Journal of shoulder and elbow surgery / American Shoulder and Elbow Surgeons ... [et al.], Jan 13, 2015
Periprosthetic joint infection (PJI) is a major cause of morbidity after shoulder arthroplasty. P... more Periprosthetic joint infection (PJI) is a major cause of morbidity after shoulder arthroplasty. PJI epidemiology has not been well studied. We aimed to analyze the historical incidence, predisposing factors, and economic burden of PJI after shoulder arthroplasty in the United States. Primary shoulder arthroplasty patients were identified by the International Classification of Diseases, Ninth Revision, Clinical Modification codes 81.80 (total shoulder arthroplasty), 81.81 (hemiarthroplasty), and 81.88 (reverse arthroplasty) in the Nationwide Inpatient Sample from 2002 to 2011. PJI was identified by codes 80.01 (arthrotomy for device removal) and 996.66 (prosthetic infection). Multivariate logistic regression analysis was used to identify predisposing factors for PJI. PJI rate was 0.98% from 2002 to 2011 and did not vary significantly. Comorbidities associated with PJI were weight loss/nutritional deficiency (odds ratio [OR], 2.62; 95% confidence interval [CI], 1.53-4.51; P = .00047),...
Journal of shoulder and elbow surgery / American Shoulder and Elbow Surgeons ... [et al.], Jan 4, 2014
The incidence of failed rotator cuff repairs remains high, especially in the setting of massive t... more The incidence of failed rotator cuff repairs remains high, especially in the setting of massive tears or revision repairs. The purpose of this study was to evaluate patient outcomes and repair integrity after augmentation with the repair patch, a poly-l-lactide synthetic polymer. Sixteen consecutive patients with massive or recurrent rotator cuff tears underwent open repair with synthetic poly-l-lactide patch augmentation. Two patients required the patch to bridge defects, and 1 patient retore after a motor vehicle accident and had revision surgery at another institution. The 13 remaining patients were retrospectively evaluated from 1.2 to 1.7 years (average, 1.5 years) after surgery by PENN, American Shoulder and Elbow Surgeons, and Single Assessment Numeric Evaluation scores. Magnetic resonance imaging was used to examine the integrity of the repair at a minimum of 1 year of follow-up. The mean age was 57.3 years (42-68 years). Five patients (38%) had an intact rotator cuff at the...
Journal of shoulder and elbow surgery / American Shoulder and Elbow Surgeons ... [et al.], 2014
The introduction of the reverse shoulder arthroplasty has provided shoulder surgeons with more op... more The introduction of the reverse shoulder arthroplasty has provided shoulder surgeons with more options for the treatment of complex proximal humeral fractures in the elderly. Early reported results suggest that the average functional outcome may be better than hemiarthroplasty in certain patients and specific clinical scenarios. In addition, these results seem to be reached more quickly with less dependence on rehabilitation. The reverse prosthesis may be particularly useful in patients aged older than 70 years, especially those with severely comminuted fractures in osteopenic bone. These factors likely have a negative impact on the results of hemiarthroplasty and internal fixation. Despite the potential benefits of reverse arthroplasty for fracture, there is a significant learning curve with the use of this prosthesis, and it has its own set of complications. The surgeon must show appropriate judgment when selecting a reverse arthroplasty in the setting of a proximal humeral fractu...
We retrospectively reviewed 68 patients (70 shoulders) who underwent either open or arthroscopic ... more We retrospectively reviewed 68 patients (70 shoulders) who underwent either open or arthroscopic acromioplasty performed by a single surgeon (JPI) for chronic impingement syndrome in the presence of an intact rotator cuff. Group 1 consisted of 24 shoulders that had open acromioplasty and group 2 consisted of 46 shoulders that had arthroscopic acromioplasty. The minimum follow-up was 12 months for both groups. There was no statistical difference in mean postoperative shoulder scores between the operative groups. However, there were more excellent results in the open group as compared with the arthroscopic group (54.2% vs 41.9%, respectively). In addition, there was a higher percentage of poor results in group 2 as compared with group 1 (27.9% vs 16.6%, respectively). Arthroscopic acromioplasty was associated with shorter hospital stays and faster achievement of maximal pain relief as compared with open acromioplasty. Examination of postoperative radiographs often revealed subacromial calcifications. These calcifications were more frequent after arthroscopic acromioplasty and were associated with a worse result.
