Clinical Reviews in Bone and Mineral Metabolism, 2005
Abstract Dysregulation of the bone morphogenic protein (BMP) 4-signaling pathway can explain many... more Abstract Dysregulation of the bone morphogenic protein (BMP) 4-signaling pathway can explain many developmental and postnatal features of fibrodysplasia ossificans progressive (FOP). However, many puzzling clinical features of the disease strongly implicate an ...
ASME 2012 Summer Bioengineering Conference, Parts A and B, 2012
ABSTRACT Rotator cuff tendon tears are common conditions which can alter shoulder joint function ... more ABSTRACT Rotator cuff tendon tears are common conditions which can alter shoulder joint function and over time, cause secondary damage to the surrounding tissues, including the cartilage and other remaining tendons. Glenohumeral joint stability is dependent on a dynamic balance between rotator cuff forces, in particular the subscapularis anteriorly and the infraspinatus posteriorly. An intact rotator cuff stabilizes the joint, allowing for concentric rotation of the humeral head on the glenoid. However, a massive rotator cuff tear involving the supraspinatus and infraspinatus may disrupt the normal balance of forces at the joint, resulting in abnormal joint loading. This is of particular concern in populations who perform activities requiring repeated overhead activity (e.g., laborers, athletes). Our lab has previously demonstrated that restoration of the subscapularis-infraspinatus anterior-posterior force balance improves shoulder function by providing a stable fulcrum for concentric rotation of the humeral head on the glenoid [1]. However, the long term consequences caused by disruption of the anterior-posterior force balance (supraspinatus and infraspinatus tear) on the glenoid cartilage and adjacent (intact) tendons, particularly in the case of an overuse population, remains unknown. Therefore, the objective of this study was to investigate the effect of disrupting the anterior-posterior force balance on joint function and joint damage using a clinically relevant overuse model system. We hypothesized that a disrupted anterior-posterior force balance (supraspinatus and infraspinatus tear) would result in H1) decreased joint function and H2) inferior adjacent tissue (glenoid cartilage, biceps and subscapularis tendon) properties compared to an intact anterior-posterior force balance (supraspinatus only tear).
The study objective is to examine the analgesic effect of 3 doses of dexamethasone in combination... more The study objective is to examine the analgesic effect of 3 doses of dexamethasone in combination with low concentration local anesthetics to determine the lowest effective dose of dexamethasone for use as an adjuvant in supraclavicular brachial plexus nerve block. The design is a prospective randomized double-blinded clinical study. The setting is an academic medical center. The patients are 89 adult patients scheduled for shoulder arthroscopy. All patients were randomly assigned into 1 of 4 treatment groups: (i) bupivacaine, 0.25% 30 mL; (ii) bupivacaine, 0.25% 30 mL with 1-mg preservative-free dexamethasone; (iii) bupivacaine, 0.25% 30 mL with 2-mg preservative-free dexamethasone; and (iv) bupivacaine, 0.25% 30 mL with 4-mg preservative-free dexamethasone. All patients received ultrasound-guided supraclavicular brachial plexus nerve blocks and general anesthesia. The measurements are the duration of analgesia and motor block. The median analgesia duration of supraclavicular brach...
Clinical Reviews in Bone and Mineral Metabolism, 2005
... Frederick S. Kaplan, MD,1,2,4 David L. Glaser, MD,1,4 Eileen M. Shore, PhD,1,3,4 Gregory K. D... more ... Frederick S. Kaplan, MD,1,2,4 David L. Glaser, MD,1,4 Eileen M. Shore, PhD,1,3,4 Gregory K. Deirmengian, MD,1,4 Rishi Gupta, MD,1,4 Patricia Delai, MD,5 Rolf Morhart, MD,6 Roger Smith, MD,7 ... 10. Luchetti W, Cohen RB, Hahn GV, Rocke DM, Helpin M, Zasloff M, Kaplan FS. ...
Background Pathology in the long head of the biceps tendon often occurs in patients with rotator ... more Background Pathology in the long head of the biceps tendon often occurs in patients with rotator cuff tears. Arthroscopic tenotomy is the most common treatment. However, the role of the long head of the biceps at the shoulder and the consequences of surgical detachment on the remaining shoulder structures remain unknown. Questions/purposes We hypothesized that detachment of the long head of the biceps, in the presence of supraspinatus and infraspinatus tears, would decrease shoulder function and decrease mechanical and histologic properties of both the subscapularis tendon and the glenoid articular cartilage. Methods We detached the supraspinatus and infraspinatus or the supraspinatus, infraspinatus, and long head of the biceps after 4 weeks of overuse in a rat model. Animals were gradually returned to overuse activity after detachment. At 8 weeks, the subscapularis and glenoid cartilage biomechanical and histologic properties were evaluated and compared. Results The group with the supraspinatus, infraspinatus, and long head of the biceps detached had greater medial force and decreased change in propulsion, braking, and vertical force. This group also had an increased upper and lower subscapularis modulus but without any differences in glenoid cartilage modulus. Finally, this group had a significantly lower cell density in both the upper and lower subscapularis tendons, although cartilage histology was not different. Conclusions Detachment of the long head of the biceps tendon in the presence of a posterior-superior cuff tear resulted in improved shoulder function and less joint damage in this animal model. Clinical Relevance This study provides evidence in an animal model that supports the use of tenotomy for the management of long head of the biceps pathology in the presence of a two-tendon cuff tear. However, long-term clinical trials are required.
