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1.
Hortic Res ; 10(11): uhad207, 2023 Nov.
Article in English | MEDLINE | ID: mdl-38023471

ABSTRACT

In the decades since the first cannabinoids were identified by scientists, research has focused almost exclusively on the function and capacity of cannabinoids as medicines and intoxicants for humans and other vertebrates. Very little is known about the adaptive value of cannabinoid production, though several hypotheses have been proposed including protection from ultraviolet radiation, pathogens, and herbivores. To test the prediction that genotypes with greater concentrations of cannabinoids will have reduced herbivory, a segregating F2 population of Cannabis sativa was leveraged to conduct lab- and field-based bioassays investigating the function of cannabinoids in mediating interactions with chewing herbivores. In the field, foliar cannabinoid concentration was inversely correlated with chewing herbivore damage. On detached leaves, Trichoplusia ni larvae consumed less leaf area and grew less when feeding on leaves with greater concentrations of cannabinoids. Scanning electron and light microscopy were used to characterize variation in glandular trichome morphology. Cannabinoid-free genotypes had trichomes that appeared collapsed. To isolate cannabinoids from confounding factors, artificial insect diet was amended with cannabinoids in a range of physiologically relevant concentrations. Larvae grew less and had lower rates of survival as cannabinoid concentration increased. These results support the hypothesis that cannabinoids function in defense against chewing herbivores.

2.
Plant Physiol ; 190(4): 2557-2578, 2022 11 28.
Article in English | MEDLINE | ID: mdl-36135793

ABSTRACT

Water availability influences all aspects of plant growth and development; however, most studies of plant responses to drought have focused on vegetative organs, notably roots and leaves. Far less is known about the molecular bases of drought acclimation responses in fruits, which are complex organs with distinct tissue types. To obtain a more comprehensive picture of the molecular mechanisms governing fruit development under drought, we profiled the transcriptomes of a spectrum of fruit tissues from tomato (Solanum lycopersicum), spanning early growth through ripening and collected from plants grown under varying intensities of water stress. In addition, we compared transcriptional changes in fruit with those in leaves to highlight different and conserved transcriptome signatures in vegetative and reproductive organs. We observed extensive and diverse genetic reprogramming in different fruit tissues and leaves, each associated with a unique response to drought acclimation. These included major transcriptional shifts in the placenta of growing fruit and in the seeds of ripe fruit related to cell growth and epigenetic regulation, respectively. Changes in metabolic and hormonal pathways, such as those related to starch, carotenoids, jasmonic acid, and ethylene metabolism, were associated with distinct fruit tissues and developmental stages. Gene coexpression network analysis provided further insights into the tissue-specific regulation of distinct responses to water stress. Our data highlight the spatiotemporal specificity of drought responses in tomato fruit and indicate known and unrevealed molecular regulatory mechanisms involved in drought acclimation, during both vegetative and reproductive stages of development.


Subject(s)
Solanum lycopersicum , Solanum lycopersicum/metabolism , Fruit/metabolism , Transcriptome/genetics , Gene Expression Regulation, Plant , Dehydration/genetics , Dehydration/metabolism , Plant Proteins/genetics , Plant Proteins/metabolism , Epigenesis, Genetic
3.
Arthroscopy ; 37(8): 2397-2398, 2021 08.
Article in English | MEDLINE | ID: mdl-34353551

