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Ulnar collateral ligament (UCL) tears have moved from a career-ending injury to one in which success is almost expected from reconstruction. In reality, however, success from a UCL reconstruction is not guaranteed. As we have attempted to assess the true success rate of UCL reconstructions, we have also learned the difficulties of this assessment. Rates of return to sport after UCL reconstruction vary by level of play, the primary or revision status of the repair, along with the specific surgical techniques performed, the chronicity of the tear, the rehabilitation protocols associated with the surgery, and more. Return to sport is difficult to assess, as high school, collegiate, and even professional careers can be variable and there are no standard definitions of "returning to play." These variables also affect our assessments of performance after UCL reconstruction. Decisions for UCL reconstructions and appropriate counseling of patients regarding the likelihood of success currently remain an individual process.
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Ligamento Colateral Ulnar , Volta ao Esporte , Reconstrução do Ligamento Colateral Ulnar , Humanos , Ligamento Colateral Ulnar/cirurgia , Ligamento Colateral Ulnar/lesõesRESUMO
The reporting and analysis of patient-reported outcome measures have come a long way. Since the concept of the minimally clinically important difference was first introduced in 1989, threshold scores have grown to include substantial clinical benefit and patient acceptable symptomatic state (PASS). The initial motivation for developing these thresholds was rooted in separating clinical significance from statistical. These thresholds provide insight into the relationship between scores on patient-reported outcome measures (PROM) and patient-reported improvement and satisfaction. It follows that in order to evaluate PROM scores, the best method for deriving the threshold typically uses an anchor-based methodology, i.e., "ask the patient." Specifically, patients are asked how much change they've experienced and whether they consider their current state to be satisfactory. The responses to these questions are compared with the scores on PROMs to find outcome thresholds that best separate patients who reported no improvement from those who reported minimal improvement, substantial improvement, and satisfaction with their current state of health (PASS). The PASS is of particular importance as it speaks to what arguably matters most to patients-a satisfactory state of health. Finally, viewing the PASS from the perspective of variation from study to study rather than as a uniform classifier is needed to make use of the growing number of papers reporting these thresholds. Examining differences in PASS values across papers can provide insight into how well PROM scores reflect patient satisfaction in different settings.
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Artroplastia do Joelho , Satisfação do Paciente , Humanos , Medidas de Resultados Relatados pelo Paciente , Diferença Mínima Clinicamente Importante , Resultado do TratamentoRESUMO
PURPOSE: To examine the effect of various biologic adjuvants on the polarization of macrophages in an in vitro model for rotator cuff tears. METHODS: Tissue was harvested from 6 patients undergoing arthroscopic rotator cuff repair. An in vitro model of the supraspinatus and subacromial bursa was created and treated with control, platelet-rich plasma (PRP), autologous activated serum (AAS), or a combination of PRP+AAS. The effect of treatment on macrophage polarization between M1 proinflammatory macrophages or M2 anti-inflammatory macrophages was measured using gene expression, protein expression, flow cytometry, and nitric oxide production. RESULTS: Tendon and bursa treated with PRP, AAS, and PRP+AAS significantly decreased the gene expression of M1 markers interleukin (IL)-12 and tumor necrosis factor-alpha while significantly increasing the expression of M2 markers arginase, IL-10, and transforming growth factor-ß (P < .05) compared with treatment with control. Enzyme-linked immunosorbent assay analysis of protein production demonstrated that, compared with control, coculture treated with PRP, AAS, and PRP+AAS significantly decreased markers of M1-macrophages (IL-6, IL-12, and tumor necrosis factor-alpha) while significantly increasing the expression of markers of M2-macrophages (arginase, IL-10, and transforming growth factor-beta) (P < .05). Flow cytometry analysis of surface markers demonstrated that compared with control, tendon and bursa treated with PRP, AAS, and PRP+AAS significantly decreased markers of M1-macrophages (CD80, CD86, CD64, CD16) while significantly increasing the expression of markers of M2-macrophages (CD163 and CD206) (P < .05). Treatment of the coculture with PRP, AAS, and PRP+AAS consistently demonstrated a decrease in nitric oxide production (P < .05) compared with control. AAS and PRP+AAS demonstrated an increased macrophage shift to M2 compared with PRP alone, whereas there was not as uniform of a shift when comparing PRP+AAS with AAS alone. CONCLUSIONS: In an in vitro model of rotator cuff tears, the treatment of supraspinatus tendon and subacromial bursa with PRP, AAS, and PRP+AAS demonstrated an increase in markers of anti-inflammatory M2-macrophages and a concomitant decrease in markers of proinflammatory M1-macrophages. AAS and PRP+AAS contributed to a large shift to macrophage polarization to the anti-inflammatory M2 compared with PRP. CLINICAL RELEVANCE: The mechanism of biologic adjuvant effects on the rotator cuff remains poorly understood. This study suggests that they may contribute to polarization of macrophages for their proinflammatory (M1) state to the anti-inflammatory (M2) state.