Hypothesis: This study evaluated the intra-rater and inter-rater correlation of 3 commonly used x... more Hypothesis: This study evaluated the intra-rater and inter-rater correlation of 3 commonly used x-ray image classifications and defined the clinical factors most correlated with a surgical recommendation for a hemiarthroplasty or a reverse total shoulder arthroplasty (RSA) for treatment of rotator cuff tear arthropathy (CTA). We hypothesized that specific radiographic criteria and clinical criteria would be most important and consistently used among experienced shoulder surgeons when determining the best surgical option for a particular patient. Methods: Four experienced orthopedic surgeons evaluated standard anteroposterior radiographs and the clinical examination of 37 shoulders with CTA. On each reading, they classified the grade of pathology using the Seebauer, Favard, and Hamada classifications. Using radiographic criteria alone, or with the clinical findings, each evaluator determined the recommended prosthetic treatment for each shoulder. Results: Intra-rater correlations for surgical recommendations using radiographic criteria ranged from 0.39 to 1.0 and improved in 3 of 4 evaluators when the clinical examination was included in the clinical decision. The inter-rater reliability using these same criteria were fair, at 0.32 for radiographic and .35 for radiographic and clinical data. The most significant radiographic factors associated with a surgical decision were the degree of humeral head superior migration and the escape of the humeral head from the coracoacromial arch. Clinical factors most associated with the decision for RSA were advanced age, loss of shoulder elevation, superior humeral head escape, and pseudoparalysis of the shoulder. Radiographic findings had a less significant effect on surgical recommendations when clinical factors were included. Conclusion: Clinical and radiographic criteria are needed for a decision for hemiarthroplasty or RSA in the treatment of CTA. A treatment algorithm based upon radiographic and clinical criteria is proposed. Level of evidence: Level III. Diagnostic Agreement Study With Nonconsecutive Patients.
Although rotator cuff repair is often successful at relieving pain, the repaired insertion site f... more Although rotator cuff repair is often successful at relieving pain, the repaired insertion site frequently fails. Mechanical properties of the repair improved when the shoulder was immobilized in an animal model, but joint stiffness and range of motion were not evaluated. The objective of this study was to measure rotational mechanics before and after shoulders were immobilized after cuff injury and repair, not immobilized after cuff injury and repair, and immobilized without injury and repair. Humeral rotation was significantly less 4 and 8 weeks after injury and repair but did not decrease significantly when the injured and repaired shoulder was immobilized. Rotational stiffness increased significantly 4 and 8 weeks after injury and repair and was significantly greater at 4, but not 8, weeks when the injured and repaired shoulders were immobilized. This study demonstrated that the increase in joint stiffness caused by immobilizing an injured and repaired shoulder was transient and, therefore, does not outweigh the long-term benefits of immobilization on improved tendon to bone healing. (J Shoulder Elbow Surg 2008;17:108S-113S.)
Scapular notching in reverse shoulder arthroplasty appears to be a multifactorial problem related... more Scapular notching in reverse shoulder arthroplasty appears to be a multifactorial problem related to both implant and patient factors. There are well-established guidelines for implant position. Recent cadaveric studies have illustrated anatomic factors that need further consideration. Scapular neck length and inferior glenoid tubercle morphology may be major factors predicting scapular notching. From 2 institutions, we reviewed 3 years of patient radiographs for reverse shoulder arthroplasty, including all reverse shoulder arthroplasties at least 12 months from surgery. We used true anterior-posterior radiographs, both preoperatively and postoperatively, and focused on the "ideal" positioning of the glenosphere: at or below the inferior margin of the glenoid, and neutral or slight inferior tilt. Radiographs were reviewed by 2 independent surgeons. Glenoid articular surface height was measured along with scapular neck length and notching presence. Of 64 sets of radiographs reviewed, 50 met inclusion criteria. Notching was present in only 25 (50%) of the sets. The mean scapular neck length was 8.9 mm with a neck:surface ratio of 0.23 in the notching present group and 12.1 mm with a neck:surface ratio of 0.32 in the notching absent group. Significance was reached with both scapular neck length and neck:surface ratio (P = .0012 and P = .0006, respectively). There is a high degree of significance that patient anatomy does play a role in the occurrence of notching. Surgeons may consider lateralizing the glenosphere in patients with a scapular neck length of less than 9 mm measured on a true anteroposterior radiograph. Anatomy study, imaging.