Cells with osteogenic potential can be found in a variety of tissues. Here we show that circulati... more Cells with osteogenic potential can be found in a variety of tissues. Here we show that circulating osteogenic precursor (COP) cells, a bone marrow-derived type I collagen+/CD45+ subpopulation of mononuclear adherent cells, are present in early preosseous fibroproliferative lesions in patients with fibrodysplasia ossificans progressiva (FOP) and nucleate heterotopic ossification (HO) in a murine in vivo implantation assay. Blood samples from patients with FOP with active episodes of HO contain significantly higher numbers of clonally derived COP cell colonies than patients with stable disease or unaffected individuals. The highest level of COP cells was found in a patient just before the clinical onset of an HO exacerbation. Our studies show that even COP cells derived from an unaffected individual can contribute to HO in genetically susceptible host tissue. The possibility that circulating, hematopoietic-derived cells with osteogenic potential can seed inflammatory sites has tremen...
BACKGROUND. Fibrodysplasia ossificans progressiva is a rare and disabling genetic condition chara... more BACKGROUND. Fibrodysplasia ossificans progressiva is a rare and disabling genetic condition characterized by congenital malformation of the great toes and by progressive heterotopic ossification in specific anatomic patterns. Most patients with fibrodysplasia ossificans progressiva are misdiagnosed early in life before the appearance of heterotopic ossification and undergo diagnostic procedures that can cause lifelong disability. Recently, the genetic cause of fibrodysplasia ossificans progressiva was identified, and definitive genetic testing for fibrodysplasia ossificans progressiva is now available before the appearance of heterotopic ossification. METHODS. We recently evaluated 7 children for diagnosis of fibrodysplasia ossificans progressiva before the onset of heterotopic ossification. A medical history, physical examination, and skeletal survey were obtained on all of the patients, as well as clinical genetic testing for the canonical fibrodysplasia ossificans progressiva mut...
Background-Biceps tendon pathology is common with rotator cuff tears. The mechanisms for biceps c... more Background-Biceps tendon pathology is common with rotator cuff tears. The mechanisms for biceps changes, and therefore its optimal treatment, are unknown. Our objective was to determine the effect of rotator cuff tears on regional biceps tendon pathology. We hypothesized that histological and compositional changes would appear before organizational changes, both would appear before mechanical changes, and changes would begin at the tendon's insertion site. Methods-Sixty-five Sprague-Dawley rats received either detachment of supraspinatus and infraspinatus tendons or sham surgery. Rats were sacrificed at 1, 4 or 8 weeks for regional measurements of histological, compositional, organizational (1, 4 and 8 weeks) or mechanical properties (4 and 8 weeks only). Results-One week following tendon detachments, decreased organization and more rounded cell shape were found in the intra-articular space of the biceps tendon. Aggrecan expression was increased along the entire length of the tendon while all other compositional changes were at the tendon's proximal insertion into bone only. With time, this disorganization and more rounded cell shape extended the length of the tendon. Organizational and cell shape changes also preceded detrimental mechanical changes, as decreased modulus in the intra-articular space was found after 8 weeks. Conclusions-Results support a degenerative component to pathology in the biceps tendon. Additionally, changes resembling a tendon exposed to compressive loading occurring first in the intra-articular space indicate that the biceps tendon plays an increased role as a load bearing structure against the humeral head in the presence of rotator cuff tears.