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PURPOSE: To quantify cellular senescence in supraspinatus tendon and subacromial bursa of humans with rotator cuff tears and to investigate the in vitro efficacy of the senolytic dasatinib + quercetin (D+Q) to eliminate senescent cells and alter tenogenic differentiation. METHODS: Tissue was harvested from 41 patients (mean age, 62 years) undergoing arthroscopic rotator cuff repairs. In part 1 (n = 35), senescence was quantified using immunohistochemistry and gene expression for senescent cell markers (p16 and p21) and the senescence-associated secretory phenotype (SASP) (interleukin [IL] 6, IL-8, matrix metalloproteinase [MMP] 3, monocyte chemoattractant protein [MCP] 1). Senescence was compared between patients <60 and ≥60 years old. In part 2 (n = 6) , an in vitro model of rotator cuff tears was treated with D+Q or control. D+Q, a chemotherapeutic and plant flavanol, respectively, kill senescent cells. Gene expression analysis assessed the ability of D+Q to kill senescent cells and alter markers of tenogenic differentiation. RESULTS: Part 1 revealed an age-dependent significant increase in the relative expression of p21, IL-6, and IL-8 in tendon and p21, p16, IL-6, IL-8, and MMP-3 in bursa (P < .05). A significant increase was seen in immunohistochemical staining of bursa p21 (P = .028). In part 2, D+Q significantly decreased expression of p21, IL-6, and IL-8 in tendon and p21 and IL-8 in bursa (P < .05). Enzyme-linked immunosorbent assay analysis showed decreased release of the SASP (IL-6, MMP-3, MCP-1; P = .002, P = .024, P < .001, respectively). Tendon (P = .022) and bursa (P = .027) treated with D+Q increased the expression of COL1A1. CONCLUSIONS: While there was an age-dependent increase in markers of cellular senescence, this relationship was not consistently seen across all markers and tissues. Dasatinib + quercetin had moderate efficacy in decreasing senescence in these tissues and increasing COL1A1 expression. CLINICAL RELEVANCE: This study reveals that cellular senescence may be a therapeutic target to alter the biological aging of rotator cuffs and identifies D+Q as a potential therapy.
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Lesões do Manguito Rotador , Humanos , Pessoa de Meia-Idade , Lesões do Manguito Rotador/tratamento farmacológico , Lesões do Manguito Rotador/cirurgia , Dasatinibe/farmacologia , Dasatinibe/uso terapêutico , Quercetina/farmacologia , Quercetina/uso terapêutico , Metaloproteinase 3 da Matriz/genética , Interleucina-6/metabolismo , Interleucina-8 , Senescência CelularRESUMO
BACKGROUND: Elliptical shape humeral head prostheses have been recently proposed to reflect a more anatomic shoulder replacement. However, its effect on obligate glenohumeral translation during axial rotation compared to a standard spherical head is still not well understood. The purpose of the study was to compare obligate humeral translation during axial rotation using spherical and elliptical shaped humeral head prostheses. It was hypothesized that the spherical head design would show significantly more obligate translation when compared to the elliptical design. METHODS: Six fresh-frozen cadaveric shoulders were utilized for biomechanical testing of internal (IR) and external (ER) rotation at various levels of abduction (0°, 30°, 45°, 60°) with lines of pull along each of the rotator cuff muscles. Each specimen underwent the following three conditions: (1) native; total shoulder arthroplasty (TSA) using (2) an elliptical and (3) spherical humeral head implant. Obligate translation during IR and ER was quantified using a 3-dimensional digitizer. The radius of curvature of the superoinferior and anteroposterior dimensions of the implants was calculated across each condition. RESULTS: Posterior and inferior translation as well as compound motion of spherical and elliptical heads during ER was similar at all abduction angles (P > 0.05, respectively). Compared to the native humeral head, both implants demonstrated significantly decreased posterior translation at 45° (elliptical: P = 0.003; spherical: P = 0.004) and 60° of abduction (elliptical: P < 0.001; spherical: P < 0.001). During internal rotation at 0° abduction, the spherical head showed significantly more compound motion (P = 0.042) compared to the elliptical head. The spherical implant also demonstrated increased anterior translation and compound motion during internal rotation at 60° abduction (P < 0.001) compared to the resting state. This difference was not significant for the native or elliptical head design at this angle (P > 0.05). CONCLUSION: In the setting of TSA, elliptical and spherical head implants showed similar obligate translation and overall compound motion during axial rotation. A gained understanding of the consequences of implant head shape in TSA may guide future surgical implant choice for better recreation of native shoulder kinematics and potentially improved patient outcomes. LEVEL OF EVIDENCE: Controlled Laboratory Study.
