the knee. Study Design: Systematic review; Level of evidence, 4. Methods: A systematic review of the literature was performed using the Cochrane Database of Systematic Reviews, the Cochrane Central Registry of Controlled Trials, PubMed, and MEDLINE from 1980 to present. Inclusion criteria were as follows: outcomes of opening- and closing-wedge DFOs performed for treatment of genu valgum with concomitant lateral compartment osteoarthritis of the knee, English language, minimum 2-year follow-up, and human studies. Data abstracted from the selected studies included type of osteotomy (opening vs closing), survival rate, patient-reported and radiographic outcomes, and complications. Results: Fourteen studies met the inclusion criteria and were considered for the review. A total of 9 closing-wedge and 5 opening-wedge DFO studies were included. All were retrospective studies and reported good to excellent patient-reported outcomes after DFO. Survival decreased with increasing time from surgery, with 1 study reporting a 100% survival rate at 6.5 years, compared with 21.5% at 20 years in another study. A low rate of complications was reported throughout the review. Conclusion: Highly heterogeneous literature exists for both opening- and closing-wedge DFOs for the treatment of isolated lateral compartment osteoarthritis with valgus malalignment. A mean survival rate of 80% at 10-year follow-up was reported, supporting that this procedure can be a viable treatment option to delay or reduce the need for joint arthroplasty. A low complication rate was observed, with symptomatic hardware being the most prevalent postoperative complication

Anatomic Arthroscopic Ligamentum Teres Reconstruction for Hip Instability

There has been growing interest in recent years on the functional importance of the ligamentum teres and its role in hip stability. Partial or complete tearing has previously been treated with debridement or radiofrequency ablation with good results; however, a subset of patients will continue to experience persistent pain or instability with injury to this structure. Advances in arthroscopic instruments and techniques have led to our ability to provide improved care for these patients by performing a ligamentum teres reconstruction. The purpose of this technical note is to describe our method of ligamentum teres reconstruction with a tibialis anterior allograft

Arthroscopic Acromioclavicular Joint Reconstruction Using Knotless Coracoclavicular Fixation and Soft-Tissue Anatomic Coracoclavicular Ligament Reconstruction

Acromioclavicular joint injuries are one of the most common shoulder injuries, and there are a variety of treatment options. Recently, there have been newer arthroscopic techniques that have addressed coracoid and clavicle fracture risk by using a knotted suture-button fixation through a single, small bone tunnel with additional looped soft-tissue graft stabilization. Although clinical outcomes have been good to excellent, there have still been instances of knot and hardware irritation. The described technique builds on the latest advances and achieves an anatomic coracoclavicular (CC) reconstruction through a single knotless CC fixation device with additional soft-tissue allograft reconstruction of the CC ligaments. This technique minimizes the risks of coracoid and clavicle fractures and knot and hardware irritation while maintaining excellent stability

The Quebec City Slider: A Technique for Capsular Closure and Plication in Hip Arthroscopy

Biomechanical and clinical studies have shown that the hip joint capsule plays an important role in maintaining stability and hip mechanics, including rotation and translation. The recent literature has shown that capsule closure after hip arthroscopy helps to restore stability. Without restoration of the native anatomy, the hip joint may translate when patients engage in activities that place force across the hip, leading to either microinstability or frank dislocation. The purpose of this note is to describe our preferred technique of capsular closure or plication during hip arthroscopy

Anterolateral Ligament Reconstruction Technique: An Anatomic-Based Approach

Restoration of anteroposterior laxity after an anterior cruciate ligament reconstruction has been predictable with traditional open and endoscopic techniques. However, anterolateral rotational stability has been difficult to achieve in a subset of patients, even with appropriate anatomic techniques. Therefore, differing techniques have attempted to address this rotational laxity by augmenting or reconstructing lateral-sided structures about the knee. In recent years, there has been a renewed interest in the anterolateral ligament as a potential contributor to residual anterolateral rotatory instability in anterior cruciate ligament–deficient patients. Numerous anatomic and biomechanical studies have been performed to further define the functional importance of the anterolateral ligament, highlighting the need for surgical techniques to address these injuries in the unstable knee. This article details our technique for an anatomic anterolateral ligament reconstruction using a semitendinosus tendon allograft

