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Background: Following revision shoulder arthroplasty, postoperative antibiotics are selected before the results of intraoperative cultures become available. We determined infection-free survival, revision-free survival, complications, and patient-reported outcomes for patients selected to receive oral or intravenous (IV) antibiotics after revision arthroplasty., Methods: This study included 92 patients who had revision shoulder arthroplasty. IV antibiotics were administered if the surgeon had a high index of suspicion for infection, and oral antibiotics were given if there was a low suspicion. Antibiotic therapy was modified based on intraoperative culture results. Patient-reported outcomes and adverse events were documented at a mean of 4.1 years., Results: In selecting antibiotic therapy, surgeons correctly predicted the presence or absence of multiple positive cultures of specimens from the revision surgery in 72% of the 92 cases. Subsequent re-revision surgery was required in 17 (18%) of the patients; 8 of these 17 patients had ≥2 positive cultures at re-revision. Patients who initially received IV antibiotics and those who initially received oral antibiotics had similar revision-free (p = 0.202) and infection-free (p = 0.155) survivorship. Patients requiring a change from oral to IV antibiotics based on positive cultures had similar survivorship compared with those initially treated with IV antibiotics. The IV and oral antibiotic groups had similar postoperative Simple Shoulder Test (SST), American Shoulder and Elbow Surgeons (ASES), and satisfaction scores. Patients receiving IV antibiotics had a higher rate of antibiotic-related adverse events., Conclusions: Post-revision antibiotic therapy was associated with an infection-free survival rate of 91% at a mean of >4 years of follow-up. Infection-free survival, revision-free survival, and patient-reported outcomes were similar in high-risk patients placed on IV antibiotics and low-risk patients placed on oral antibiotics. Further study is needed to define the indications for IV or oral antibiotics after revision arthroplasty., Level of Evidence: Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence., Competing Interests: Disclosure: The Disclosure of Potential Conflicts of Interest forms are provided with the online version of the article (http://links.lww.com/JBJS/G783)., (Copyright © 2021 by The Journal of Bone and Joint Surgery, Incorporated.)

Background: Publications regarding anatomic total shoulder arthroplasty (TSA) have consistently reported that they provide significant improvement for patients with glenohumeral arthritis. New TSA technologies that have been introduced with the goal of further improving these outcomes include preoperative computed tomography (CT) scans, 3-dimensional preoperative planning, patient-specific instrumentation, stemless and short-stemmed humeral components, as well as metal-backed, hybrid, and augmented glenoid components. The benefit of these new technologies in terms of patient-reported outcomes is unknown., Methods: We reviewed 114 articles presenting preoperative and postoperative values for commonly used patient-reported metrics. The results were analyzed to determine whether patient outcomes have improved over the 20 years during which new technologies became available., Results: The analysis did not identify evidence that the results of TSA were statistically or clinically improved over the 2 decades of study or that any of the individual technologies were associated with significant improvement in patient outcomes., Conclusions: Additional research is required to document the clinical value of these new technologies to patients with glenohumeral arthritis., Level of Evidence: Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence., Competing Interests: Disclosure: The authors indicated that no external funding was received for any aspect of this work. On the Disclosure of Potential Conflicts of Interest forms, which are provided with the online version of the article, one or more of the authors checked “yes” to indicate that the author had a relevant financial relationship in the biomedical arena outside the submitted work and “yes” to indicate that the author had other relationships or activities that could be perceived to influence, or have the potential to influence, what was written in this work (http://links.lww.com/JBJS/G350)., (Copyright © 2021 by The Journal of Bone and Joint Surgery, Incorporated.)

Background: When performing revision shoulder arthroplasty, surgeons do not have access to the results of intraoperative culture specimens and will administer empiric antibiotics to cover for the possibility of deep infection until the culture results are finalized. The purpose of this study was to report the factors associated with the initiation, modification, and adverse events of 2 different postoperative antibiotic protocols in a series of revision shoulder arthroplasties., Methods: In this study, 175 patients undergoing revision shoulder arthroplasty were treated with either a protocol of intravenous (IV) antibiotics if there was a high index of suspicion for infection or a protocol of oral antibiotics if the index of suspicion was low. Antibiotics were withdrawn if cultures were negative and were modified as indicated if the cultures were positive. Antibiotic course, modification, and adverse effects to antibiotic administration were documented., Results: On univariate analysis, factors significantly associated with the initiation of IV antibiotics were male sex (p < 0.001), history of infection (p < 0.001), intraoperative humeral loosening (p = 0.003), and membrane formation (p < 0.001). On multivariate analysis, male sex (p = 0.003), history of infection (p = 0.003), and membrane formation (p < 0.001) were found to be independent predictors of the initiation of IV antibiotics. On the basis of preoperative and intraoperative characteristics, surgeons anticipated the culture results in 75% of cases, and modification of antibiotic therapy was required in 25%. The modification from oral to IV antibiotics due to positive culture results was made significantly more often in male patients (p < 0.001). Adverse effects of antibiotic administration occurred in 19% of patients. The rates of complications were significantly lower in the patients treated with oral antibiotics and a shorter course of antibiotics (p < 0.001)., Conclusions: Complications associated with antibiotic administration after revision shoulder arthroplasty are not infrequent and are more common in patients whose initial protocol is IV antibiotics. Further study is needed to balance the effectiveness and risks of post-revision antibiotic treatment given the frequency of antibiotic-related complications., Level of Evidence: Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