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Artroplastia do Ombro , Artroplastia de Substituição , Bursite , Humanos , Rotação , Extremidade Superior , Cabeça do Úmero/cirurgiaRESUMO
Optimal treatment of irreparable rotator cuff tears is still debated. Proponents of the superior capsule reconstruction (SCR) have previously used fascia lata autograft and acellular dermal allograft. Interest is growing in using fascia lata allograft as a new graft material. Well-designed biomechanical studies are important to understand the mechanical properties of the superior capsular tissue and fascia lata allograft. Recent biomechanical research shows that fascia lata allograft has similar initial stiffness (over the first 2 mm) and ultimate load compared to the native superior capsule. That said, ultimate load is the load at which a construct fails, whereas the yield point is the load on the stress-strain curve at which a material transitions from elastic to plastic deformation. In the shoulder where the SCR, for example, is going to be repetitively loaded, it is potentially more meaningful to talk about the yield point in order to stay within the elastic range. Using this framework, the yield point for fascia lata allograft is approximately one third the yield point of native capsular tissue. Additionally, "initial" stiffness is not the entire story. At greater loads, fascia lata allograft has higher displacement compared to native tissue. Of importance, fascia lata allograft failed by sutures slowly cutting through the allograft tissue; this may represent a limitation of the construct that could be addressed using stitch configurations resistant to cut through. Fascia lata allograft is a promising solution for SCR. Biomechanical studies require nuanced interpretation, and most of all, do not evaluate clinical healing.
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Lesões do Manguito Rotador , Articulação do Ombro , Humanos , Lesões do Manguito Rotador/cirurgia , Ombro , Fascia Lata/transplante , Articulação do Ombro/cirurgia , Amplitude de Movimento Articular , AloenxertosRESUMO
PURPOSE: To evaluate the effect of an irreparable posterosuperior rotator cuff tear (PSRCT) on glenohumeral joint loads and to quantify improvement after superior capsular reconstruction (SCR) using an acellular dermal allograft. METHODS: Ten fresh-frozen cadaveric shoulders were tested using a validated dynamic shoulder simulator. A pressure mapping sensor was placed between the humeral head and glenoid surface. Each specimen underwent the following conditions: (1) native, (2) irreparable PSRCT, and (3) SCR using a 3-mm-thick acellular dermal allograft. Glenohumeral abduction angle (gAA) and superior humeral head migration (SM) were measured using 3-dimensional motion-tracking software. Cumulative deltoid force (cDF) and glenohumeral contact mechanics, including glenohumeral contact area and glenohumeral contact pressure (gCP), were assessed at rest, 15°, 30°, 45°, and maximum angle of glenohumeral abduction. RESULTS: The PSRCT resulted in a significant decrease of gAA along with an increase in SM, cDF, and gCP (P < .001, respectively). SCR did not restore native gAA (P < .001); however, SM was significantly reduced (P < .001). Further, SCR significantly reduced deltoid forces at 30° (P = .007) and 45° of abduction (P = .007) when compared with the PSRCT. SCR did not restore native cDF at 30° (P = .015), 45° (P < .001), and maximum angle (P < .001) of glenohumeral abduction. Compared with the PSRCT, SCR resulted in a significant decrease of gCP at 15° (P = .008), 30° (P = .002), and 45° (P = .006). However, SCR did not completely restore native gCP at 45° (P = .038) and maximum abduction angle (P = .014). CONCLUSIONS: In this dynamic shoulder model, SCR only partially restored native glenohumeral joint loads. However, SCR significantly decreased glenohumeral contact pressure, cumulative deltoid forces, and superior migration, while increasing abduction motion, when compared with the posterosuperior rotator cuff tear. CLINICAL RELEVANCE: These observations raise concerns regarding the true joint-preserving potential of SCR for an irreparable posterosuperior rotator cuff tear, along with its ability to delay progression of cuff tear arthropathy and eventual conversion to reverse shoulder arthroplasty.
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Lesões do Manguito Rotador , Articulação do Ombro , Humanos , Ombro , Articulação do Ombro/cirurgia , Lesões do Manguito Rotador/cirurgia , Fenômenos Biomecânicos , Escápula , Cadáver , Amplitude de Movimento ArticularRESUMO
BACKGROUND: Cutibacterium acnes is the most common microbe implicated in periprosthetic infection in shoulder arthroplasty. We present an update of a previous pilot study in which we demonstrated the persistence of C acnes on the skin and contamination of the scalpel used for the initial skin incision despite a robust presurgical skin preparation protocol. METHODS: We collected a consecutive case series of patients undergoing primary or revision anatomic or reverse total shoulder arthroplasty performed by a single fellowship-trained surgeon at a tertiary referral hospital from November 2019 to December 2022. The scalpel blade used for the initial skin incision in each patient was swabbed, with cultures being held for 21 days according to a C acnes-specific protocol. Demographic data, medical comorbidities, surgical information, culture results, and infections were documented. RESULTS: We identified 100 patients (51 men and 49 women) who met the inclusion criteria (mean age, 66.91 years; age range, 44-93 years). Cultures returned positive findings for C acnes in 12 patients (12%), 11 of whom were men (odds ratio, 13.2; 95% confidence interval, 1.73-194.87). No association was found between positive culture findings and age, body mass index, medical comorbidities, or procedure type. No postoperative infections occurred in this patient cohort, and the patients will continue to be monitored for the development of infection. CONCLUSION: Despite stringent presurgical preparation and scrub protocols, a significant portion of patients undergoing shoulder arthroplasty have C acnes in culturable quantities on their skin at the time of incision. C acnes contamination is much more common in male patients. These findings should be taken into consideration regarding preventive measures such as discarding the initial scalpel and avoiding unnecessary dermal contact during the procedure.