Background: The purpose of this study was to elucidate the mechanism of biceps tendon changes aft... more Background: The purpose of this study was to elucidate the mechanism of biceps tendon changes after rotator cuff tears. We hypothesized that increased loading on the biceps tendon after rotator cuff tears will result in further detrimental changes whereas decreased loading will result in increased organization and more normal tendon composition. In addition, we hypothesized that changes with altered loading will begin at the proximal insertion into bone and progress along the tendon length at later time points. Materials and methods: Supraspinatus and infraspinatus tendon detachments in rats were followed by various loading protocols at various time points. Regional changes in cellularity, cell shape, collagen organization, and matrix proteins of the long head of the biceps tendon were determined by histologic measures and immunohistochemistry. Results: Increased loading after detachments resulted in more disorganized collagen after only 1 week and compositional changes by 4 weeks. By 8 weeks, decreased loading resulted in increased organization, decreased cellularity, a more elongated cell shape, and more normal tendon composition. Organizational changes with increased loading began in the intra-articular space and progressed along the tendon length with time. Conclusions: Combined with previous findings of decreased mechanics with increased loading, these results show that increased compressive loading away from the proximal insertion into bone is a mechanism for biceps tendon pathology in the presence of rotator cuff tears. The striking improvements with decreased loading further support increased loading as a mechanism for biceps tendon pathology because removal of this load led to improvements in tendon histology, organization, and composition. Level of evidence: Basic Science Study.
Background: Obesity is linked to major health conditions and poor surgical outcomes. The impact o... more Background: Obesity is linked to major health conditions and poor surgical outcomes. The impact of obesity on self-perceived outcome after rotator cuff repair (RCR) is unclear. Materials and methods: We studied 154 patients who underwent RCR. Obesity was considered a body mass index (BMI) greater than 30. Preoperative and postoperative evaluations included the Disabilities of the Arm, Shoulder and Hand (DASH), Simple Shoulder Test, and visual analog scales for pain, function, and quality of life. Obese and control patients were compared for baseline demographics, surgical findings, and postoperative outcomes. Results: Our overall population had a mean BMI of 28.4 (95% confidence interval, 27.7-29.1). There were 57 obese patients (BMI >30) and 97 nonobese patients with 1-or 2-tendon rotator cuff tears. Mean followup was 54.8 weeks (range, 52.0-88.7 weeks). Preoperative DASH score was 45.2 for obese patients and 43.4 for control patients (P ¼ .524). The mean improvement in DASH score was 30.7 for obese patients and 26.1 for nonobese patients (P ¼ .152). There were no significant differences in the Simple Shoulder Test and visual analog scale scores. Worse follow-up DASH scores in both groups were associated with worker's compensation status (P ¼ .003) and total comorbidities (P < .001). Multiple linear regression analysis showed that BMI (continuous) and obesity (dichotomous) were not significantly related to outcome after we controlled for confounding variables. Conclusions: Although obesity is considered a risk factor for poor postoperative outcomes after some surgical procedures, in our experience, obesity does not have an independent, significant effect on selfreported early outcomes after RCR.
The number of total shoulder arthroplasty (TSA) cases continues to grow each year. With the incre... more The number of total shoulder arthroplasty (TSA) cases continues to grow each year. With the increasing number of procedures being performed, there, in turn, will exist a greater need for revision procedures. Failure of a shoulder arthroplasty can result from soft-tissue problems, bony deficiencies, infection, and component wear or loosening. Component loosening and osseous deficiencies may occur on the humeral and/or glenoid side. Multiple studies have identified glenoid component loosening as one of the more common causes necessitating revision after TSA. Glenohumeral joint instability in the setting of rotator cuff deficiency is also a common cause of glenoid loosening. Eccentric loading of the glenoid from proximal humeral migration leads to increased stress at the bonecement or bone-implant interface, commonly referred to as the ''rocking horse phenomenon.'' 19 Eccentric loading, instability, and glenoid loosening may also result from incomplete glenoid seating, glenoid or humeral component malpositioning, or tuberosity malunion. The importance of glenoid implantation becomes evident when one considers outcomes in patients who undergo revision surgery for failed glenoid components. Multiple studies have underscored the importance of glenoid component reimplantation in determining functional outcome. Principles of glenoid component design followed by a discussion of the literature, suggesting poor results in revision settings, will be presented in this article. This will be followed by a discussion of current and emerging treatment options for this problem. The concepts and techniques discussed assume an intact rotator cuff and the absence of infection because these topics are beyond the scope of this article. Loosening of the glenoid component remains one of the most likely causes of implant failure in TSA. This is almost always multifactorial in its etiology. Contributing factors may include mechanical failure of the fixation in response to high tensile stress or osteolysis of the surrounding bone stock in response to particulate wear debris. Design changes and techniques to improve long-term glenoid stability have included preservation of the subchondral plate, concentric glenoid reaming, and optimal biomaterial selection and design. More recent studies have suggested that improved glenoid component design and more precise instrumentation play a vital role in enhancing initial No institutional review board approval was required for this review.