We previously reported the results at an average of 4.5 years after treatment of 176 patients with the ream-and-run arthroplasty. In the present study, we present the patient self-reported functional outcomes and clinical implant survival of the original cohort at a mean of 10 years (range, 5 to 16 years). Twenty-eight (16%) of the 176 patients had a subsequent procedure, 11 (6%) died, and 30 (17%) had <5 years of follow-up. The Simple Shoulder Test (SST) score at the time of the latest follow-up was a median of 11 points (interquartile range, 9 to 12 points) and a mean (and standard deviation) of 10 ± 2.6 points, out of a possible 12 points. The present study demonstrates that the improvement in function and comfort derived from the ream-and-run procedure can be sustained at the time of mid-term follow-up., Level of Evidence: Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Background: The ream-and-run procedure can provide improvement in shoulder function and comfort for selected patients with primary glenohumeral arthritis who wish to avoid a prosthetic glenoid component. The purpose of this study was to evaluate factors associated with medialization of the humeral head after this procedure as well as the relationship of medialization to the clinical outcome., Methods: We collected patient, shoulder, and procedure characteristics along with Simple Shoulder Test (SST) scores before surgery and at the time of follow-up. Medialization was determined by comparing the position of the humeral head prosthesis in relation to the scapula on postoperative baseline radiographs made within 6 weeks after surgery with that on comparable follow-up radiographs made ≥18 months after surgery., Results: Two-year clinical outcomes were available for 101 patients (95% were male). Comparable radiographs at postoperative baseline and follow-up evaluations were available for 50 shoulders. For all patients, the mean SST score (and standard deviation) increased from 4.9 ± 2.8 preoperatively to 10.3 ± 2.4 at the latest follow-up (p < 0.001). Significant clinical improvement was observed for glenoid types A2 and B2. Shoulders with a type-A2 glenoid morphology, with larger preoperative scapular body-glenoid angles, and with lower preoperative SST scores, were associated with the greatest clinical improvement. Clinical outcome was not significantly associated with the amount of medialization., Conclusions: The ream-and-run procedure can be an effective treatment for advanced primary glenohumeral osteoarthritis in active patients. Further study will be necessary to determine whether medialization affects the clinical outcome with follow-up of >2 years., Level of Evidence: Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Background: Assessment of function is the cornerstone of clinical shoulder research. This purpose of this study was to answer 3 relevant questions: How does subjective patient assessment of shoulder function correlate with objectively measured active shoulder range of motion? What is the difference in active motion between shoulders that can and those that cannot be used to perform each of the functions of the Simple Shoulder Test (SST)? Does the relationship between subjective and objective assessment of shoulder function differ between male and female patients?, Methods: We analyzed the relationship between objective range-of-motion measurements recorded by the observer-independent Kinect motion capture system and SST patient self-assessments of shoulder function of 74 male and 30 female patients with osteoarthritis., Results: There was poor correlation between objective measurements of active abduction and total SST scores of osteoarthritic shoulders of patients seen before shoulder surgery: the coefficients of determination (R) were 0.29 for the osteoarthritic shoulders of women and 0.25 for those of men. The relationships between active abduction and total SST score were closer for the contralateral shoulders (R = 0.54 for women and R = 0.46 for men). The difference in active abduction between the osteoarthritic shoulders that allowed and those that did not allow the patient to perform the individual SST functions was significant (p < 0.05) for only 4 of the 12 functions in the female group and 5 of 12 in the male group because of the highly variable relationship between self-assessed function and active abduction. In contrast, when the contralateral shoulders were assessed, this difference was found to be significant for 10 of the 12 functions in the female group and all 12 of the functions in the male group. The relationship between objective motion and subjective function did not differ significantly between male and female subjects., Conclusions: The self-assessed function of osteoarthritic shoulders of women and men is only partially determined by the active range of abduction. Both subjective and objective measurements are important in characterizing the clinical status of shoulders. Studies of treatment outcomes should include separate assessments of these 2 complementary aspects of shoulder function., Level of Evidence: Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Background: Propionibacterium is commonly recovered from explants or surrounding tissues in revision shoulder arthroplasty. Rather than attempting to differentiate a true infection from a false-positive result on the basis of the number of positive cultures, we characterized the amount of these bacteria in each specimen and shoulder., Methods: The study included 137 revision shoulder arthroplasties from which a minimum of 4 specimens had been submitted for culture and at least 1 was positive for Propionibacterium. Standard microbiology procedures were used to assign a semiquantitative value (0.1, 1, 2, 3, or 4), called the Specimen Propi Value, to the amount of growth in each specimen. The sum of the Specimen Propi Values for each shoulder was defined as the Shoulder Propi Score, which was then divided by the total number of specimens to calculate the Average Shoulder Propi Score., Results: The number and percentage of positive specimen-specific cultures (of material obtained from the stem explant, head explant, glenoid explant, humeral membrane, collar membrane, other soft tissue, fluid, or other) per shoulder ranged from 1 to 6 and 14% to 100%. A high percentage of specimens (mean, 43%; median, 50%) from the culture-positive shoulders showed no growth. Only 32.6% of the fluid cultures were positive in comparison with 66.5% of the soft-tissue cultures and 55.6% of the cultures of explant specimens. The average Specimen Propi Value (and standard deviation) for fluid specimens (0.35 ± 0.89) was significantly lower than those for the soft-tissue (0.92 ± 1.50) and explant (0.66 ± 0.90) specimens (p < 0.001). The Shoulder Propi Score was significantly higher in men (3.56 ± 3.74) than in women (1.22 ± 3.11) (p < 0.001). Similarly, men had a significantly higher Average Shoulder Propi Score (0.53 ± 0.51) than women (0.19 ± 0.43) (p < 0.001)., Conclusions: This investigation suggests that Propionibacterium is unevenly distributed within culture-positive revised shoulders. As a result, the specimen number and source (explant, soft tissue, or fluid) have major influences on the culture results for a revised shoulder arthroplasty. We found no evidence that suggested useful threshold values for defining a true infection., Level of Evidence: Diagnostic Level III. See Instructions for Authors for a complete description of levels of evidence.