We retrospectively reviewed 32 patients who underwent glenoid revision surgery after total should... more We retrospectively reviewed 32 patients who underwent glenoid revision surgery after total shoulder arthroplasty to compare the results of revision total shoulder arthroplasty with those of revision hemiarthroplasty and to identify factors associated with poor results after revision shoulder arthroplasty for glenoid component loosening. Results were reviewed at a mean follow-up of 4 years (range, 2-8 years). Glenoid reimplantation resulted in significant pain relief (P Ͻ .0001), improvement in American Shoulder and Elbow Surgeons (ASES) score (P Ͻ .02), and external rotation (24°to 44°, P Ͻ .004). Revision to a hemiarthroplasty also resulted in significant pain relief (P Ͻ .01) and improvement in ASES score (P Ͻ .05). For the treatment of glenoid loosening without glenohumeral instability, both reimplantation of a glenoid component and revision to a hemiarthroplasty improved function, satisfaction, and level of pain. Reimplantation of a new glenoid component offered greater improvements in pain (P Ͻ .008) and external rotation (increase of 20°v ersus 3°, P Ͻ .03) compared with hemiarthroplasty. For patients with preoperative glenohumeral instability, revision surgery did not improve motion, function, or pain significantly. Risk factors associated with a poor outcome after revision arthroplasty included persistent glenohumeral instability, rotator cuff tears, and malunion of the greater tuberosity. (J Shoulder Elbow Surg 2007;16: 706-716.) Symptomatic loosening of the glenoid component is one of the most common complications associated with total shoulder arthroplasty (TSA). 7,28,38 Although the incidence of component loosening requiring revision surgery is low (0%-4.2%), this complication represents approximately 25% of all complications related to TSA. 7, Similarly, few reports exist in the literature regarding the outcome of revision surgery for glenoid component loosening. Etiologic factors associated with aseptic glenoid component loosening include irreparable tears of the rotator cuff, component malposition, tuberosity malunion, and glenohumeral instability. Each of these factors can independently or in combination lead to eccentric loads borne on the glenoid component. Eccentric load increases stresses at the bonecement interface and increases micro motion of the glenoid component, which can lead to component loosening. Franklin et al 11 demonstrated this phenomenon in a series of patients with large rotator cuff tears who developed superior displacement of the humeral component and glenoid loosening.
The tendon to bone insertion site is a complex transitional region that links two very different ... more The tendon to bone insertion site is a complex transitional region that links two very different materials. The insertion site must transfer a complex loading environment effectively to prevent injury and provide proper joint function. In order to accomplish this load transfer effectively, the properties of the insertion site were hypothesized to vary along its length. The quasilinear viscoelastic (QLV) Model was used to determine biomechanical properties, polarized light analysis was used to quantitate collagen orientation (structure), and in situ hybridization was used to determine the expression of extracellular matrix genes (composition). All assays were performed at two insertion site locations: the tendon end of the insertion and the bony end of the insertion. Biomechanically, the apparent properties of peak strain, the coefficients (A and B ) that describe the elastic component of the QLV model, and one of the coefficients ( 7 , ) of the viscous component of the model were significantly higher, while another of the coefficients ( C ) of the viscous component was significantly lower at the tendon insertion compared to the bony insertion. The collagen was significantly more oriented at the tendon insertion compared to the bony insertion. Finally, collagen types 11, IX, and X, and aggrecan were localized only to the bony insertion, while decorin and biglycan were localized only to the tendon insertion. Thus, the tendon to bony insertion site varies dramatically along its length in terms of its viscoelastic properties, collagen structure, and extracellular matrix composition.
Rotator cuff tears of the shoulder are a common cause of pain and disability. The successful repa... more Rotator cuff tears of the shoulder are a common cause of pain and disability. The successful repair of rotator cuff tendon tears depends on the time from onset of injury to the time of surgical repair. However, the effect of time from injury to repair remains poorly understood. A rat model was used to investigate the supraspinatus tendon organizational and mechanical property changes that occur with time post-injury to understand the natural injury response in the absence of repair. It was hypothesized that increased time post-injury would result in increased detrimental changes to tendon organizational and mechanical properties. Tendons were detached at the insertion on the humerus without repair and the quantitative organizational and mechanical properties were analyzed at 1, 2, 4, 8, and 16 weeks post-detachment. Tendon detachment resulted in a dramatic decrease in mechanical properties initially followed by a progressive increase with time. The quantitative collagen fiber orientation results provided corroborating support to the mechanical property data. Based on similarities in histology and mechanical properties to rotator cuff tears in humans, the animal model presented here is promising for future investigations of the tendon's natural injury response in the absence of repair. r
Abstract This study focuses on the single-chain fragment variable (scFv) variant of the original ... more Abstract This study focuses on the single-chain fragment variable (scFv) variant of the original IgA-type antibody, recognizing the α2 C-terminal telopeptide (α2Ct) of human collagen I, designed to inhibit post-traumatic localized fibrosis via blocking the formation of collagen-rich deposits. We have demonstrated that the scFv construct expressed in yeast cells was able to fold into an immunoglobulin-like conformation, but it was prone to forming soluble aggregates. Functional assays, however, indicate that the scFv construct specifically binds to the α2Ct epitope and inhibits collagen fibril formation both in vitro and in a cell culture model representing tissues that undergo post-traumatic fibrosis. Thus, the presented study demonstrates the potential of the scFv variant to serve as an inhibitor of the excessive formation of collagen-rich fibrotic deposits, and it reveals certain limitations associated with the current stage of development of this antibody construct.