ABSTRACT

Since the introduction of rotator cuff repair in the beginning of the 20th century, there have been significant advances in the surgical techniques and improvement in patient outcomes. However, controversy remains regarding the best method for tendon repair, including implant choice, ideal suture construct, and the potential benefits of supplemental biologic additives in order to achieve repair with the best opportunity for healing. The "SCOI Row" technique has been refined over three decades with extensive application and consistently good outcomes. Our technique uses a single row of anchors, triple loaded with a high-strength suture maximizing the number of sutures passed through the tendon to repair the rotator cuff arthroscopically. These anchors are placed 3-4 millimeters from the articular cartilage, providing strong anchorage and a low-tension repair. Debridement of devitalized tendon and only incorporating healthy tendon into the repair is imperative. The biology of the repair is enhanced with bone marrow vents created via microfracture of the greater tuberosity, forming the "Crimson Duvet" or bone marrow super-clot that will envelope the repair site. The bone marrow vents deliver marrow elements, including growth factors and mesenchymal cells that will help to regenerate the footprint of the rotator cuff. This repair construct has been evaluated biomechanically by other investigators and is favorable, as compared to dual row repairs. Our outcomes show greater than 90 % healing rate on postoperative magnetic resonance imaging and excellent patient-reported outcomes.


Subject(s)
Rotator Cuff Injuries , Suture Anchors , Biomechanical Phenomena , Humans , Rotator Cuff/surgery , Rotator Cuff Injuries/surgery , Suture Techniques , Sutures
4.
ACS Appl Mater Interfaces ; 13(25): 29585-29601, 2021 Jun 30.
Article in English | MEDLINE | ID: mdl-34137599

ABSTRACT

Highly dispersed iron-based quantum dots (QDs) onto powdered Vulcan XC-72R substrate were successfully electrodeposited by the rotating disk slurry electrodeposition (RoDSE) technique. Our findings through chemical physics characterization revealed that the continuous electron pathway interaction between the interface metal-carbon is controlled. The rotating ring-disk electrode (RRDE) and the prototype generation unit (PGU) of in-situ H2O2 generation in fuel cell experiments revealed a high activity for the oxygen reduction reaction (ORR) via two-electron pathway. These results establish the Fe/Vulcan catalyst at a competitive level for space and terrestrial new materials carriers, specifically for the in-situ H2O2 production. Transmission electron microscopy (TEM) analysis reveals the well-dispersed Fe-based quantum dots with a particle size of 4 nm. The structural and chemical-physical characterization through induced coupled plasma-optical emission spectroscopy (ICP-OES), transmission scanning electron microscopy (STEM), X-ray diffraction (XRD), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), and X-ray absorption spectroscopy (XAS); reveals that, under atmospheric conditions, our quantum dots system is a Fe2+/3+/Fe3+ combination. The QDs oxidation state tunability was showed by the applied potential. The obtention of H2O2 under the compatibility conditions of the drinking water resources available in the International Space Station (ISS) enhances the applicability of this iron- and carbon-based materials for in-situ H2O2 production in future space scenarios. Terrestrial and space abundance of iron and carbon, combined with its low toxicity and high stability, consolidates this present work to be further extended for the large-scale production of Fe-based nanoparticles for several applications.

5.
Arthroscopy ; 37(1): 28-37, 2021 01.
Article in English | MEDLINE | ID: mdl-32805317

ABSTRACT

PURPOSE: The primary purpose of this study was to evaluate the repair integrity on magnetic resonance imaging (MRI), and secondarily, clinical outcomes, of medium to large (2-4 cm) rotator cuff tears treated using an arthroscopic triple-loaded medially based single-row repair technique augmented laterally with bone marrow vents. METHODS: This is a retrospective outcomes study of patients with full-thickness medium to large (2-4 cm) rotator cuff tears repaired by 4 surgeons at a single institution over a 2-year period with a minimum of 24 months' follow-up. A single-row repair with tension-minimizing medially based triple-loaded anchors and laterally placed bone marrow vents was used. Patients completed a satisfaction and pain survey, the Western Ontario Rotator Cuff index questionnaire, and a Short Form-36 version 2 survey to evaluate clinical outcomes. MRI was obtained at a minimum of 24 months follow-up to assess repair integrity. RESULTS: A total of 64 males and 27 females with a mean age of 59.7 (range, 34-82) were included. The mean tear size was 2.6 cm in anteroposterior dimension, treated with a mean of 2.2 anchors. Eighty-three of 91 shoulders (91%) reported being completely satisfied with their result. The median Western Ontario Rotator Cuff score was 95.2% of normal, with a significant difference found between those with an intact repair and those with a full-thickness recurrent defect (median, 95.9% vs. 73.8%; P = .003). Postoperative MRI obtained at a median of 32 months (range, 24-48) demonstrated an intact repair in 84 of 91 shoulders (92%), with failure defined as a full-thickness defect of the tendon. CONCLUSIONS: Arthroscopic repair of medium to large rotator cuff tears using triple-loaded medially based single-row repair augmented with marrow vents resulted in a 92% healing rate by MRI and excellent patient-reported outcomes LEVEL OF EVIDENCE: Level IV, retrospective case series.