Background: Revision shoulder arthroplasties are often culture-positive for Propionibacterium. This study tests the hypothesis that the functional outcomes of revising Propionibacterium culture-positive failed arthroplasties with a single-stage revision and immediate antibiotic therapy are not inferior to the clinical outcomes of revising failed shoulder arthroplasties that are not culture-positive., Methods: Fifty-five shoulders without obvious clinical evidence of infection had a single-stage revision arthroplasty. The patient self-assessed functional outcomes for shoulders with ≥2 positive cultures for Propionibacterium (the culture-positive group) were compared with shoulders with no positive cultures or only 1 positive culture (the control group)., Results: The culture-positive group had 89% male patients, with a mean age (and standard deviation) of 63.5 ± 7.2 years. The mean Simple Shoulder Test (SST) scores for the 27 culture-positive shoulders improved from 3.2 ± 2.8 points before the surgical procedure to 7.8 ± 3.3 points at a mean follow-up of 45.8 ± 11.7 months after the surgical procedure (p < 0.001), a mean improvement of 49% of the maximum possible improvement. The control group had 39% male patients, with a mean age of 67.1 ± 8.1 years. The mean SST scores for the 28 control shoulders improved from 2.6 ± 1.9 points preoperatively to 6.1 ± 3.4 points postoperatively at a mean follow-up of 49.6 ± 11.8 months (p < 0.001), a mean improvement of 37% of the maximum possible improvement. Subsequent procedures for persistent pain or stiffness were required in 3 patients (11%) in the culture-positive group and in 3 patients (11%) in the control group; none of the revisions were culture-positive. Fourteen patients reported side effects to antibiotics., Conclusions: Clinical outcomes after single-stage revision for Propionibacterium culture-positive shoulders were at least as good as the outcomes in revision procedures for control shoulders. Two-stage revision procedures may not be necessary in the management of these cases. Patients should be educated with regard to potential antibiotic side effects., Level of Evidence: Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

➤ Propionibacterium is a slow-growing gram-positive rod that is part of the normal skin microbiome but can be found on culture of specimens from a large number of patients having revision shoulder arthroplasty performed for pain, stiffness, and component loosening. ➤ Propionibacterium infections do not present with obvious signs of infection, such as swelling, erythema, drainage, or tenderness, but rather are of the so-called stealth type, presenting with unexplained pain, stiffness, or component loosening months to years after the index arthroplasty. ➤ Not all propionibacteria are the same: certain subtypes of Propionibacterium are enriched with virulence factors that may enhance deep infection. ➤ Because propionibacteria typically reside in the pilosebaceous glands of the oily skin of the chest and back, standard surgical skin preparation solutions and even perioperative intravenous antibiotics are often inadequate at sterilizing the incision site; therefore, other prophylactic measures such as meticulous implant handling to avoid contact with dermal structures need to be considered. ➤ Recovery of Propionibacterium from the surgical wounds requires that multiple specimens for culture be taken from different areas of the shoulder to reduce sampling error, and cultures should be held for two weeks on multiple culture media. ➤ Future research efforts can be focused on reducing the risk of implant infection and point-of-care methods for identifying Propionibacterium infections., (Copyright © 2016 by The Journal of Bone and Joint Surgery, Incorporated.)