Six fresh frozen, human cadaver shoulders were evaluated for gross anatomic, magnetic resonance i... more Six fresh frozen, human cadaver shoulders were evaluated for gross anatomic, magnetic resonance imaging, and histologic abnormalities. The shoulders underwent routine magnetic resonance imaging with and without intraarticular Gadolinium using a standard surface shoulder coil. The shoulders were dissected in a systematic fashion to yield 18 anatomic specimens from the supraspinatus and infraspinatus tendon as well as the glenoid labrum. These specimens were studied histologically using hematoxylin and eosin and Goldner's trichrome stains. Gross anatomic and magnetic resonance image abnormalities of the rotator cuff corresponded to histologic changes consistent with tendon degeneration. However, there was a poor correlation between gross anatomic, magnetic resonance image, and histologic changes of degeneration in the glenoid labrum. In general, histologic degeneration was more severe than abnormalities seen either grossly or on magnetic resonance images.
Rotator cuff tears occur frequently and can cause significant pain and reduced shoulder function.... more Rotator cuff tears occur frequently and can cause significant pain and reduced shoulder function. A high percentage of patients are satisfied after surgical repair of rotator cuff tears, but a smaller percentage of patients with chronic tears continue to have pain and poor shoulder function. This may be partly attributable to an increase in the repair tension, the force required at repair to reappose the tendon to its original insertion site on the humerus. Increases in repair tension have been shown to occur for long-standing ruptures of the supraspinatus tendon, but the precise tension at various times after injury are unknown. Therefore, the objective of the current study was to determine the repair tension at various times after a rotator cuff tear. This was achieved by creating a full-thickness supraspinatus tendon tear in a rat model and measuring the mechanical characteristics of the musculotendinous unit at 0, 2, 4, 9, and 16 weeks after injury. The repair tension rapidly increased initially after injury followed by a progressive, but less dramatic, increase with additional time. These findings suggest that rotator cuff tears should be repaired early in the clinical setting. Future studies will investigate the effect of repair tension on tendon to bone healing after repair.
Background More elderly patients are becoming candidates for total shoulder arthroplasty with an ... more Background More elderly patients are becoming candidates for total shoulder arthroplasty with an increase in frequency of the procedure paralleling the rise in other total joint arthroplasties. Controversy still exists, however, regarding the perioperative morbidity of total joint arthroplasty in elderly patients, particularly those 80 years of age and older. Questions/purposes We asked whether perioperative complications and mortality, transfusion requirements, inpatient length of stay, and discharge disposition after total shoulder arthroplasty were similar in patients 80 years and older compared with those in younger patients.
Journal of shoulder and elbow surgery / American Shoulder and Elbow Surgeons ... [et al.], Jan 18, 2015
Reverse shoulder arthroplasty (RSA) has been Food and Drug Administration approved in the United ... more Reverse shoulder arthroplasty (RSA) has been Food and Drug Administration approved in the United States since 2004 but did not obtain a unique code until 2010. Therefore, the use of this popular procedure has yet to be reported. The purpose of this study was to examine the use and reimbursement of RSA compared with total shoulder arthroplasty (TSA) and shoulder hemiarthroplasty (SHA). We analyzed the 100% sample of the 2011 Medicare Part A claims data for patients aged 65 years or older. Patient demographic characteristics, diagnoses, provider information, reimbursements, and lengths of stay were extracted from the claims data. In 2011, a total of 31,002 shoulder arthroplasty procedures were performed; 37% were RSAs, 42% were TSAs, and 21% were SHAs. Osteoarthritis was the primary diagnosis code in 91% of TSAs, 37% of SHAs, and 45% of RSAs. A primary diagnosis of osteoarthritis with no secondary code for rotator cuff tear was found in 22% of patients undergoing RSA. The mean length ...