Subject(s)
Arthroscopy/methods , Bone Marrow/surgery , Rotator Cuff Injuries/surgery , Rotator Cuff/surgery , Adult , Aged , Aged, 80 and over , Female , Humans , Magnetic Resonance Imaging , Male , Middle Aged , Postoperative Period , Recurrence , Retrospective Studies , Rupture/surgery , Shoulder/surgery , Suture Techniques , Tendons/surgery , Treatment Outcome
6.
Int J Exerc Sci ; 13(5): 1167-1178, 2020.
Article in English | MEDLINE | ID: mdl-32922645

ABSTRACT

The purpose of this study was to measure intrinsic motivation following the implementation of motivational coaching strategies in a semester long personalized adult fitness program. Sixty individuals (40 female/ 20 male, age= 48 ± 15 yrs) participated as clients in an undergraduate exercise training program led by student trainers at Taylor University. The program took place during two consecutive semesters, therefore subject participation ranged from one to two semesters. In addition to personalized exercise prescription, student trainers implemented motivational strategies using a motivational coaching guide aimed at increasing individuals' overall intrinsic motivation. Trainers utilized a coaching checklist to record the motivational strategies used with their client each session. Intrinsic motivation was assessed before and after each program semester using an Intrinsic Motivation Inventory (IMI) and Motivational Client Scale (MCS). Clients' scores on the IMI increased from 3.38 ± 0.37 to 3.58 ± 0.31 (p<0.001; d= 0.587). Particularly, perceived competence increased from 3.01 ± 0.52 to 3.41 ± 0.49 (p<0.001; d= 0.793). Correspondingly, MCS scores also increased from 3.47 ± 0.72 to 3.87 ± 0.60 (p<0.001; d= 0.608). Specifically, clients' response to challenge increased from 3.48 ± 0.98 to 4.15 ± 0.65 (p<0.001; d=0.809). Our data indicate that it is possible to improve intrinsic motivation by implementing motivational strategies into a supervised adult fitness program. This finding suggests motivational coaching may be an important part of a standard training protocol for fitness trainers to help combat a public health concern: initiation and adherence to exercise.