Background: Increased length of hospital stay, hospital readmission, and revision surgery are adverse outcomes that increase the cost of elective orthopaedic procedures, such as shoulder arthroplasty. Awareness of the factors related to these adverse outcomes will help surgeons and medical centers design strategies for minimizing their occurrence and for managing their associated costs., Methods: We analyzed data from the New York Statewide Planning and Research Cooperative System on 17,311 primary shoulder arthroplasties performed from 1998 to 2011 to identify factors associated with extended lengths of hospitalization after surgery, readmission within ninety days, and surgical revision., Results: The factors associated with each of these three adverse outcomes were different. Longer lengths of hospital stay were associated with female sex, advanced patient age, Medicaid insurance, comorbidities, fracture as the diagnosis for arthroplasty, higher hospital case volumes, and lower surgeon case volumes. Readmission was associated with advanced patient age and medical comorbidities. The most common diagnoses for readmission within ninety days were fluid and electrolyte imbalance (28%), acute pulmonary problems (21%), cardiac arrhythmia (20%), heart failure (15%), acute myocardial infarction (10%), and urinary tract infection (10%). Revision was associated with younger patient age and osteoarthritis or traumatic arthritis. The most common diagnoses at the time of revision surgery were unspecified mechanical complications of the implant (60%), shoulder pain (18%), dislocation of the prosthetic joint (12%), component loosening (10%), a broken prosthesis (8%), a cuff tear (7%), and infection (7%)., Conclusions: A small number of easily identified characteristics (sex, age, race, insurance type, comorbidities, diagnosis, and provider case volumes) were significantly associated with longer lengths of stay, readmission, and revision surgery. Consideration of these factors and their effects may guide efforts to improve patient safety and to manage the costs associated with these adverse outcomes., (Copyright © 2015 by The Journal of Bone and Joint Surgery, Incorporated.)

Background: Propionibacterium acnes, which normally resides in the skin, is known to play a role in surgical site infection in orthopaedic surgery. Studies have suggested a persistence of propionibacteria on the skin surface, with rates of positive cultures ranging from 7% to 29% after surgical preparation. However, as Propionibacterium organisms normally reside in the dermal layer, these studies may underestimate the true prevalence of propionibacteria after surgical skin preparation. We hypothesized that, after surgical skin preparation, viable Propionibacterium remains in the dermis at a much higher rate than previously reported., Methods: Ten healthy male volunteers underwent skin preparation of the upper back with ChloraPrep (2% chlorhexidine gluconate and 70% isopropyl alcohol). Two 3-mm dermal punch biopsy specimens were obtained through the prepared skin and specifically cultured for P. acnes., Results: Seven volunteers had positive findings for Propionibacterium on dermal cultures after ChloraPrep skin preparation. The average time to positive cultures was 6.78 days., Conclusions: This study found that Propionibacterium persists in the dermal tissue even after surface skin preparation with ChloraPrep. The 70% rate of persistence of propionibacteria after skin preparation is substantially higher than previously reported., Clinical Relevance: Propionibacteria are increasingly discussed as having an association with infection, implant failure, and degenerative disease. This study confirms the possibility that the dermal layer of skin may be the source of the bacteria., (Copyright © 2014 by The Journal of Bone and Joint Surgery, Incorporated.)

Background: Glenoid component failure is a common and serious complication of total shoulder arthroplasty. The purpose of this study was to evaluate published evidence on whether metal backing lessens the rate of glenoid component failure., Methods: A comprehensive systematic review yielded twenty-one studies on radiolucency, radiographic failure, and revision after arthroplasty with metal-backed glenoid components and twenty-three studies with all-polyethylene components. Our analysis included data on 1571 metal-backed and 3035 all-polyethylene components. The mean duration of follow-up was 5.8 years in the studies with metal-backed components and 7.3 years with all-polyethylene components., Results: All-polyethylene components had a 42.5% rate of radiolucency compared with 34.9% for metal-backed components (p = 0.0026) and a 21.1% rate of radiographic loosening or failure compared with 16.8% for metal-backed components (p = 0.0005). However, the rate of revision was more than three times higher with metal-backed components (14.0%) than with all-polyethylene components (3.8%, p < 0.0001). Although 77% of the revisions of all-polyethylene components were for loosening, 62% of the revisions of metal-backed components were for other reasons, such as component fracture, screw breakage, component dissociation, polyethylene wear, metal wear, and rotator cuff tear (p < 0.0001)., Conclusions: The published evidence indicates that metal-backed glenoid components require revision at a significantly higher rate and for different reasons in comparison with all-polyethylene components., Level of Evidence: Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence., (Copyright © 2014 by The Journal of Bone and Joint Surgery, Incorporated.)

Background: Although glenoid component failure is one of the most common complications of anatomic total shoulder arthroplasty, substantial evidence from the recent published literature is lacking regarding the temporal trend in the rate of this complication and the risk factors for its occurrence., Methods: We conducted a systematic review and identified twenty-seven articles presenting data on glenoid component failure rates that met the inclusion criteria. These articles represented data from 3853 total shoulder arthroplasties performed from 1976 to 2007., Results: Asymptomatic radiolucent lines occurred at a rate of 7.3% per year after the primary shoulder replacement. Symptomatic glenoid loosening occurred at 1.2% per year, and surgical revision occurred at 0.8% per year. There was no significant evidence that the rate of symptomatic loosening has diminished over time. Keeled components had greater rates of asymptomatic radiolucent lines compared with pegged components in side-by-side comparison studies. However, as a result of wide variability in outcomes reporting, only sex, Walch class, and diagnosis were significantly associated with the risk of glenoid component failure in the overall analysis., Conclusions: This is the first systematic review of the published evidence on glenoid component failure. Although the authors of individual articles proposed various risk factors for glenoid component failure, many of these relationships were not significant in the present study. A consistent methodological approach to future investigations is likely to improve the quality of the evidence on which patients, techniques, and prostheses are selected for total shoulder arthroplasty.