Journal of shoulder and elbow surgery / American Shoulder and Elbow Surgeons ... [et al.], Jan 13, 2015
Periprosthetic joint infection (PJI) is a major cause of morbidity after shoulder arthroplasty. P... more Periprosthetic joint infection (PJI) is a major cause of morbidity after shoulder arthroplasty. PJI epidemiology has not been well studied. We aimed to analyze the historical incidence, predisposing factors, and economic burden of PJI after shoulder arthroplasty in the United States. Primary shoulder arthroplasty patients were identified by the International Classification of Diseases, Ninth Revision, Clinical Modification codes 81.80 (total shoulder arthroplasty), 81.81 (hemiarthroplasty), and 81.88 (reverse arthroplasty) in the Nationwide Inpatient Sample from 2002 to 2011. PJI was identified by codes 80.01 (arthrotomy for device removal) and 996.66 (prosthetic infection). Multivariate logistic regression analysis was used to identify predisposing factors for PJI. PJI rate was 0.98% from 2002 to 2011 and did not vary significantly. Comorbidities associated with PJI were weight loss/nutritional deficiency (odds ratio [OR], 2.62; 95% confidence interval [CI], 1.53-4.51; P = .00047),...
Journal of shoulder and elbow surgery / American Shoulder and Elbow Surgeons ... [et al.], Jan 4, 2014
The incidence of failed rotator cuff repairs remains high, especially in the setting of massive t... more The incidence of failed rotator cuff repairs remains high, especially in the setting of massive tears or revision repairs. The purpose of this study was to evaluate patient outcomes and repair integrity after augmentation with the repair patch, a poly-l-lactide synthetic polymer. Sixteen consecutive patients with massive or recurrent rotator cuff tears underwent open repair with synthetic poly-l-lactide patch augmentation. Two patients required the patch to bridge defects, and 1 patient retore after a motor vehicle accident and had revision surgery at another institution. The 13 remaining patients were retrospectively evaluated from 1.2 to 1.7 years (average, 1.5 years) after surgery by PENN, American Shoulder and Elbow Surgeons, and Single Assessment Numeric Evaluation scores. Magnetic resonance imaging was used to examine the integrity of the repair at a minimum of 1 year of follow-up. The mean age was 57.3 years (42-68 years). Five patients (38%) had an intact rotator cuff at the...
Journal of shoulder and elbow surgery / American Shoulder and Elbow Surgeons ... [et al.], 2014
The introduction of the reverse shoulder arthroplasty has provided shoulder surgeons with more op... more The introduction of the reverse shoulder arthroplasty has provided shoulder surgeons with more options for the treatment of complex proximal humeral fractures in the elderly. Early reported results suggest that the average functional outcome may be better than hemiarthroplasty in certain patients and specific clinical scenarios. In addition, these results seem to be reached more quickly with less dependence on rehabilitation. The reverse prosthesis may be particularly useful in patients aged older than 70 years, especially those with severely comminuted fractures in osteopenic bone. These factors likely have a negative impact on the results of hemiarthroplasty and internal fixation. Despite the potential benefits of reverse arthroplasty for fracture, there is a significant learning curve with the use of this prosthesis, and it has its own set of complications. The surgeon must show appropriate judgment when selecting a reverse arthroplasty in the setting of a proximal humeral fractu...
We retrospectively reviewed 68 patients (70 shoulders) who underwent either open or arthroscopic ... more We retrospectively reviewed 68 patients (70 shoulders) who underwent either open or arthroscopic acromioplasty performed by a single surgeon (JPI) for chronic impingement syndrome in the presence of an intact rotator cuff. Group 1 consisted of 24 shoulders that had open acromioplasty and group 2 consisted of 46 shoulders that had arthroscopic acromioplasty. The minimum follow-up was 12 months for both groups. There was no statistical difference in mean postoperative shoulder scores between the operative groups. However, there were more excellent results in the open group as compared with the arthroscopic group (54.2% vs 41.9%, respectively). In addition, there was a higher percentage of poor results in group 2 as compared with group 1 (27.9% vs 16.6%, respectively). Arthroscopic acromioplasty was associated with shorter hospital stays and faster achievement of maximal pain relief as compared with open acromioplasty. Examination of postoperative radiographs often revealed subacromial calcifications. These calcifications were more frequent after arthroscopic acromioplasty and were associated with a worse result.