7.
J Shoulder Elbow Surg ; 29(7S): S73-S79, 2020 Jul.
Article in English | MEDLINE | ID: mdl-32643611

ABSTRACT

BACKGROUND: The purpose of this study was to assess the midterm clinical and ultrasonographic outcomes of a new all arthroscopic supraglenoid origin-preserving tenodesis technique of the long head of the biceps (LHB) brachii tendon in the setting of small to medium-sized rotator cuff repairs. MATERIALS AND METHODS: Thirty patients (33 shoulders) meeting inclusion criteria were identified who underwent LHB tenodesis with this technique in the setting of small to medium-sized rotator cuff repair at a mean age at surgery of 65.6 years between 2015 and 2017. Rotator cuff tears were repaired using the Southern California Orthopedic Institute (SCOI) row technique. The biceps tenodesis was incorporated into the anterior anchor of the rotator cuff repair after bony groove preparation, including débridement and bone vent placement. Frayed edges of the biceps tendon were gently débrided, but the intra-articular glenoid attachment was left intact. Patients were assessed at follow-up by clinical and ultrasonographic examination, as well as a satisfaction questionnaire, the American Shoulder and Elbow Surgeons Standardized Shoulder Assessment Form (ASES) score and visual analog scale (VAS) score. RESULTS: Mean follow-up was 32.9 months for the 27 patients (30 shoulders), resulting in a 91% follow-up. Average ASES score was 94.4. Average patient-reported satisfaction with shoulder function was 9.4 of 10 and with biceps contour was 9.9 of 10. Average VAS score was 0.6 of 10, and 73% of patients reported a VAS score of 0. Ultrasonography demonstrated an intact biceps tendon in 27 of 28 shoulders and an intact supraspinatus tendon in all 28 shoulders. Mean range of motion was 170° in forward flexion, 169° in abduction, 49° in external rotation, and to thoracic vertebrae 12 in internal rotation. Mean muscle grading during Jobe test was 4.8 of 5. There were no intraoperative complications. No patients required revision surgery. CONCLUSIONS: In situ arthroscopic biceps tenodesis with maintenance of the glenoid attachment incorporated into rotator cuff repair yields a high rate of healing and consistently excellent functional and cosmetic outcomes as well as patient satisfaction while saving surgical time and cost.


Subject(s)
Rotator Cuff Injuries/surgery , Rotator Cuff/surgery , Shoulder Joint/physiopathology , Tenodesis/methods , Adult , Aged , Aged, 80 and over , Arthroplasty/methods , Arthroscopy/methods , Female , Follow-Up Studies , Humans , Male , Middle Aged , Range of Motion, Articular , Reoperation , Rotator Cuff/physiopathology , Rotator Cuff Injuries/diagnostic imaging , Rotator Cuff Injuries/physiopathology , Shoulder Joint/diagnostic imaging
8.
Arthroscopy ; 34(10): 2763-2764, 2018 10.
Article in English | MEDLINE | ID: mdl-30286876

ABSTRACT

The anterosuperior rotator interval portal for SLAP repair anchor placement is the perfect balance between obtaining the proper anchor trajectory and respecting the rotator cuff integrity.


Subject(s)
Rotator Cuff Injuries , Shoulder Joint , Tendon Injuries , Arthroscopy , Cadaver , Humans
9.
Sci Rep ; 8(1): 4530, 2018 03 14.
Article in English | MEDLINE | ID: mdl-29540740

ABSTRACT

Microphysiological systems (MPSs) are in vitro models that capture facets of in vivo organ function through use of specialized culture microenvironments, including 3D matrices and microperfusion. Here, we report an approach to co-culture multiple different MPSs linked together physiologically on re-useable, open-system microfluidic platforms that are compatible with the quantitative study of a range of compounds, including lipophilic drugs. We describe three different platform designs - "4-way", "7-way", and "10-way" - each accommodating a mixing chamber and up to 4, 7, or 10 MPSs. Platforms accommodate multiple different MPS flow configurations, each with internal re-circulation to enhance molecular exchange, and feature on-board pneumatically-driven pumps with independently programmable flow rates to provide precise control over both intra- and inter-MPS flow partitioning and drug distribution. We first developed a 4-MPS system, showing accurate prediction of secreted liver protein distribution and 2-week maintenance of phenotypic markers. We then developed 7-MPS and 10-MPS platforms, demonstrating reliable, robust operation and maintenance of MPS phenotypic function for 3 weeks (7-way) and 4 weeks (10-way) of continuous interaction, as well as PK analysis of diclofenac metabolism. This study illustrates several generalizable design and operational principles for implementing multi-MPS "physiome-on-a-chip" approaches in drug discovery.