Background: To explore the origin of Propionibacterium in surgical wounds and to suggest an optimized strategy for culturing this organism at the time of revision surgery, we studied the presence of this organism on the skin and in the surgical wounds of patients who underwent revision arthroplasty for reasons other than apparent infection., Methods: Specimens were cultured in broth and on aerobic and anaerobic media. The presence and degree of positivity of Propionibacterium cultures were correlated with sex. The results of dermal and deep cultures were correlated. Times to positivity and the yields of each media type and specimen source were investigated., Results: Propionibacterium grew in twenty-three of thirty cultures of specimens obtained preoperatively from the unprepared epidermis over the area where a skin incision was going to be made for a shoulder arthroplasty; males had a greater average degree of positivity than females (p &lt; 0.002). Twelve of twenty-one male subjects and zero of twenty female subjects who had cultures of dermal specimens obtained during revision shoulder arthroplasty had positive findings for Propionibacterium (p = 0.0001). Twelve of twenty male subjects and only one of twenty female subjects had positive deep cultures (p = 0.0004). The positivity of dermal cultures for Propionibacterium was significantly associated with the positivity of deep cultures for this organism (p = 0.0001). If Propionibacterium was present in deep tissues, it was likely that it would be recovered by culture if four different specimens were obtained and cultured for a minimum of seventeen days on three different media: aerobic, anaerobic, and broth., Conclusions: Because the surgical incision of dermal sebaceous glands may be a source of Propionibacterium in deep wounds, strategies for minimizing the risk of Propionibacterium infections may need to be directed at minimizing the contamination of surgical wounds from these bacteria residing in rather than on the skin. Obtaining at least four specimens, observing them for seventeen days, and using three types of culture media optimize the recovery of Propionibacterium at the time of revision surgery.

Background: Glenohumeral chondrolysis is the irreversible destruction of previously normal articular cartilage, occurring most commonly after shoulder surgery in young individuals. The reported incidence of this complication has risen rapidly since the early 2000s. As chondrolysis cannot be reversed, its occurrence can only be prevented by establishing and avoiding its causes., Methods: We analyzed all published cases of glenohumeral chondrolysis, including the relevant published laboratory data, to consolidate the available evidence on the causation of this complication by the postoperative intra-articular infusion of local anesthetic via a pain pump., Results: Analysis of the published evidence demonstrated a causal relationship between the infusion of local anesthetic and the development of glenohumeral chondrolysis. The risk of this complication in shoulders receiving intra-articular infusions via a pain pump was significantly greater with higher doses of local anesthetic: twenty of forty-eight shoulders receiving high-flow infusions developed chondrolysis, whereas only two of twenty-five shoulders receiving low-flow infusions developed this complication (p = 0.0029). Eleven of twenty-two shoulders receiving 0.5% bupivacaine developed chondrolysis, whereas none of six shoulders receiving 0.25% bupivacaine developed this complication (p = 0.05). Of twenty-two shoulders infused with 0.5% bupivacaine, the eleven that developed chondrolysis had a mean pain pump delivery volume of 377 mL, whereas the eleven that did not develop chondrolysis had a mean volume of 187 mL (p = 0.003). Among shoulders in which an intra-articular pain pump was used, the risk of chondrolysis was significantly greater when suture anchors were placed in the glenoid for labral repair (p < 0.001)., Conclusions: The published evidence indicates that the preponderance of cases of glenohumeral chondrolysis can be prevented by the avoidance of the intra-articular infusion of local anesthetic via a pain pump.

Background: There is growing concern regarding conflicts of interest in orthopaedic research and education. Because of their potential influence on orthopaedic practice, conflicts of interest among participants in the educational programs of the American Academy of Orthopaedic Surgeons (AAOS) are of particular interest., Methods: We analyzed the voluntarily disclosed conflicts of interest listed in the Final Program of the 2011 Annual Meeting of the AAOS for the relevant program committees as well as for presentations in the disciplines of pediatric orthopaedic surgery, spine, and sports medicine/arthroscopy., Results: Conflicts of interest were disclosed by participants for each of the program committees and for over 75% of the presentations. Conflicts of interest were disclosed for 100% of the featured symposia, 80% of the scientific exhibits, 76% of the podium presentations, and 75% of the posters. Over half (53%) of the disclosures were for paid consultancy, 51% were for research support for the principal investigator, 41% were for paid presentations, 39% were for royalties, and 39% were for stock. The highest number of disclosures for an individual author was thirty-seven. The number of disclosures per author was significantly (p &lt; 0.001) correlated to the number of presentations per author. Disclosures were associated with 379 different companies; relationships with a relatively small number (twenty-six, 7%) of these companies were listed in the disclosures for 67% of the presentations., Conclusions: Voluntarily disclosed conflicts of interest were common at the 2011 AAOS Annual Meeting, especially for the featured symposia. In view of the previously documented frequency of undisclosed conflicts of interest, as well as the previously documented effects of conflicts of interest on research design, conduct, and conclusion, it may be time to consider improved strategies for ensuring the accuracy and completeness of disclosure and for managing the biasing effects of conflicts of interest.