Opening- and closing-wedge distal femoral osteotomy: a systematic review of outcomes for isolated lateral compartment osteoarthritis

© The Author(s) 2016© 2016 The Author(s). This is an Open Access article.Background: Lateral compartment osteoarthritis of the knee can be a challenging pathology in the younger, active population due to limited treatment options and high patient expectations. Distal femoral osteotomy (DFO) has been reported to be a potential treatment option. Purpose: To perform a systematic review on the survival, outcomes, and complications of DFO for treatment of genu valgum with concomitant lateral compartment osteoarthritis of the knee. Study Design: Systematic review; Level of evidence, 4. Methods: A systematic review of the literature was performed using the Cochrane Database of Systematic Reviews, the Cochrane Central Registry of Controlled Trials, PubMed, and MEDLINE from 1980 to present. Inclusion criteria were as follows: outcomes of opening- and closing-wedge DFOs performed for treatment of genu valgum with concomitant lateral compartment osteoarthritis of the knee, English language, minimum 2-year follow-up, and human studies. Data abstracted from the selected studies included type of osteotomy (opening vs closing), survival rate, patient-reported and radiographic outcomes, and complications. Results: Fourteen studies met the inclusion criteria and were considered for the review. A total of 9 closing-wedge and 5 opening-wedge DFO studies were included. All were retrospective studies and reported good to excellent patient-reported outcomes after DFO. Survival decreased with increasing time from surgery, with 1 study reporting a 100% survival rate at 6.5 years, compared with 21.5% at 20 years in another study. A low rate of complications was reported throughout the review. Conclusion: Highly heterogeneous literature exists for both opening- and closing-wedge DFOs for the treatment of isolated lateral compartment osteoarthritis with valgus malalignment. A mean survival rate of 80% at 10-year follow-up was reported, supporting that this procedure can be a viable treatment option to delay or reduce the need for joint arthroplasty. A low complication rate was observed, with symptomatic hardware being the most prevalent postoperative complication.Seksjon for idrettsmedisinske fag / Department of Sports Medicin

Anterior Horn Meniscal Repair Using an Outside-In Suture Technique

The menisci are important structures within the knee that play a critical role in maintaining proper stability, load distribution, and joint lubrication. Injury to the menisci has been found to significantly alter the complex biomechanics of the knee, and thus affect the health and longevity of the native joint. Tears involving the anterior horn are increasingly recognized as an important pathology. Although early treatment of meniscal tears focused primarily on removal of the injured tissue, recent attention on the long-term consequences of partial or total meniscectomy has led to increased attempts at meniscus repair whenever possible. Because of the location of anterior horn tears and the technical difficulty in accessing this location arthroscopically, an outside-in repair technique is ideal for treatment of these lesions. This technical note details our surgical technique of outside-in repair of anterior horn meniscal tears

Anterior Meniscal Root Repair Using a Transtibial Double-Tunnel Pullout Technique

The menisci are important structures within the knee and play a critical role in maintaining proper stability, load distribution, and joint lubrication. Injury to these structures can significantly alter the complex biomechanics of the knee and thus affect the health and longevity of the joint. Meniscal root tears are increasingly recognized as an important pathologic condition that results in a nonfunctional meniscus if not properly repaired. Whereas early treatment of meniscal tears traditionally focused on removal of the injured tissue, recent attention on the long-term consequences of partial or total meniscectomy has led to increased attempts at meniscal repair whenever possible. This article details our anatomic anterior root repair procedure using a transtibial double-tunnel pullout technique