Subject(s)
Coculture Techniques/methods , Diclofenac/pharmacokinetics , Lab-On-A-Chip Devices , Liver/metabolism , Animals , Drug Evaluation, Preclinical , Humans , Microchip Analytical Procedures , Models, Biological , Phenotype , Rats
10.
Nat Commun ; 9(1): 364, 2018 01 25.
Article in English | MEDLINE | ID: mdl-29371663

ABSTRACT

Tomato (Solanum lycopersicum) is an established model for studying fruit biology; however, most studies of tomato fruit growth and ripening are based on homogenized pericarp, and do not consider the internal tissues, or the expression signatures of individual cell and tissue types. We present a spatiotemporally resolved transcriptome analysis of tomato fruit ontogeny, using laser microdissection (LM) or hand dissection coupled with RNA-Seq analysis. Regulatory and structural gene networks, including families of transcription factors and hormone synthesis and signaling pathways, are defined across tissue and developmental spectra. The ripening program is revealed as comprising gradients of gene expression, initiating in internal tissues then radiating outward, and basipetally along a latitudinal axis. We also identify spatial variations in the patterns of epigenetic control superimposed on ripening gradients. Functional studies elucidate previously masked regulatory phenomena and relationships, including those associated with fruit quality traits, such as texture, color, aroma, and metabolite profiles.


Subject(s)
Fruit/genetics , Gene Expression Regulation, Developmental , Gene Expression Regulation, Plant , Solanum lycopersicum/genetics , Transcriptome , Fruit/growth & development , Fruit/ultrastructure , Gene Expression Profiling/methods , Gene Regulatory Networks , Solanum lycopersicum/growth & development , Microscopy, Electron, Transmission , Plant Proteins/genetics , Plants, Genetically Modified
11.
Bioinformatics ; 33(15): 2397-2398, 2017 Aug 01.
Article in English | MEDLINE | ID: mdl-28379331

ABSTRACT

SUMMARY: With the development of new high-throughput DNA sequencing technologies and decreasing costs, large gene expression datasets are being generated at an accelerating rate, but can be complex to visualize. New, more interactive and intuitive tools are needed to visualize the spatiotemporal context of expression data and help elucidate gene function. Using tomato fruit as a model, we have developed the Tomato Expression Atlas to facilitate effective data analysis, allowing the simultaneous visualization of groups of genes at a cell/tissue level of resolution within an organ, enhancing hypothesis development and testing in addition to candidate gene identification. This atlas can be adapted to different types of expression data from diverse multicellular species. AVAILABILITY AND IMPLEMENTATION: The Tomato Expression Atlas is available at http://tea.solgenomics.net/ . Source code is available at https://github.com/solgenomics/Tea . CONTACT: jr286@cornell.edu or lam87@cornell.edu. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.


Subject(s)
Databases, Nucleic Acid , Gene Expression Regulation, Plant , Sequence Analysis, RNA/methods , Solanum lycopersicum/genetics , Transcriptome , High-Throughput Nucleotide Sequencing , Organ Specificity
12.
Arthroscopy ; 33(1): 19-25, 2017 Jan.
Article in English | MEDLINE | ID: mdl-27659242

ABSTRACT

PURPOSE: To compare patient-reported outcomes and healing rates after open subpectoral and all-arthroscopic suprapectoral biceps tenodesis without the use of interference screws in patients with more than 2 years of follow-up. METHODS: Patients with at least 2 years of follow-up who underwent open subpectoral biceps tenodesis or all-arthroscopic suprapectoral biceps tenodesis without concomitant rotator cuff repair, labral repair, or Mumford procedure were considered for enrollment in the study. They were evaluated for visual analog scale (VAS), American Shoulder and Elbow Surgeons (ASES) score, and satisfaction with function and biceps contour. Ultrasonography was performed to evaluate the integrity of the tenodesis site and measure biceps muscle diameters on each arm. RESULTS: Forty-nine patients were eligible for our study and of these, 38 were able to participate. Twenty-three patients had open subpectoral biceps tenodesis and 15 received all-arthroscopic suprapectoral biceps tenodesis. The average follow-up time was 4.5 years (range 2-9.1 years). There were no significant differences in anterior shoulder pain VAS, ASES scores, or satisfaction rates. The average anterior shoulder VAS was 0.7 ± 1.1 for the open group and 0.9 ± 1.8 for the arthroscopic group (P = .74). The mean ASES score for the open group was 90.6 ± 11.4 and 91.4 ± 13.9 for the arthroscopic group (P = .69). All patients had an intact tenodesis site on ultrasonography and the ratio of operative to nonoperative biceps diameters was 100.2% ± 12.8% for the open group and 99.1% ± 10.8% for the arthroscopic group (P = .66). There were no infections and no brachial plexus injuries in either group. CONCLUSIONS: Open subpectoral biceps tenodesis and all-arthroscopic suprapectoral biceps tenodesis are both successful surgeries with consistently positive outcomes. Tenodesis can be performed in either location without interference screw fixation with durable, reliable results. LEVEL OF EVIDENCE: Level III, retrospective comparative trial.