Background: An orthopaedic malpractice claim alleges that the patient sustained a preventable iatrogenic injury. The analysis of a representative series of malpractice claims provides a unique view of alleged orthopaedic adverse events, revealing what can potentially go wrong across a spectrum of practice settings and anatomic locations. The goal of this study was to identify high-impact targets in order to institute measures to reduce claims through efforts focused on patient safety., Methods: The authors investigated 464 consecutive closed malpractice claims from the nation's largest insurer of medical liability. We analyzed the claims by anatomical site, type of care rendered, type of allegation, and payment. We calculated an "impact factor" for each claim type by dividing the percentage of total payments for each type by the percentage of total claims for that type., Results: Our analysis revealed major concerns regarding patient safety within this series of malpractice claims. One-third of the claims alleged permanent disabling injuries, including amputations, brain damage, and major nerve damage. The highest impact allegations were failure to protect structures in the surgical field (41% of total payments to plaintiffs, 15% of all claims, impact factor of 2.7) and failure to prevent, diagnose, and/or treat complications of treatment (16% of total payments, 7% of all claims, impact factor of 2.3). Spine procedures had high impact (1.9), representing 28% of dollars paid and 15% of claims, with 45% of spine claims involving death or severe permanent injury. Failure of implant positioning was commonly alleged in hip and knee arthroplasty. In claims related to fracture care, the most common allegations were related to malunions, nonunions, dislocations, failure to protect structures in the surgical field, infection, and treatment complications. Total payment for the eighty-eight claims paid was $17,917,614 (U.S. dollars adjusted to 2009)., Conclusions: Regarding clinical relevance, this analysis suggests risk areas for targeted efforts to improve patient safety and reduce malpractice claims.

Background: Propionibacterium acnes has been grown on culture in half of the reported cases of chronic infection associated with shoulder arthroplasty. The presence of this organism can be overlooked because its subtle presentation may not suggest the need for culture or because, in contrast to many orthopaedic infections, multiple tissue samples and weeks of culture incubation are often necessary to recover this organism. Surgical decisions regarding implant revision and antibiotic therapy must be made before the results of intraoperative cultures are known. In the present study, we sought clinically relevant prognostic evidence that could help to guide treatment decisions., Methods: We statistically correlated preoperative and intraoperative observations on 193 shoulder arthroplasty revisions that were performed because of pain, loosening, or stiffness with the results of a Propionibacterium acnes-specific culture protocol. Regression models were used to identify factors predictive of a positive culture for Propionibacterium acnes., Results: One hundred and eight of the 193 revision arthroplasties were associated with positive cultures; 70% of the positive cultures demonstrated growth of Propionibacterium acnes. The rate of positive cultures per shoulder increased with the number of culture specimens obtained from each shoulder. Fifty-five percent of the positive cultures required observation for more than one week. Male sex, humeral osteolysis, and cloudy fluid were each associated with significant increases of ≥ 600% in the likelihood of obtaining a positive Propionibacterium acnes culture. Humeral loosening, glenoid wear, and membrane formation were associated with significant increases of >300% in the likelihood of obtaining a positive Propionibacterium acnes culture., Conclusions: Preoperative and intraoperative factors can be used to help to predict the risk of a positive culture for Propionibacterium acnes. This evidence is clinically relevant to decisions regarding prosthesis removal or retention and the need for immediate antibiotic therapy at the time of revision shoulder arthroplasty before the culture results become available., Level of Evidence: Prognostic Level II. See Instructions for Authors for a complete description of levels of evidence.

Background: Knowledge of the factors affecting the prognosis for improvement in function and comfort with time after shoulder arthroplasty is important to clinical decision-making. This study sought to identify some of these factors in 176 consecutive patients undergoing the ream-and-run procedure., Methods: The time course for improvement in patient function and comfort was determined for the entire group as well as for subsets by sex, age, diagnosis, preoperative function, and surgery date. Patients having repeat surgery were analyzed in detail., Results: Shoulder comfort and function increased progressively after the ream-and-run procedure, reaching a steady state by approximately twenty months. The shoulders in 124 patients with at least two years of follow-up were improved by a minimal clinically important difference. The shoulders in sixteen patients with at least two years of follow-up were not improved by the minimal clinically important difference. Twenty-two patients had repeat procedures, but only seven had revision to a total shoulder arthroplasty. Fourteen patients did not have either a known revision arthroplasty or two years of follow-up. The best prognosis was for male patients over the age of sixty years, with primary osteoarthritis, no prior surgical procedures, a preoperative score on the simple shoulder test of ≥5 points, and surgery after 2004. Repeat surgical procedures were more common in patients who had a greater number of surgical procedures before the ream-and-run surgery., Conclusions: This study is unique in that it characterizes the factors affecting the time course for improvement in shoulder comfort and function after a ream-and-run procedure. Improvement occurs after this procedure for at least 1.5 years. This procedure appears to be best suited for an older male patient with reasonable preoperative shoulder function without prior shoulder surgery., Level of Evidence: Prognostic Level II. See Instructions for authors for a complete description of levels of evidence.