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Artroplastia do Ombro , Infecções por Bactérias Gram-Positivas , Articulação do Ombro , Ferida Cirúrgica , Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Articulação do Ombro/cirurgia , Projetos Piloto , Infecções por Bactérias Gram-Positivas/microbiologia , Pele/microbiologia , Propionibacterium acnesRESUMO
BACKGROUND: Subscapularis failure is a troublesome complication following anatomic total shoulder arthroplasty (aTSA). Commonly discarded during aTSA, the long head of the biceps tendon (LHBT) may offer an efficient and cheap autograft for the augmentation of the subscapularis repair during aTSA. The purpose of this study was to biomechanically compare a standard subscapularis peel repair to 2 methods of subscapularis peel repair augmented with LHBT. METHODS: 18 human cadaveric shoulders (61 ± 9 years of age) were used in this study. Shoulders were randomly assigned to biomechanically compare subscapularis peel repair with (1) traditional single-row repair, (2) single row with horizontal LHBT augmentation, or (3) single row with V-shaped LHBT augmentation. Shoulders underwent biomechanical testing on a servohydraulic testing system to compare cyclic displacement, load to failure, and stiffness. RESULTS: There were no significant differences in the cyclic displacement between the 3 techniques in the superior, middle, or inferior portion of the subscapularis repair (P > .05). The horizontal (436.7 ± 113.3 N; P = .011) and V-shape (563.3 ± 101.0 N; P < .001) repair demonstrated significantly greater load to failure compared with traditional repair (344.4 ± 82.4 N). The V-shape repair had significantly greater load to failure compared to the horizontal repair (P < .001). The horizontal (61.6 ± 8.4 N/mm; P < .001) and the V-shape (62.8 ± 6.1; P < .001) repairs demonstrated significantly greater stiffness compared to the traditional repair (47.6 ± 6.2 N). There was no significant difference in the stiffness of the horizontal and V-shape repairs (P = .770). CONCLUSIONS: Subscapularis peel repair augmentation with LHBT autograft following aTSA confers greater time zero load to failure and stiffness when compared to a standard subscapularis peel repair.
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Artroplastia do Ombro , Articulação do Ombro , Humanos , Artroplastia do Ombro/métodos , Fenômenos Biomecânicos , Cadáver , Manguito Rotador/cirurgia , Articulação do Ombro/cirurgia , Técnicas de Sutura , Tendões/cirurgiaRESUMO
INTRODUCTION: Elliptical-shaped humeral head prostheses have recently been proposed to reflect a more anatomic shoulder replacement. However, its subsequent effect on micro-motion of the glenoid component is still not understood. MATERIALS AND METHODS: Six fresh-frozen, cadaveric shoulders (mean age: 62.7 ± 9.2 years) were used for the study. Each specimen underwent total shoulder arthroplasty using an anatomic stemless implant. At 15°, 30°, 45° and 60° of glenohumeral abduction, 50° of internal and external rotations in the axial plane were alternatingly applied to the humerus with both an elliptical and spherical humeral head design. Glenohumeral translation was assessed by means of a 3-dimensional digitizer. Micro-motion of the glenoid component was evaluated using four high-resolution differential variable reluctance transducer strain gauges, placed at the anterior, posterior, superior, and inferior aspect of the glenoid component. RESULTS: The elliptical head design showed significantly more micro-motion in total and at the superior aspect of glenoid component during external rotation at 15° (total: P = 0.004; superior: P = 0.004) and 30° (total: P = 0.045; superior: P = 0.033) of abduction when compared to the spherical design. However, during internal rotation, elliptical and spherical heads showed similar amounts of micro-motion at the glenoid component at all tested abduction angles. When looking at glenohumeral translation, elliptical and spherical heads showed similar anteroposterior and superoinferior translation as well as compound motion during external rotation at all tested abduction angles. During internal rotation, the elliptical design resulted in significantly more anteroposterior translation and compound motion at all abduction angles when compared to the spherical design (P < 0.05). CONCLUSION: In the setting of total shoulder arthroplasty, the elliptical head design demonstrated greater glenohumeral translation and micro-motion at the glenoid component during axial rotation when compared to the spherical design, potentially increasing the risk for glenoid loosening in the long term. LEVEL OF EVIDENCE: Controlled Laboratory Study.
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Artroplastia do Ombro , Articulação do Ombro , Humanos , Pessoa de Meia-Idade , Idoso , Articulação do Ombro/cirurgia , Fenômenos Biomecânicos , Amplitude de Movimento Articular , Cadáver , Cabeça do Úmero/cirurgiaRESUMO
PURPOSE/AIM: The purpose of this study is to identify a cell population within the murine subcromial bursal-derived cells with characteristics compatible to an accepted mesenchymal stem cell description given by the International Society for Cellular Therapy (ISCT). MATERIALS AND METHODS: Murine subacromial bursa was harvested using microsurgical technique. Subacromial bursal-derived cells were classified through colony-forming units, microscopic morphology, fluorescent-activated cell sorting, and differentiation into chondrogenic, adipogenic, and osteogenic lineages. RESULTS: Subacromial bursal samples exhibited cell growth out of the tissue for an average of 115 ± 29 colony-forming units per 1 mL of complete media. Subacromial bursal-derived cells exhibited a long, spindle-shaped, fibroblast-like morphology. Subacromial bursal-derived cells positively expressed mesenchymal stem cell markers CD73, CD90, and CD105, and negatively expressed mesenchymal stem cell markers CD31 and CD45. Subacromial bursal-derived cells, examined by Image J analysis and quantitative gene expression, were found to differentiate into chondrogenic, adipogenic, and osteogenic lineages. CONCLUSIONS: This study demonstrated the feasibility of harvesting murine subacromial bursal tissue and identified a cell population within the subacromial bursa with characteristics compatible to an accepted mesenchymal stem cell description. The results of this study suggest that the mouse subacromial bursal-derived cell population harbors mesenchymal stem cells. Murine subacromial bursal tissue is a potential source for obtaining cells with mesenchymal stem cell characteristics for future utilization in orthopedic research to look into treatment of rotator cuff pathology.