Augmentation materials for rotator cuff tears, such as small intestine submucosa (SIS), have been... more Augmentation materials for rotator cuff tears, such as small intestine submucosa (SIS), have been used with the goal of improving outcome. Knowledge is limited on the use of SIS in animal models of acute and chronic rotator cuff tears. We hypothesized that the use of SIS in the surgical management of full thickness supraspinatus tears would improve histologic and biomechanical properties. Results show temporal improvements in several histologic parameters. Both acute and chronic injuries repaired with SIS have similar and increased mechanical properties respectively, compared to those repaired without SIS. In general, acute repairs with SIS were comparable to acute repairs without SIS. In chronic repairs, the use of SIS significantly reduced the cross sectional area of the healing tendon and increased the modulus. These results provide information on the use of SIS for rotator cuff repairs.
Young patients with glenohumeral joint arthritis are difficult to treat. Though total shoulder ar... more Young patients with glenohumeral joint arthritis are difficult to treat. Though total shoulder arthroplasty (TSA) and hemiarthroplasty provide reliable pain relief and restoration of function in this population, concerns regarding longevity, particularly of the glenoid component, persistent in active patients. Sperling et al 11,12 have studied long-term outcomes of TSA and hemiarthroplasty in patients less than 50 years of age and have noted 68% rate of radiographic glenoid erosions in hemiarthroplasty and a 59% glenoid lucency rate in TSA. Most importantly, at minimum of 5 years, both treatment options had an unsatisfactory radiographic rating of more than 50%. As a result, some shoulder surgeons consider biological resurfacing of the glenoid as a potential means of pain relief, while preserving glenoid bone stock and avoiding polyethylene-related problems. The primary indication for biologic glenoid resurfacing is the presence of arthritis in an active patient who expects to return to sports or work activities and in whom conservative management with activity modification, anti-inflammatory medication, injections, and physical therapy has failed. Furthermore, patients who have not attained adequate pain relief with arthroscopic debridement and/or capsular release are also considered for this procedure. Patients are often considered unacceptable for glenoid resurfacing on the basis of age and/or inordinate functional demands that could make the patient prone to early loosening. Though chronologic age has been recognized as an important factor, physiologic age, activity level, and patient expectations are perhaps more important decision-making variables. Contraindications to soft-tissue glenoid resurfacing include major glenoid osseous deficiency, prior glenoid resurfacing, advanced rheumatoid arthritis, and active infection. Resurfacing employs a means of biologic interposition with a variety of graft materials. Techniques have been described using autograft anterior capsule, autograft fascia lata, tendoachilles allograft, lateral meniscal allograft, and a variety of commercially available grafts/scaffolds. 3,4,6-8,10,14 No study has specifically evaluated durability of different graft materials, and there is no ''gold standard''. Furthermore, there remains a lack of consensus regarding the expected outcomes of biological glenoid resurfacing. The purpose of this study was to critically examine the outcomes of biologic glenoid resurfacing in the treatment of glenohumeral arthritis and to present an evidence-based synthesis of the available literature. Specifically, we sought to answer the following questions: 1) What are the demographics of patients treated with biologic glenoid resurfacing? 2) What are the subjective and objective outcomes and is there any difference in outcome based on graft material used or surgical technique? 3) What are potential complications associated with this technique and how often are these reported? 4) Is the available literature sufficient to provide guidance regarding the efficacy of this technique for treatment of glenohumeral arthritis? Methods We searched the Medline and EMBASE computerized literature databases from January 1950 to November 2010. Articles were IRB: Review Article so not applicable.
Background: The number of times an article has been cited has been used as a marker of its influe... more Background: The number of times an article has been cited has been used as a marker of its influence in a medical specialty. The purpose of this study was to determine the 50 most cited articles in shoulder surgery and their characteristics. Methods: Science Citation Index Expanded was searched for citations of articles published in any of the 61 journals in the category ''Orthopedics.'' Each of the journals was searched to determine the 50 most often cited articles specific to shoulder surgery. The following characteristics were determined for each article: authors, year of publication, source journal, geographic origin, article type, and level of evidence for clinical articles. Citation density (total number of citations/years since publication) was also determined. Results: The number of citations ranged from 1211 to 192. The 50 most often cited articles were published in 8 journals. The majority of the articles (42) were clinical, with the remaining representing some type of basic science research. The most common level of evidence was IV (23). The mean number of citations for methodologic articles (437 citations per article) was greater than that for non-methodologic articles (301 citations per article) (P ¼ .034). Conclusions: Articles that introduced instruments for outcome evaluation or that introduced classification systems (methodologic) were highly cited regardless of the date of publication. The top 50 list presented provides residency and fellowship directors with a group of ''classic'' articles in the subspecialty of orthopedic shoulder surgery that can be included in reading curriculums for their trainees. Level of evidence: Review Article.