Subject(s)
Arm/surgery , Bone Screws , Tendons/surgery , Tenodesis/methods , Arm/diagnostic imaging , Arthroscopy/methods , Female , Humans , Male , Middle Aged , Pain Measurement , Patient Satisfaction , Plastic Surgery Procedures/methods , Retrospective Studies , Shoulder Pain/etiology , Treatment Outcome
13.
Arthroscopy ; 32(9): 1761-3, 2016 09.
Article in English | MEDLINE | ID: mdl-27594327

ABSTRACT

Acellular human dermal matrix allografts are now being used to augment and sometimes replace severely damaged rotator cuff tissue. I have been interested in this important aspect of orthopaedics for 15 years and am pleased to have the opportunity to share my personal reflections of some of the highlights in science and the literature that helped get to the point now where we can expect greater than 80% healing even in these difficult cases of revision after massive failed cuff repair. The field of tissue engineering will certainly be a critical part of our rotator cuff surgical future.


Subject(s)
Allografts , Shoulder , Arthroscopy , Humans , Rotator Cuff Injuries , Surgeons
15.
J Shoulder Elbow Surg ; 25(1): 149-57, 2016 Jan.
Article in English | MEDLINE | ID: mdl-26344873

ABSTRACT

BACKGROUND: The Caspari-Weber (C.W.) tenodesis is a standard miniopen intraosseous technique to fix the long head of the biceps tendon. The suprapectoral intraosseous biceps tenodesis (SPIBiT) is a novel arthroscopic, intraosseous, tendon-sparing alternative using a cortical button. No biomechanical data exist comparing the time-zero performance of the SPIBiT and C.W. constructs. METHODS: Nine pairs of human cadaver shoulders were tested. The SPIBiT used a finger-trap suture pattern holding the tendon inside a humeral tunnel above the pectoralis tendon, anchored with a cortical button on the anterior humerus distal to the bicipital groove. The subpectoral C.W. used a Krackow suture technique. Specimens underwent 500 cycles of uniaxial loading, followed by ultimate failure testing. RESULTS: The SPIBiT was placed in 5 left and 4 right humeri (5 female, 4 male; 59 ± 6 years). The C.W. was initially stiffer (P = .003), whereas the SPIBiT exhibited higher energy dissipation (hysteresis; P = .006). Metrics decreased for both constructs over 500 cycles (P ≤ .050). Constructs failed through suture bunching and tendon tearing within the main suture bundle. The SPIBiT exhibited a novel failure in 2 specimens, with the cortical button pulling distally and suture cutting through cortical bone. Failure occurred at 272.0 ± 114.3 N and 282.3 ± 59.4 N for the SPIBiT and C.W., respectively (P = .766). The C.W. was stiffer (P < .001). CONCLUSION: The SPIBiT is an arthroscopic suprapectoral intraosseous alternative to the C.W. biceps tenodesis, but in light of the novel failure mode, clinical use is not recommended. Future investigations should quantify the impact of construct compliance on healing, and future constructs should avoid suture point loading on thin cortical bone.