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Células-Tronco Mesenquimais , Lesões do Manguito Rotador , Articulação do Ombro , Animais , Bolsa Sinovial/patologia , Diferenciação Celular , Camundongos , Manguito Rotador/patologia , Lesões do Manguito Rotador/patologiaRESUMO
BACKGROUND: There exists a vast number of surgical treatment options for acromioclavicular (AC) joint injuries, and the current literature has yet to determine an equivocally superior treatment. AC joint repair has a long history and dates back to the beginning of the twentieth century. MAIN BODY: Since then, over 150 different techniques have been described, covering open and closed techniques. Low grade injuries such as Type I-II according to the modified Rockwood classification should be treated conservatively, while high-grade injuries (types IV-VI) may be indicated for operative treatment. However, controversy exists if operative treatment is superior to nonoperative treatment, especially in grade III injuries, as functional impairment due to scapular dyskinesia or chronic pain remains concerning following non-operative treatment. Patients with a stable AC joint without overriding of the clavicle and without significant scapular dysfunction (Type IIIA) may benefit from non-interventional approaches, in contrast to patients with overriding of the clavicle and therapy-resistant scapular dysfunction (Type IIIB). If these patients are considered non-responders to a conservative approach, an anatomic AC joint reconstruction using a hybrid technique should be considered. In chronic AC joint injuries, surgery is indicated after failed nonoperative treatment of 3 to 6 months. Anatomic AC joint reconstruction techniques along with biologic augmentation (e.g. Hybrid techniques, suture fixation) should be considered for chronic high-grade instabilities, accounting for the lack of intrinsic healing and scar-forming potential of the ligamentous tissue in the chronic setting. However, complication and clinical failure rates remain high, which may be a result of technical failures or persistent horizontal and rotational instability. CONCLUSION: Future research should focus on addressing horizontal and rotational instability, to restore native physiological and biomechanical properties of the AC joint.
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Articulação Acromioclavicular , Luxações Articulares , Instabilidade Articular , Humanos , Articulação Acromioclavicular/diagnóstico por imagem , Articulação Acromioclavicular/cirurgia , Articulação Acromioclavicular/lesões , Instabilidade Articular/cirurgia , Instabilidade Articular/etiologia , Artroplastia/métodos , Clavícula/cirurgia , Suturas/efeitos adversos , Luxações Articulares/cirurgia , Luxações Articulares/complicaçõesRESUMO
PURPOSE: To build upon previous literature to identify a complete analysis of cellular contents of subacromial bursal tissue as well as the matrix surrounding the rotator cuff. METHODS: Samples of subacromial bursal tissue and surrounding matrix milieu from above the rotator cuff tendon and above the rotator cuff muscle bellies were obtained from 10 patients undergoing arthroscopic rotator cuff repair. Samples were analyzed using fluorescent-activated cell sorting and histologic analysis with staining protocols (Oil Red O, Alcian Blue, and Picro-Sirius Red), for identification of matrix components, including fat, proteoglycans, and collagen. RESULTS: Progenitor cells and fibroblast-type cells were present in significant amounts in subacromial bursal tissue in both tissues obtained from over the tendinous and muscle belly portions. Markers for neural tissue, myeloid cells, and megakaryocytes also were present to a lesser extent. There were prominent amounts of fat and proteoglycans present in the matrix, based on ImageJ analysis of stained histologic slides. CONCLUSIONS: The subacromial bursal tissue and surrounding matrix of patients undergoing rotator cuff repair contains progenitor cells in significant concentrations both over the tendon and muscle belly of the rotator cuff. CLINICAL RELEVANCE: This presence of progenitor cells, in particular, in the subacromial bursal tissue provides a potential basis for future applications of augmentation purposes in rotator cuff healing, and calls into question the practice of routine bursectomy. As the potential role of bursal tissue contents in growth and regeneration in the setting of rotator cuff healing is more well understood, maintaining this tissue may become more relevant. Concentration of these cellular components for use in autologous re-implantation is also an avenue of interest.