Clinical Reviews in Bone and Mineral Metabolism, 2005
Abstract Dysregulation of the bone morphogenic protein (BMP) 4-signaling pathway can explain many... more Abstract Dysregulation of the bone morphogenic protein (BMP) 4-signaling pathway can explain many developmental and postnatal features of fibrodysplasia ossificans progressive (FOP). However, many puzzling clinical features of the disease strongly implicate an ...
ASME 2012 Summer Bioengineering Conference, Parts A and B, 2012
ABSTRACT Rotator cuff tendon tears are common conditions which can alter shoulder joint function ... more ABSTRACT Rotator cuff tendon tears are common conditions which can alter shoulder joint function and over time, cause secondary damage to the surrounding tissues, including the cartilage and other remaining tendons. Glenohumeral joint stability is dependent on a dynamic balance between rotator cuff forces, in particular the subscapularis anteriorly and the infraspinatus posteriorly. An intact rotator cuff stabilizes the joint, allowing for concentric rotation of the humeral head on the glenoid. However, a massive rotator cuff tear involving the supraspinatus and infraspinatus may disrupt the normal balance of forces at the joint, resulting in abnormal joint loading. This is of particular concern in populations who perform activities requiring repeated overhead activity (e.g., laborers, athletes). Our lab has previously demonstrated that restoration of the subscapularis-infraspinatus anterior-posterior force balance improves shoulder function by providing a stable fulcrum for concentric rotation of the humeral head on the glenoid [1]. However, the long term consequences caused by disruption of the anterior-posterior force balance (supraspinatus and infraspinatus tear) on the glenoid cartilage and adjacent (intact) tendons, particularly in the case of an overuse population, remains unknown. Therefore, the objective of this study was to investigate the effect of disrupting the anterior-posterior force balance on joint function and joint damage using a clinically relevant overuse model system. We hypothesized that a disrupted anterior-posterior force balance (supraspinatus and infraspinatus tear) would result in H1) decreased joint function and H2) inferior adjacent tissue (glenoid cartilage, biceps and subscapularis tendon) properties compared to an intact anterior-posterior force balance (supraspinatus only tear).
The study objective is to examine the analgesic effect of 3 doses of dexamethasone in combination... more The study objective is to examine the analgesic effect of 3 doses of dexamethasone in combination with low concentration local anesthetics to determine the lowest effective dose of dexamethasone for use as an adjuvant in supraclavicular brachial plexus nerve block. The design is a prospective randomized double-blinded clinical study. The setting is an academic medical center. The patients are 89 adult patients scheduled for shoulder arthroscopy. All patients were randomly assigned into 1 of 4 treatment groups: (i) bupivacaine, 0.25% 30 mL; (ii) bupivacaine, 0.25% 30 mL with 1-mg preservative-free dexamethasone; (iii) bupivacaine, 0.25% 30 mL with 2-mg preservative-free dexamethasone; and (iv) bupivacaine, 0.25% 30 mL with 4-mg preservative-free dexamethasone. All patients received ultrasound-guided supraclavicular brachial plexus nerve blocks and general anesthesia. The measurements are the duration of analgesia and motor block. The median analgesia duration of supraclavicular brach...
Clinical Reviews in Bone and Mineral Metabolism, 2005
... Frederick S. Kaplan, MD,1,2,4 David L. Glaser, MD,1,4 Eileen M. Shore, PhD,1,3,4 Gregory K. D... more ... Frederick S. Kaplan, MD,1,2,4 David L. Glaser, MD,1,4 Eileen M. Shore, PhD,1,3,4 Gregory K. Deirmengian, MD,1,4 Rishi Gupta, MD,1,4 Patricia Delai, MD,5 Rolf Morhart, MD,6 Roger Smith, MD,7 ... 10. Luchetti W, Cohen RB, Hahn GV, Rocke DM, Helpin M, Zasloff M, Kaplan FS. ...
Background Pathology in the long head of the biceps tendon often occurs in patients with rotator ... more Background Pathology in the long head of the biceps tendon often occurs in patients with rotator cuff tears. Arthroscopic tenotomy is the most common treatment. However, the role of the long head of the biceps at the shoulder and the consequences of surgical detachment on the remaining shoulder structures remain unknown. Questions/purposes We hypothesized that detachment of the long head of the biceps, in the presence of supraspinatus and infraspinatus tears, would decrease shoulder function and decrease mechanical and histologic properties of both the subscapularis tendon and the glenoid articular cartilage. Methods We detached the supraspinatus and infraspinatus or the supraspinatus, infraspinatus, and long head of the biceps after 4 weeks of overuse in a rat model. Animals were gradually returned to overuse activity after detachment. At 8 weeks, the subscapularis and glenoid cartilage biomechanical and histologic properties were evaluated and compared. Results The group with the supraspinatus, infraspinatus, and long head of the biceps detached had greater medial force and decreased change in propulsion, braking, and vertical force. This group also had an increased upper and lower subscapularis modulus but without any differences in glenoid cartilage modulus. Finally, this group had a significantly lower cell density in both the upper and lower subscapularis tendons, although cartilage histology was not different. Conclusions Detachment of the long head of the biceps tendon in the presence of a posterior-superior cuff tear resulted in improved shoulder function and less joint damage in this animal model. Clinical Relevance This study provides evidence in an animal model that supports the use of tenotomy for the management of long head of the biceps pathology in the presence of a two-tendon cuff tear. However, long-term clinical trials are required.