Background: Acromioplasty for impingement syndrome of the shoulder is one of the most common orthopaedic surgical procedures. The rate with which this procedure is performed has increased dramatically. This investigation sought high levels of evidence in the published literature related to five hypotheses pertinent to the concept of the impingement syndrome and the rationale supporting acromioplasty in its treatment., Methods: We conducted a systematic review of articles relevant to the following hypotheses: (1) clinical signs and tests can reliably differentiate the so-called impingement syndrome from other conditions, (2) clinically common forms of rotator cuff abnormality are caused by contact with the coracoacromial arch, (3) contact between the coracoacromial arch and the rotator cuff does not occur in normal shoulders, (4) spurs seen on the anterior aspect of the acromion extend beyond the coracoacromial ligament and encroach on the underlying rotator cuff, and (5) successful treatment of the impingement syndrome requires surgical alteration of the acromion and/or coracoacromial arch. Three of the authors independently reviewed each article and determined the type of study, the level of evidence, and whether it supported the concept of the impingement syndrome. Articles with level-III or IV evidence were excluded from the final analysis., Results: These hypotheses were not supported by high levels of evidence., Conclusions: The concept of impingement syndrome was originally introduced to cover the full range of rotator cuff disorders, as it was recognized that rotator cuff tendinosis, partial tears, and complete tears could not be reliably differentiated by clinical signs alone. The current availability of sonography, magnetic resonance imaging, and arthroscopy now enable these conditions to be accurately differentiated. Nonoperative and operative treatments are currently being used for the different rotator cuff abnormalities. Future clinical investigations can now focus on the indications for and the outcome of treatments for the specific rotator cuff diagnoses. It may be time to replace the nonspecific diagnosis of so-called impingement syndrome by using modern methods to differentiate tendinosis, partial tears, and complete tears of the rotator cuff.

Background: Glenohumeral chondrolysis is a complication of arthroscopic shoulder surgery characterized by the dissolution of the articular cartilage of the glenoid and the humeral head. An analysis of 375 intra-articular shoulder arthroscopic surgical procedures by an individual community orthopaedic surgeon was performed to explore which factors or combinations of factors might be associated with glenohumeral chondrolysis., Methods: The occurrence of chondrolysis was correlated with several demographic and surgical variables with use of hazard ratios from Cox proportional hazards models and Kaplan-Meier survivorship curves. Sensitivity analysis was used to examine the effect of two different definitions of the date of the onset of chondrolysis., Results: In this cohort, each case of documented chondrolysis was associated with the intra-articular post-arthroscopic infusion of a local anesthetic, either Marcaine (bupivacaine) or lidocaine. In an analysis of the group that received an intra-articular postoperative infusion of a local anesthetic, the risk of chondrolysis was found to be greater for those with one or more suture anchors placed in the glenoid, for younger patients, and for those who had the surgery near the end of the ten-year study period., Conclusions: To our knowledge, this is the first Level-II retrospective cohort study of the factors associated with the development of post-arthroscopic glenohumeral chondrolysis. In this cohort of intra-articular shoulder arthroscopic procedures, chondrolysis was observed only in cases in which either Marcaine or lidocaine had been infused into the joint during the postoperative period. Avoiding such a postoperative infusion may reduce the risk of chondrolysis., (© 2011 by the Journal of Bone and Joint Surgery, Incorporated)

Background: Glenoid component loosening is a common cause of failure of total shoulder arthroplasty. It has been proposed that the heat generated during glenoid preparation may reach temperatures capable of producing osteonecrosis at the bone-implant interface. We hypothesized that temperatures sufficient to induce thermal necrosis can be produced with routine drilling and reaming during glenoid preparation for shoulder arthroplasty in vivo. Furthermore, we hypothesized that irrigation of the glenoid during reaming can reduce this temperature increase., Methods: Real-time, high-definition, infrared thermal video imaging was used to determine the temperatures produced by drilling and reaming during glenoid preparation in ten consecutive patients undergoing total shoulder arthroplasty. The maximum temperature and the duration of temperatures greater than the established thresholds for thermal necrosis were documented. The first five arthroplasties were performed without irrigation and were compared with the second five arthroplasties, in which continuous bulb irrigation was used during drilling and reaming. A one-dimensional finite element model was developed to estimate the depth of penetration of critical temperatures into the bone of the glenoid on the basis of recorded surface temperatures., Results: Our first hypothesis was supported by the recording of maximum surface temperatures above the 56°C threshold during reaming in four of the five arthroplasties done without irrigation and during drilling in two of the five arthroplasties without irrigation. The estimated depth of penetration of the critical temperature (56°C) to produce instantaneous osteonecrosis was beyond 1 mm (range, 1.97 to 5.12 mm) in four of these patients during reaming and one of these patients during drilling, and two had estimated temperatures above 56°C at 3 mm. Our second hypothesis was supported by the observation that, in the group receiving irrigation, the temperature exceeded the critical threshold in only one specimen during reaming and in two during drilling. The estimated depth of penetration for the critical temperature (56°C) did not reach a depth of 1 mm in any of these patients (range, 0.07 to 0.19 mm)., Conclusions: Temperatures sufficient to induce thermal necrosis of glenoid bone can be generated by glenoid preparation in shoulder arthroplasty in vivo. Frequent irrigation may be effective in preventing temperatures from reaching the threshold for bone necrosis during glenoid preparation.