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Lesões do Manguito Rotador , Manguito Rotador , Bolsa Sinovial/patologia , Bolsa Sinovial/cirurgia , Humanos , Manguito Rotador/cirurgia , Lesões do Manguito Rotador/patologia , Lesões do Manguito Rotador/cirurgia , Células-Tronco , Tendões/cirurgiaRESUMO
PURPOSE: To perform a quantitative anatomic evaluation of the deltoid and trapezius footprints in relation to the lateral clavicle and acromioclavicular (AC) joint capsule to assist in surgical technique of AC joint reconstructions. METHODS: Fourteen fresh-frozen human cadaveric shoulders from 9 donors were analyzed. Meticulous dissection of the deltoid origin and trapezius insertions to the clavicle and AC joint was performed. Footprints were reconstructed using a MicroScribe digitizer. The inferior extension of the deltoid origin beneath the lateral clavicle and the footprints of the deltoid and trapezius onto the acromioclavicular ligamentous complex (ACLC) were quantified. Reproducibility was assessed by redigitizing 5 shoulders in a blinded and random fashion. RESULTS: The anterior deltoid fibers extended on average 4.0 ± 1.6 mm inferiorly with respect to the anteroinferior clavicular ridge and attached to 90.9 ± 7.3% of the anterior ACLC. The trapezius inserted onto the posterior and superior ACLC, covering 15.3 ± 3.4% of the anterior-posterior width of the superior capsule. The deltopectoral interval was 6 cm, or 37% the length of the clavicle from the distal end of the clavicle. CONCLUSIONS: The deltoid has superior, anterior, and not as well described, inferior attachments to the lateral clavicle. Furthermore, the deltoid and trapezius muscles have intimate attachments to the AC joint capsule, particularly the trapezius to the posterior and posterosuperior capsule. Lastly, the deltoid origin attaches to the lateral 6 cm of the clavicle. CLINICAL RELEVANCE: Subperiosteal elevation of the deltoid off the lateral clavicle starting superiorly, anteriorly, and lastly inferiorly will reduce deltoid muscle injury and improve visibility of the coracoid process during reconstruction. Furthermore, knowledge of the attachments of the deltoid and trapezius to the ACLC may help limit iatrogenic injury to these dynamic stabilizers.
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Articulação Acromioclavicular , Artroplastia de Substituição , Músculos Superficiais do Dorso , Articulação Acromioclavicular/cirurgia , Fenômenos Biomecânicos/fisiologia , Cadáver , Clavícula/cirurgia , Humanos , Ligamentos Articulares/cirurgia , Reprodutibilidade dos Testes , Músculos Superficiais do Dorso/cirurgiaRESUMO
PURPOSE: The purpose was to evaluate the response of human ligamentocytes and osteoblasts after biological augmentation with thrombin, concentrated bone marrow aspirate (cBMA), or platelet-rich plasma (PRP) on two different types of nonresorbable flat braided suture used for ligament bracing. METHODS: Uncoated (U) and collagen-coated (C) flat braided suture material was augmented with either thrombin (T), cBMA (B), PRP (P), or a combination of these three (A), while platelet-poor plasma was used as a source for fibrin (F) in each assay. Previously cultured ligamentocytes and osteoblasts were added with a defined density and assayed after the required time period for adhesion, proliferation, and alkaline phosphatase activity. RESULTS: Biological augmentation of uncoated [(UFT, UFBT, UFA; P < .001), (UFPT; P = .017)] and collagen-coated suture (CFT, CFPT, CFBT, CFA; P < .001) led to a significantly higher ligamentocyte adhesion. Significantly higher adhesion was also observed for osteoblasts (UFT, UFPT, UFBT, UFA; P < .001; CFT, CFPT, CFBT, CFA; P < .001). Similarly, ligamentocyte proliferation was significantly higher [(UFT, UFPT, UFA; P = .009), (UFBT; P = .001), (CFT; P = .009), (CFBT; P = .001), and (CFA; P = .01)]. Osteoblasts showed significantly higher proliferation as well [(UFT, UFPT, UFA; P = .002), (UFBT; P = .001); (CFT: P = .003), and (CFPT, CFBT, CFA; P = .001)]. Augmentation with thrombin, PRP, and BMA for uncoated (UFT; P = .006, UFPT; P = .035, UFBT; P = .001) and BMA for coated suture (CFBT; P = .027) led to significantly higher alkaline phosphatase activity. CONCLUSION: Biological enhancement of suture used for ligament bracing significantly increased ligamentocyte and osteoblast adhesion and proliferation, as well as alkaline phosphatase activity of osteoblasts in an in vitro model. After biological augmentation, cellular adhesion, proliferation, and alkaline phosphatase activity changed up to 1,077%, 190%, and 78%, respectively. Furthermore, no overall superiority between uncoated or collagen-coated suture material was observed for cellular adhesion, proliferation, or alkaline phosphatase activity. CLINICAL RELEVANCE: This study provides in vitro data on a new treatment concept of biologic augmentation for acute ligamentous lesions treated with ligament bracing that has not been widely described. This concept may improve the healing of injured ligaments, in addition to providing immediate biomechanical stabilization.