Hypothesis: This study evaluated the intra-rater and inter-rater correlation of 3 commonly used x... more Hypothesis: This study evaluated the intra-rater and inter-rater correlation of 3 commonly used x-ray image classifications and defined the clinical factors most correlated with a surgical recommendation for a hemiarthroplasty or a reverse total shoulder arthroplasty (RSA) for treatment of rotator cuff tear arthropathy (CTA). We hypothesized that specific radiographic criteria and clinical criteria would be most important and consistently used among experienced shoulder surgeons when determining the best surgical option for a particular patient. Methods: Four experienced orthopedic surgeons evaluated standard anteroposterior radiographs and the clinical examination of 37 shoulders with CTA. On each reading, they classified the grade of pathology using the Seebauer, Favard, and Hamada classifications. Using radiographic criteria alone, or with the clinical findings, each evaluator determined the recommended prosthetic treatment for each shoulder. Results: Intra-rater correlations for surgical recommendations using radiographic criteria ranged from 0.39 to 1.0 and improved in 3 of 4 evaluators when the clinical examination was included in the clinical decision. The inter-rater reliability using these same criteria were fair, at 0.32 for radiographic and .35 for radiographic and clinical data. The most significant radiographic factors associated with a surgical decision were the degree of humeral head superior migration and the escape of the humeral head from the coracoacromial arch. Clinical factors most associated with the decision for RSA were advanced age, loss of shoulder elevation, superior humeral head escape, and pseudoparalysis of the shoulder. Radiographic findings had a less significant effect on surgical recommendations when clinical factors were included. Conclusion: Clinical and radiographic criteria are needed for a decision for hemiarthroplasty or RSA in the treatment of CTA. A treatment algorithm based upon radiographic and clinical criteria is proposed. Level of evidence: Level III. Diagnostic Agreement Study With Nonconsecutive Patients.
Although rotator cuff repair is often successful at relieving pain, the repaired insertion site f... more Although rotator cuff repair is often successful at relieving pain, the repaired insertion site frequently fails. Mechanical properties of the repair improved when the shoulder was immobilized in an animal model, but joint stiffness and range of motion were not evaluated. The objective of this study was to measure rotational mechanics before and after shoulders were immobilized after cuff injury and repair, not immobilized after cuff injury and repair, and immobilized without injury and repair. Humeral rotation was significantly less 4 and 8 weeks after injury and repair but did not decrease significantly when the injured and repaired shoulder was immobilized. Rotational stiffness increased significantly 4 and 8 weeks after injury and repair and was significantly greater at 4, but not 8, weeks when the injured and repaired shoulders were immobilized. This study demonstrated that the increase in joint stiffness caused by immobilizing an injured and repaired shoulder was transient and, therefore, does not outweigh the long-term benefits of immobilization on improved tendon to bone healing. (J Shoulder Elbow Surg 2008;17:108S-113S.)
Scapular notching in reverse shoulder arthroplasty appears to be a multifactorial problem related... more Scapular notching in reverse shoulder arthroplasty appears to be a multifactorial problem related to both implant and patient factors. There are well-established guidelines for implant position. Recent cadaveric studies have illustrated anatomic factors that need further consideration. Scapular neck length and inferior glenoid tubercle morphology may be major factors predicting scapular notching. From 2 institutions, we reviewed 3 years of patient radiographs for reverse shoulder arthroplasty, including all reverse shoulder arthroplasties at least 12 months from surgery. We used true anterior-posterior radiographs, both preoperatively and postoperatively, and focused on the "ideal" positioning of the glenosphere: at or below the inferior margin of the glenoid, and neutral or slight inferior tilt. Radiographs were reviewed by 2 independent surgeons. Glenoid articular surface height was measured along with scapular neck length and notching presence. Of 64 sets of radiographs reviewed, 50 met inclusion criteria. Notching was present in only 25 (50%) of the sets. The mean scapular neck length was 8.9 mm with a neck:surface ratio of 0.23 in the notching present group and 12.1 mm with a neck:surface ratio of 0.32 in the notching absent group. Significance was reached with both scapular neck length and neck:surface ratio (P = .0012 and P = .0006, respectively). There is a high degree of significance that patient anatomy does play a role in the occurrence of notching. Surgeons may consider lateralizing the glenosphere in patients with a scapular neck length of less than 9 mm measured on a true anteroposterior radiograph. Anatomy study, imaging.