Cells with osteogenic potential can be found in a variety of tissues. Here we show that circulati... more Cells with osteogenic potential can be found in a variety of tissues. Here we show that circulating osteogenic precursor (COP) cells, a bone marrow-derived type I collagen+/CD45+ subpopulation of mononuclear adherent cells, are present in early preosseous fibroproliferative lesions in patients with fibrodysplasia ossificans progressiva (FOP) and nucleate heterotopic ossification (HO) in a murine in vivo implantation assay. Blood samples from patients with FOP with active episodes of HO contain significantly higher numbers of clonally derived COP cell colonies than patients with stable disease or unaffected individuals. The highest level of COP cells was found in a patient just before the clinical onset of an HO exacerbation. Our studies show that even COP cells derived from an unaffected individual can contribute to HO in genetically susceptible host tissue. The possibility that circulating, hematopoietic-derived cells with osteogenic potential can seed inflammatory sites has tremen...
BACKGROUND. Fibrodysplasia ossificans progressiva is a rare and disabling genetic condition chara... more BACKGROUND. Fibrodysplasia ossificans progressiva is a rare and disabling genetic condition characterized by congenital malformation of the great toes and by progressive heterotopic ossification in specific anatomic patterns. Most patients with fibrodysplasia ossificans progressiva are misdiagnosed early in life before the appearance of heterotopic ossification and undergo diagnostic procedures that can cause lifelong disability. Recently, the genetic cause of fibrodysplasia ossificans progressiva was identified, and definitive genetic testing for fibrodysplasia ossificans progressiva is now available before the appearance of heterotopic ossification. METHODS. We recently evaluated 7 children for diagnosis of fibrodysplasia ossificans progressiva before the onset of heterotopic ossification. A medical history, physical examination, and skeletal survey were obtained on all of the patients, as well as clinical genetic testing for the canonical fibrodysplasia ossificans progressiva mut...
Background-Biceps tendon pathology is common with rotator cuff tears. The mechanisms for biceps c... more Background-Biceps tendon pathology is common with rotator cuff tears. The mechanisms for biceps changes, and therefore its optimal treatment, are unknown. Our objective was to determine the effect of rotator cuff tears on regional biceps tendon pathology. We hypothesized that histological and compositional changes would appear before organizational changes, both would appear before mechanical changes, and changes would begin at the tendon's insertion site. Methods-Sixty-five Sprague-Dawley rats received either detachment of supraspinatus and infraspinatus tendons or sham surgery. Rats were sacrificed at 1, 4 or 8 weeks for regional measurements of histological, compositional, organizational (1, 4 and 8 weeks) or mechanical properties (4 and 8 weeks only). Results-One week following tendon detachments, decreased organization and more rounded cell shape were found in the intra-articular space of the biceps tendon. Aggrecan expression was increased along the entire length of the tendon while all other compositional changes were at the tendon's proximal insertion into bone only. With time, this disorganization and more rounded cell shape extended the length of the tendon. Organizational and cell shape changes also preceded detrimental mechanical changes, as decreased modulus in the intra-articular space was found after 8 weeks. Conclusions-Results support a degenerative component to pathology in the biceps tendon. Additionally, changes resembling a tendon exposed to compressive loading occurring first in the intra-articular space indicate that the biceps tendon plays an increased role as a load bearing structure against the humeral head in the presence of rotator cuff tears.