Assuntos
Osteoblastos , Plasma Rico em Plaquetas , Adesão Celular , Proliferação de Células , Humanos , Ligamentos , Osteoblastos/fisiologia , SuturasRESUMO
PURPOSE: To evaluate the effect of an isolated full-thickness supraspinatus (SSP) tear on glenohumeral kinematics and contact mechanics, as well as to quantify improvement following rotator cuff repair (RCR). METHODS: Ten fresh-frozen cadaveric shoulders (mean age: 63.1 ± 4.6 years) were tested using a dynamic shoulder simulator. A pressure-mapping sensor was placed between the humeral head and the glenoid. Each specimen underwent the following three conditions: 1) native, 2) isolated full-thickness SSP tear, and 3) RCR. Maximum abduction angle (MAA) and superior humeral head migration (SHM) were measured using 3D motion tracking software. Cumulative deltoid force (CDF) and glenohumeral contact mechanics, including contact area (GCA) and contact pressure (GCP), were assessed at the resting position, as well as at 15°, 30°, 45°, and 60° of glenohumeral abduction. RESULTS: Compared to native, the SSP tear resulted in a significant decrease in MAA (Δ-8.3°; P < .001) along with a SHM of 6.4 ± 3.8 mm, while significantly increasing CDF (Δ20.5 N; P = .008), GCP (Δ63.1 kPa; P < .001), and peak GCP (Δ278.6 kPa; P < .001), as well as decreasing GCA (Δ-45.8 mm2; P < .001) at each degree of abduction. RCR reduced SHM to 1.2 ± 2.5 mm, while restoring native MAA, CDF (Δ1.8 N), GCA (Δ4.5 mm2), GCP (Δ-4.5 kPa) and peak GCP (Δ19.9 kPa) at each degree of abduction (P > .999, respectively). CONCLUSION: In a dynamic biomechanical cadaveric model, increased glenohumeral joint loads due to a full-thickness SSP tear can be reversed with RCR. More specifically, RCR restored native glenohumeral contact area and contact pressure, while preventing superior humeral head migration and decreasing compensatory deltoid forces. CLINICAL RELEVANCE: These time 0 observations indicate that undergoing rotator cuff repair may prevent the development of degenerative changes by significantly reducing glenohumeral joint loads and ensuring sufficiently stable joint kinematics.
Assuntos
Bursite , Lacerações , Lesões do Manguito Rotador , Articulação do Ombro , Idoso , Fenômenos Biomecânicos , Cadáver , Humanos , Pessoa de Meia-Idade , Amplitude de Movimento Articular , Manguito Rotador/cirurgia , Lesões do Manguito Rotador/cirurgia , Ruptura , Articulação do Ombro/cirurgiaRESUMO
PURPOSE: To investigate the effect of bursal acromial reconstruction (BAR) using an acellular dermal allograft on glenohumeral joint kinematics including maximum abduction angle, glenohumeral superior translation, cumulative deltoid force, and subacromial contact pressure. METHODS: In this dynamic biomechanical cadaveric shoulder study, 8 fresh-frozen cadaveric shoulders (age 53.4 ± 14.2 years, mean ± standard deviation) were tested using a dynamic shoulder testing system. Maximum abduction angle (MAA), glenohumeral superior translation (ghST), maximum cumulative deltoid force (cDF), and subacromial peak contact pressure (sCP) were compared across 3 conditions: (1) intact shoulder; (2) massive retracted irreparable posterosuperior rotator cuff tear (psRCT) according to Patte III; and (3) BAR. Additionally, humeral head containment was measured using contact pressure. RESULTS: Compared with the simulated psRCT, BAR significantly increased mean MAA and significantly decreased ghST (P < .001, respectively) and cDF (P = .017) Additionally, BAR was found to significantly decrease sCP compared with psRCT (P = .024). CONCLUSION: In a dynamic biomechanical cadaveric shoulder simulator, resurfacing the undersurface of the acromion using the BAR technique leads to significantly improved ghST, MAA, cDF, and sCP compared with the irreparable rotator cuff tear. CLINICAL RELEVANCE: With the BAR technique, native humeral containment may be restored, which can potentially delay progressive subacromial and glenoidal abrasive wear and improve overall shoulder function. As such, the proposed BAR technique can be considered as a technically feasible and potentially cost- and timesaving procedure, as no bone anchors are needed, glenoidal or humeral side graft ruptures can be avoided, and postoperative rehabilitation can be started immediately. However, future clinical studies are needed.
Assuntos
Lesões do Manguito Rotador , Articulação do Ombro , Acrômio/cirurgia , Adulto , Idoso , Aloenxertos , Fenômenos Biomecânicos , Cadáver , Humanos , Cabeça do Úmero , Pessoa de Meia-Idade , Amplitude de Movimento Articular , Lesões do Manguito Rotador/cirurgia , Articulação do Ombro/cirurgiaRESUMO
PURPOSE: Despite their clinical importance in maintaining the stability of the pinch mechanism, injuries of the radial collateral ligament (RCL) of the index finger may be underrecognized and underreported. The purpose of this biomechanical study was to compare the repair of index finger RCL tears with either a standard suture anchor or suture tape augmentation. METHODS: The index fingers from 24 fresh-frozen human cadavers underwent repair of torn RCLs using either a standard suture anchor or suture tape augmentation. Following the repairs, the initial displacement of the repair with a 3-N ulnar deviating load was evaluated. Next, the change in displacement (cyclic deformation) of the repair after 1,000 cycles of 3 N of ulnar deviating force was calculated (displacement of the 1000th cycle - displacement of the first cycle). Finally, the amount of force required to cause clinical failure (30° ulnar deviation) of the repair was determined. RESULTS: Suture tape augmentation repairs displayed significantly less cyclic deformation (0.8 ± 0.5 mm) after cyclic loading than suture anchor repairs (1.8 ± 0.7 mm). There was no significant difference in the force required to cause the clinical failure of the repairs between the suture tape (35.1 ± 18.1 N) and suture anchor (24.5 ± 9.2 N) repairs. CONCLUSIONS: Index finger RCL repair with suture tape augmentation results in decreased deformation with repetitive motion compared with RCL repair alone. CLINICAL RELEVANCE: Suture tape augmentation may allow for early mobilization following index finger RCL repair by acting as a brace that protects the repaired ligament from deforming forces.