We retrospectively reviewed 32 patients who underwent glenoid revision surgery after total should... more We retrospectively reviewed 32 patients who underwent glenoid revision surgery after total shoulder arthroplasty to compare the results of revision total shoulder arthroplasty with those of revision hemiarthroplasty and to identify factors associated with poor results after revision shoulder arthroplasty for glenoid component loosening. Results were reviewed at a mean follow-up of 4 years (range, 2-8 years). Glenoid reimplantation resulted in significant pain relief (P Ͻ .0001), improvement in American Shoulder and Elbow Surgeons (ASES) score (P Ͻ .02), and external rotation (24°to 44°, P Ͻ .004). Revision to a hemiarthroplasty also resulted in significant pain relief (P Ͻ .01) and improvement in ASES score (P Ͻ .05). For the treatment of glenoid loosening without glenohumeral instability, both reimplantation of a glenoid component and revision to a hemiarthroplasty improved function, satisfaction, and level of pain. Reimplantation of a new glenoid component offered greater improvements in pain (P Ͻ .008) and external rotation (increase of 20°v ersus 3°, P Ͻ .03) compared with hemiarthroplasty. For patients with preoperative glenohumeral instability, revision surgery did not improve motion, function, or pain significantly. Risk factors associated with a poor outcome after revision arthroplasty included persistent glenohumeral instability, rotator cuff tears, and malunion of the greater tuberosity. (J Shoulder Elbow Surg 2007;16: 706-716.) Symptomatic loosening of the glenoid component is one of the most common complications associated with total shoulder arthroplasty (TSA). 7,28,38 Although the incidence of component loosening requiring revision surgery is low (0%-4.2%), this complication represents approximately 25% of all complications related to TSA. 7, Similarly, few reports exist in the literature regarding the outcome of revision surgery for glenoid component loosening. Etiologic factors associated with aseptic glenoid component loosening include irreparable tears of the rotator cuff, component malposition, tuberosity malunion, and glenohumeral instability. Each of these factors can independently or in combination lead to eccentric loads borne on the glenoid component. Eccentric load increases stresses at the bonecement interface and increases micro motion of the glenoid component, which can lead to component loosening. Franklin et al 11 demonstrated this phenomenon in a series of patients with large rotator cuff tears who developed superior displacement of the humeral component and glenoid loosening.
The tendon to bone insertion site is a complex transitional region that links two very different ... more The tendon to bone insertion site is a complex transitional region that links two very different materials. The insertion site must transfer a complex loading environment effectively to prevent injury and provide proper joint function. In order to accomplish this load transfer effectively, the properties of the insertion site were hypothesized to vary along its length. The quasilinear viscoelastic (QLV) Model was used to determine biomechanical properties, polarized light analysis was used to quantitate collagen orientation (structure), and in situ hybridization was used to determine the expression of extracellular matrix genes (composition). All assays were performed at two insertion site locations: the tendon end of the insertion and the bony end of the insertion. Biomechanically, the apparent properties of peak strain, the coefficients (A and B ) that describe the elastic component of the QLV model, and one of the coefficients ( 7 , ) of the viscous component of the model were significantly higher, while another of the coefficients ( C ) of the viscous component was significantly lower at the tendon insertion compared to the bony insertion. The collagen was significantly more oriented at the tendon insertion compared to the bony insertion. Finally, collagen types 11, IX, and X, and aggrecan were localized only to the bony insertion, while decorin and biglycan were localized only to the tendon insertion. Thus, the tendon to bony insertion site varies dramatically along its length in terms of its viscoelastic properties, collagen structure, and extracellular matrix composition.
Rotator cuff tears of the shoulder are a common cause of pain and disability. The successful repa... more Rotator cuff tears of the shoulder are a common cause of pain and disability. The successful repair of rotator cuff tendon tears depends on the time from onset of injury to the time of surgical repair. However, the effect of time from injury to repair remains poorly understood. A rat model was used to investigate the supraspinatus tendon organizational and mechanical property changes that occur with time post-injury to understand the natural injury response in the absence of repair. It was hypothesized that increased time post-injury would result in increased detrimental changes to tendon organizational and mechanical properties. Tendons were detached at the insertion on the humerus without repair and the quantitative organizational and mechanical properties were analyzed at 1, 2, 4, 8, and 16 weeks post-detachment. Tendon detachment resulted in a dramatic decrease in mechanical properties initially followed by a progressive increase with time. The quantitative collagen fiber orientation results provided corroborating support to the mechanical property data. Based on similarities in histology and mechanical properties to rotator cuff tears in humans, the animal model presented here is promising for future investigations of the tendon's natural injury response in the absence of repair. r
Abstract This study focuses on the single-chain fragment variable (scFv) variant of the original ... more Abstract This study focuses on the single-chain fragment variable (scFv) variant of the original IgA-type antibody, recognizing the α2 C-terminal telopeptide (α2Ct) of human collagen I, designed to inhibit post-traumatic localized fibrosis via blocking the formation of collagen-rich deposits. We have demonstrated that the scFv construct expressed in yeast cells was able to fold into an immunoglobulin-like conformation, but it was prone to forming soluble aggregates. Functional assays, however, indicate that the scFv construct specifically binds to the α2Ct epitope and inhibits collagen fibril formation both in vitro and in a cell culture model representing tissues that undergo post-traumatic fibrosis. Thus, the presented study demonstrates the potential of the scFv variant to serve as an inhibitor of the excessive formation of collagen-rich fibrotic deposits, and it reveals certain limitations associated with the current stage of development of this antibody construct.