Subject(s)
Humerus/surgery , Tendons/surgery , Tenodesis/adverse effects , Tenodesis/methods , Aged , Arm , Biomechanical Phenomena , Cadaver , Female , Humans , Male , Middle Aged , Muscle, Skeletal/surgery , Suture Techniques , Sutures/adverse effects , Tendon Injuries/etiology , Treatment Failure
16.
Sports Med Arthrosc Rev ; 23(3): 130-8, 2015 Sep.
Article in English | MEDLINE | ID: mdl-26225572

ABSTRACT

The successful treatment of symptomatic chronic, massive irreparable rotator cuff tears remains a difficult problem for many shoulder surgeons. Multiple procedures have been attempted to address this problem including latissimus dorsi transfer, arthroscopic shoulder debridement, and reverse total shoulder arthroplasty. Not every patient is a candidate for the above procedures and those that do undergo one of the above procedures has no guarantee of experiencing clinical improvement. Therefore, many shoulder surgeons have looked toward additional methods to manage the chronic, massive irreparable rotator cuff tear. Acellular human dermal allograft is a "graft" material that we have been using to reliably and successfully restore function to patients with these otherwise irreparable rotator cuff tears.


Subject(s)
Orthopedic Procedures/methods , Rotator Cuff Injuries , Shoulder Joint/surgery , Arthroplasty, Replacement , Arthroscopy/methods , Humans , Rotator Cuff/surgery
17.
Arthrosc Tech ; 4(1): e47-50, 2015 Feb.
Article in English | MEDLINE | ID: mdl-25973373

ABSTRACT

Restoration of glenoid bony integrity is critical to minimizing the risk of recurrence and re-creating normal kinematics in the setting of anterior glenohumeral instability. We present an arthroscopic suture anchor-based technique for treating large bony Bankart fractures in which the fragment is secured to the intact glenoid using mattress sutures placed through the bony fragment and augmented with soft-tissue repair proximal and distal to the bony lesion. This straightforward technique has led to excellent fragment reduction and good outcomes in our experience.

18.
Clin Biomech (Bristol, Avon) ; 30(2): 188-94, 2015 Feb.
Article in English | MEDLINE | ID: mdl-25533271

ABSTRACT

BACKGROUND: The interference screw technique is commonly used in tenodesis of the long head of the biceps for its well-documented robust fixation strength. Some complications may occur after tenodesis with interference screw such as persistent pain, bone fracture and cyst formation. A new technique using a small "soft anchor" has been proposed to avoid the risk of occurrence of the above-mentioned complications associated with the use of the interference screw. However, the proposed technique must provide adequate fixation strength. This study investigated the mechanical performance of the new technique and compared it with interference screw fixation. METHODS: Fourteen human humeri and proximal biceps were tested after tenodesis using the two techniques. The fixation constructs were cycled 500 times between 20N and 100N at 1Hz to simulate some level of post-operative physical activity. Then, a tensile test to failure was performed to determine the strength of the two tenodesis constructs. FINDINGS: The ultimate strength was 238N (SD 96N) and 172N (SD 58N) for the "soft anchor" and the interference screw, respectively (P=0.14). In two out of seven repetitions in both groups, failure occurred at low load level due to inaccuracies in performing tenodesis. Considering these cases as outliers, the strength values increased up to 290N (SD 40N) and 202N (SD 32N) for the "soft anchor" and the interference screw, respectively (P=0.02). INTERPRETATION: The "soft anchor" technique provides a fixation strength comparable with the interference screw, but without using a screw. It could be considered as an alternative for suprapectoral biceps tenodesis.


Subject(s)
Suture Anchors , Tenodesis/methods , Aged , Aged, 80 and over , Arm/surgery , Biomechanical Phenomena , Bone Screws , Cadaver , Humans , Middle Aged , Muscle, Skeletal/surgery
20.
Arthroscopy ; 29(10): 1601-2, 2013 Oct.
Article in English | MEDLINE | ID: mdl-24075609
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