RESUMO
BACKGROUND: Partial tears of the distal biceps tendon can be difficult to diagnose based on clinical examination and magnetic resonance imaging (MRI). METHODS: Patients from a single surgeon's practice from 2000 to 2018 with a partial distal biceps tendon tear were retrospectively reviewed to determine the utility of the distal biceps palpation-rotation test in the detection of partial tears. This test is performed by palpating the bicipital tuberosity at the lateral forearm while ranging the forearm from supination to pronation with the arm adducted at the patient's side and the elbow flexed to 90°. A positive test elicits tenderness at the tuberosity with the arm in pronation but not in supination. Examination findings were correlated with MRI reports confirming a partial tear. Twelve cadaveric arms were dissected to determine overall pronosupination range of motion, the degree of pronation at which the bicipital tuberosity is maximally palpable, and anatomic measurements of the bicipital tuberosity to guide the optimal technique when carrying out the maneuver. RESULTS: Ninety-nine patients were diagnosed with a partial distal biceps tendon, of whom 34 had available MRI reports and complete physical examination documentation. Thirty-three of 34 patients (97%) had partial tears on MRI. The hook test was negative in all cases. All patients had tenderness with resisted supination. In those with MRI-confirmed partial tears, the palpation-rotation test was positive in all patients (100% sensitivity). The bicipital tuberosity was maximally palpated at the dorsolateral forearm at a mean 20° of pronation, and the proximal and distal boundaries of the radial tuberosity were 2.5 cm and 5.3 cm, on average, distal to the radial head, respectively. CONCLUSION: A positive palpation-rotation test was seen in 33 of 33 patients (100% sensitivity), as correlated with MRI. The combination of an intact distal biceps tendon within the antecubital fossa, tenderness on resisted supination, and a positive palpation-rotation test are highly suggestive of a partial distal biceps tendon tear.
Assuntos
Cotovelo , Traumatismos dos Tendões , Braço , Humanos , Palpação , Estudos Retrospectivos , Rotação , Ruptura , Traumatismos dos Tendões/diagnóstico por imagem , TendõesRESUMO
BACKGROUND: It has been shown that subacromial bursa (SAB) harbors connective tissue progenitor cells. The purpose of this study was to evaluate the effects of implantation of SAB-derived cells (SBCs) suspended in a fibrin sealant bead and implantation of SAB tissue at rotator cuff repair site on biomechanical properties of the repair in a mouse (C57Bl/6) model of supraspinatus tendon (ST) detachment and repair. METHODS: Part 1: Murine SAB tissue was harvested and cultured. Viability of SBCs suspended in 10 µL of fibrin sealant beads was confirmed in vitro and in vivo. Eighty mice underwent right ST detachment and repair augmented with either fibrin sealant bead (control group) or fibrin sealant bead with 100,000 SBCs (study group) applied at the repair site. Part 2: 120 mice underwent right ST detachment and repair and were randomized equally into 4 groups: (1) a tissue group, which received a piece of freshly harvested SAB tissue; (2) a cell group, which received SBCs suspended in fibrin sealant bead; (3) a fibrin sealant group, which received plain fibrin sealant bead without cells; and (4) a control group, which received nothing at the ST repair site. An equal number of mice in each group were killed at 2 and 4 weeks. Specimens underwent biomechanical testing to evaluate failure force (part 1 and 2) and histologic analysis of the repair site (part 1 only). RESULTS: Part 1: The mean failure force in the study group was significantly higher than controls at 2 and 4 weeks (3.25 ± 1.03 N vs. 2.43 ± 0.56 N, P = .01, and 4.08 ± 0.99 N vs. 3.02 ± 0.8 N, P = .004, respectively). Mean cell density of the ST at the repair site was significantly lower in the study group at 2 weeks than in controls (18,292.13 ± 1706.41 vs. 29,501.90 ± 3627.49, P = .001). Study group specimens had lower proteoglycan contents than controls, but this difference was not statistically significant. Part 2: There was no difference in failure force between cell and tissue groups at the 2- and 4-week time points (P = .994 and P = .603, respectively). There was no difference in failure force between fibrin sealant bead and control groups at the 2- and 4-week time points (P = .978 and P = .752, respectively). CONCLUSION: This study shows that the application of SBCs and SAB tissue at the rotator cuff repair site increases the strength of repair in a murine model of rotator cuff detachment and repair.