Background: The purpose of this study was to elucidate the mechanism of biceps tendon changes aft... more Background: The purpose of this study was to elucidate the mechanism of biceps tendon changes after rotator cuff tears. We hypothesized that increased loading on the biceps tendon after rotator cuff tears will result in further detrimental changes whereas decreased loading will result in increased organization and more normal tendon composition. In addition, we hypothesized that changes with altered loading will begin at the proximal insertion into bone and progress along the tendon length at later time points. Materials and methods: Supraspinatus and infraspinatus tendon detachments in rats were followed by various loading protocols at various time points. Regional changes in cellularity, cell shape, collagen organization, and matrix proteins of the long head of the biceps tendon were determined by histologic measures and immunohistochemistry. Results: Increased loading after detachments resulted in more disorganized collagen after only 1 week and compositional changes by 4 weeks. By 8 weeks, decreased loading resulted in increased organization, decreased cellularity, a more elongated cell shape, and more normal tendon composition. Organizational changes with increased loading began in the intra-articular space and progressed along the tendon length with time. Conclusions: Combined with previous findings of decreased mechanics with increased loading, these results show that increased compressive loading away from the proximal insertion into bone is a mechanism for biceps tendon pathology in the presence of rotator cuff tears. The striking improvements with decreased loading further support increased loading as a mechanism for biceps tendon pathology because removal of this load led to improvements in tendon histology, organization, and composition. Level of evidence: Basic Science Study.
Background: Obesity is linked to major health conditions and poor surgical outcomes. The impact o... more Background: Obesity is linked to major health conditions and poor surgical outcomes. The impact of obesity on self-perceived outcome after rotator cuff repair (RCR) is unclear. Materials and methods: We studied 154 patients who underwent RCR. Obesity was considered a body mass index (BMI) greater than 30. Preoperative and postoperative evaluations included the Disabilities of the Arm, Shoulder and Hand (DASH), Simple Shoulder Test, and visual analog scales for pain, function, and quality of life. Obese and control patients were compared for baseline demographics, surgical findings, and postoperative outcomes. Results: Our overall population had a mean BMI of 28.4 (95% confidence interval, 27.7-29.1). There were 57 obese patients (BMI >30) and 97 nonobese patients with 1-or 2-tendon rotator cuff tears. Mean followup was 54.8 weeks (range, 52.0-88.7 weeks). Preoperative DASH score was 45.2 for obese patients and 43.4 for control patients (P ¼ .524). The mean improvement in DASH score was 30.7 for obese patients and 26.1 for nonobese patients (P ¼ .152). There were no significant differences in the Simple Shoulder Test and visual analog scale scores. Worse follow-up DASH scores in both groups were associated with worker's compensation status (P ¼ .003) and total comorbidities (P < .001). Multiple linear regression analysis showed that BMI (continuous) and obesity (dichotomous) were not significantly related to outcome after we controlled for confounding variables. Conclusions: Although obesity is considered a risk factor for poor postoperative outcomes after some surgical procedures, in our experience, obesity does not have an independent, significant effect on selfreported early outcomes after RCR.
The number of total shoulder arthroplasty (TSA) cases continues to grow each year. With the incre... more The number of total shoulder arthroplasty (TSA) cases continues to grow each year. With the increasing number of procedures being performed, there, in turn, will exist a greater need for revision procedures. Failure of a shoulder arthroplasty can result from soft-tissue problems, bony deficiencies, infection, and component wear or loosening. Component loosening and osseous deficiencies may occur on the humeral and/or glenoid side. Multiple studies have identified glenoid component loosening as one of the more common causes necessitating revision after TSA. Glenohumeral joint instability in the setting of rotator cuff deficiency is also a common cause of glenoid loosening. Eccentric loading of the glenoid from proximal humeral migration leads to increased stress at the bonecement or bone-implant interface, commonly referred to as the ''rocking horse phenomenon.'' 19 Eccentric loading, instability, and glenoid loosening may also result from incomplete glenoid seating, glenoid or humeral component malpositioning, or tuberosity malunion. The importance of glenoid implantation becomes evident when one considers outcomes in patients who undergo revision surgery for failed glenoid components. Multiple studies have underscored the importance of glenoid component reimplantation in determining functional outcome. Principles of glenoid component design followed by a discussion of the literature, suggesting poor results in revision settings, will be presented in this article. This will be followed by a discussion of current and emerging treatment options for this problem. The concepts and techniques discussed assume an intact rotator cuff and the absence of infection because these topics are beyond the scope of this article. Loosening of the glenoid component remains one of the most likely causes of implant failure in TSA. This is almost always multifactorial in its etiology. Contributing factors may include mechanical failure of the fixation in response to high tensile stress or osteolysis of the surrounding bone stock in response to particulate wear debris. Design changes and techniques to improve long-term glenoid stability have included preservation of the subchondral plate, concentric glenoid reaming, and optimal biomaterial selection and design. More recent studies have suggested that improved glenoid component design and more precise instrumentation play a vital role in enhancing initial No institutional review board approval was required for this review.