Six fresh frozen, human cadaver shoulders were evaluated for gross anatomic, magnetic resonance i... more Six fresh frozen, human cadaver shoulders were evaluated for gross anatomic, magnetic resonance imaging, and histologic abnormalities. The shoulders underwent routine magnetic resonance imaging with and without intraarticular Gadolinium using a standard surface shoulder coil. The shoulders were dissected in a systematic fashion to yield 18 anatomic specimens from the supraspinatus and infraspinatus tendon as well as the glenoid labrum. These specimens were studied histologically using hematoxylin and eosin and Goldner's trichrome stains. Gross anatomic and magnetic resonance image abnormalities of the rotator cuff corresponded to histologic changes consistent with tendon degeneration. However, there was a poor correlation between gross anatomic, magnetic resonance image, and histologic changes of degeneration in the glenoid labrum. In general, histologic degeneration was more severe than abnormalities seen either grossly or on magnetic resonance images.
Rotator cuff tears occur frequently and can cause significant pain and reduced shoulder function.... more Rotator cuff tears occur frequently and can cause significant pain and reduced shoulder function. A high percentage of patients are satisfied after surgical repair of rotator cuff tears, but a smaller percentage of patients with chronic tears continue to have pain and poor shoulder function. This may be partly attributable to an increase in the repair tension, the force required at repair to reappose the tendon to its original insertion site on the humerus. Increases in repair tension have been shown to occur for long-standing ruptures of the supraspinatus tendon, but the precise tension at various times after injury are unknown. Therefore, the objective of the current study was to determine the repair tension at various times after a rotator cuff tear. This was achieved by creating a full-thickness supraspinatus tendon tear in a rat model and measuring the mechanical characteristics of the musculotendinous unit at 0, 2, 4, 9, and 16 weeks after injury. The repair tension rapidly increased initially after injury followed by a progressive, but less dramatic, increase with additional time. These findings suggest that rotator cuff tears should be repaired early in the clinical setting. Future studies will investigate the effect of repair tension on tendon to bone healing after repair.
Background More elderly patients are becoming candidates for total shoulder arthroplasty with an ... more Background More elderly patients are becoming candidates for total shoulder arthroplasty with an increase in frequency of the procedure paralleling the rise in other total joint arthroplasties. Controversy still exists, however, regarding the perioperative morbidity of total joint arthroplasty in elderly patients, particularly those 80 years of age and older. Questions/purposes We asked whether perioperative complications and mortality, transfusion requirements, inpatient length of stay, and discharge disposition after total shoulder arthroplasty were similar in patients 80 years and older compared with those in younger patients.
Journal of shoulder and elbow surgery / American Shoulder and Elbow Surgeons ... [et al.], Jan 18, 2015
Reverse shoulder arthroplasty (RSA) has been Food and Drug Administration approved in the United ... more Reverse shoulder arthroplasty (RSA) has been Food and Drug Administration approved in the United States since 2004 but did not obtain a unique code until 2010. Therefore, the use of this popular procedure has yet to be reported. The purpose of this study was to examine the use and reimbursement of RSA compared with total shoulder arthroplasty (TSA) and shoulder hemiarthroplasty (SHA). We analyzed the 100% sample of the 2011 Medicare Part A claims data for patients aged 65 years or older. Patient demographic characteristics, diagnoses, provider information, reimbursements, and lengths of stay were extracted from the claims data. In 2011, a total of 31,002 shoulder arthroplasty procedures were performed; 37% were RSAs, 42% were TSAs, and 21% were SHAs. Osteoarthritis was the primary diagnosis code in 91% of TSAs, 37% of SHAs, and 45% of RSAs. A primary diagnosis of osteoarthritis with no secondary code for rotator cuff tear was found in 22% of patients undergoing RSA. The mean length ...
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Papers by Gerald Williams