Augmentation materials for rotator cuff tears, such as small intestine submucosa (SIS), have been... more Augmentation materials for rotator cuff tears, such as small intestine submucosa (SIS), have been used with the goal of improving outcome. Knowledge is limited on the use of SIS in animal models of acute and chronic rotator cuff tears. We hypothesized that the use of SIS in the surgical management of full thickness supraspinatus tears would improve histologic and biomechanical properties. Results show temporal improvements in several histologic parameters. Both acute and chronic injuries repaired with SIS have similar and increased mechanical properties respectively, compared to those repaired without SIS. In general, acute repairs with SIS were comparable to acute repairs without SIS. In chronic repairs, the use of SIS significantly reduced the cross sectional area of the healing tendon and increased the modulus. These results provide information on the use of SIS for rotator cuff repairs.
Young patients with glenohumeral joint arthritis are difficult to treat. Though total shoulder ar... more Young patients with glenohumeral joint arthritis are difficult to treat. Though total shoulder arthroplasty (TSA) and hemiarthroplasty provide reliable pain relief and restoration of function in this population, concerns regarding longevity, particularly of the glenoid component, persistent in active patients. Sperling et al 11,12 have studied long-term outcomes of TSA and hemiarthroplasty in patients less than 50 years of age and have noted 68% rate of radiographic glenoid erosions in hemiarthroplasty and a 59% glenoid lucency rate in TSA. Most importantly, at minimum of 5 years, both treatment options had an unsatisfactory radiographic rating of more than 50%. As a result, some shoulder surgeons consider biological resurfacing of the glenoid as a potential means of pain relief, while preserving glenoid bone stock and avoiding polyethylene-related problems. The primary indication for biologic glenoid resurfacing is the presence of arthritis in an active patient who expects to return to sports or work activities and in whom conservative management with activity modification, anti-inflammatory medication, injections, and physical therapy has failed. Furthermore, patients who have not attained adequate pain relief with arthroscopic debridement and/or capsular release are also considered for this procedure. Patients are often considered unacceptable for glenoid resurfacing on the basis of age and/or inordinate functional demands that could make the patient prone to early loosening. Though chronologic age has been recognized as an important factor, physiologic age, activity level, and patient expectations are perhaps more important decision-making variables. Contraindications to soft-tissue glenoid resurfacing include major glenoid osseous deficiency, prior glenoid resurfacing, advanced rheumatoid arthritis, and active infection. Resurfacing employs a means of biologic interposition with a variety of graft materials. Techniques have been described using autograft anterior capsule, autograft fascia lata, tendoachilles allograft, lateral meniscal allograft, and a variety of commercially available grafts/scaffolds. 3,4,6-8,10,14 No study has specifically evaluated durability of different graft materials, and there is no ''gold standard''. Furthermore, there remains a lack of consensus regarding the expected outcomes of biological glenoid resurfacing. The purpose of this study was to critically examine the outcomes of biologic glenoid resurfacing in the treatment of glenohumeral arthritis and to present an evidence-based synthesis of the available literature. Specifically, we sought to answer the following questions: 1) What are the demographics of patients treated with biologic glenoid resurfacing? 2) What are the subjective and objective outcomes and is there any difference in outcome based on graft material used or surgical technique? 3) What are potential complications associated with this technique and how often are these reported? 4) Is the available literature sufficient to provide guidance regarding the efficacy of this technique for treatment of glenohumeral arthritis? Methods We searched the Medline and EMBASE computerized literature databases from January 1950 to November 2010. Articles were IRB: Review Article so not applicable.
Background: The number of times an article has been cited has been used as a marker of its influe... more Background: The number of times an article has been cited has been used as a marker of its influence in a medical specialty. The purpose of this study was to determine the 50 most cited articles in shoulder surgery and their characteristics. Methods: Science Citation Index Expanded was searched for citations of articles published in any of the 61 journals in the category ''Orthopedics.'' Each of the journals was searched to determine the 50 most often cited articles specific to shoulder surgery. The following characteristics were determined for each article: authors, year of publication, source journal, geographic origin, article type, and level of evidence for clinical articles. Citation density (total number of citations/years since publication) was also determined. Results: The number of citations ranged from 1211 to 192. The 50 most often cited articles were published in 8 journals. The majority of the articles (42) were clinical, with the remaining representing some type of basic science research. The most common level of evidence was IV (23). The mean number of citations for methodologic articles (437 citations per article) was greater than that for non-methodologic articles (301 citations per article) (P ¼ .034). Conclusions: Articles that introduced instruments for outcome evaluation or that introduced classification systems (methodologic) were highly cited regardless of the date of publication. The top 50 list presented provides residency and fellowship directors with a group of ''classic'' articles in the subspecialty of orthopedic shoulder surgery that can be included in reading curriculums for their trainees. Level of evidence: Review Article.
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Papers by David Glaser