Background: The reported outcomes of shoulder arthroplasty in patients under the age of fifty years are worse than those in patients over fifty. While there are several possible explanations for this finding, we explored the possibility that patients who had a primary shoulder arthroplasty when they were under fifty years of age differed from those who had the procedure when they were over fifty with respect to their pre-arthroplasty self-assessed comfort and function, sex distribution, and specific type of arthritis., Methods: The study group consisted of patients with glenohumeral arthritis who were treated with a primary shoulder arthroplasty by the same surgeon between 1990 and 2008. For each decade of age, the sex distribution, the pre-arthroplasty self-assessed shoulder comfort and function, and the prevalence of twelve different diagnoses were documented. We reviewed the series for three potential causes of worse outcomes in patients under fifty years of age as compared with those over fifty years of age: (1) a higher percentage of women, (2) a lower score for pre-arthroplasty self-assessed comfort and function, and (3) more complex pathological conditions., Results: Patients under the age of fifty years were not more likely than those over fifty to be female or to have a lower pre-arthroplasty self-assessed comfort and function score, but they did have more complex pathological conditions, such as capsulorrhaphy arthropathy, rheumatoid arthritis, and posttraumatic arthritis. Only 21% of the younger patients had primary degenerative joint disease, whereas 66% of the older patients had that diagnosis. This difference was significant (p < 0.000000001)., Conclusions: Surgeons performing shoulder arthroplasty in individuals under the age of fifty should be prepared to encounter pathological conditions such as capsulorrhaphy arthropathy, rheumatoid arthritis, and posttraumatic arthritis rather than primary osteoarthritis, which is more common in individuals older than fifty. The pathoanatomy in these younger patients may complicate the surgery, the rehabilitation, and the outcome of the shoulder arthroplasty.

Background: With the aging of the world's population, the social and economic implications of osteoporotic fractures are at epidemic proportions. This study was performed to test the hypothesis that a proximal humeral fracture is an independent risk factor for a subsequent hip fracture and that the risk of the subsequent hip fracture is highest within the first five years after the humeral fracture., Methods: A cohort of 8049 older white women with no history of a hip or humeral fracture who were enrolled in the Study of Osteoporotic Fractures was followed for a mean of 9.8 years. The risk of hip fracture after an incident humeral fracture was estimated with use of age-adjusted Cox proportional hazards regression analysis with time-varying variables; women without a humeral fracture were the reference group. Cox regression analysis was used to evaluate the timing between the proximal humeral and subsequent hip fracture. Risk factors were determined on the basis of a review of the current literature, and we chose the variables that were most predictive and easily ascertained in a clinical setting., Results: Three hundred and twenty-one women sustained a proximal humeral fracture, and forty-four of them sustained a subsequent hip fracture. After adjustment for age and bone mineral density, the hazard ratio for hip fracture for subjects with a proximal humeral fracture relative to those without a proximal humeral fracture was 1.83 (95% confidence interval = 1.32 to 2.53). After multivariate adjustment, this risk appeared attenuated but was still significant (hazard ratio = 1.57; 95% confidence interval = 1.12 to 2.19). The risk of a subsequent hip fracture after a proximal humeral fracture was highest within one year after the proximal humeral fracture, with a hazard ratio of 5.68 (95% confidence interval = 3.70 to 8.73). This association between humeral and hip fracture was not significant after the first year, with hazard ratios of 0.87 (95% confidence interval = 0.48 to 1.59) between one and five years after the humeral fracture and 0.58 (95% confidence interval = 0.22 to 1.56) after five years., Conclusions: In this cohort of older white women, a proximal humeral fracture independently increased the risk of a subsequent hip fracture more than five times in the first year after the humeral fracture but was not associated with a significant increase in the hip fracture risk in subsequent years.

Glenoid component failure is the most common complication of total shoulder arthroplasty. Glenoid components fail as a result of their inability to replicate essential properties of the normal glenoid articular surface to achieve durable fixation to the underlying bone, to withstand repeated eccentric loads and glenohumeral translation, and to resist wear and deformation. The possibility of glenoid component failure should be considered whenever a total shoulder arthroplasty has an unsatisfactory result. High-quality radiographs made in the plane of the scapula and in the axillary projection are usually sufficient to evaluate the status of the glenoid component. Failures of prosthetic glenoid arthroplasty can be understood in terms of failure of the component itself, failure of seating, failure of fixation, failure of the glenoid bone, and failure to effectively manage eccentric loading. An understanding of these modes of failure leads to strategies to minimize complications related to prosthetic glenoid arthroplasty.

Background: Active and young individuals with glenohumeral arthritis who are treated with total glenohumeral arthroplasty are at risk for loosening or wear of the prosthetic glenoid component. This study tests the hypothesis that patients with severe glenohumeral arthritis have improvement in self-assessed shoulder comfort and function at two to four years after treatment with the combination of humeral hemiarthroplasty and concentric glenoid reaming without tissue or prosthetic component interposition., Methods: Thirty-seven consecutive patients (thirty-eight shoulders), with a mean age of fifty-seven years, who were managed by one surgeon were enrolled in this prospective study. The procedure consisted of an uncemented humeral hemiarthroplasty combined with reaming of the glenoid to a diameter 2 mm larger than that of the prosthetic humeral head. The duration of follow-up ranged from two to four years (average, 2.7 years) for thirty-five shoulders. Self-assessed comfort and function was documented with use of the Simple Shoulder Test, and radiographs were evaluated., Results: Thirty-two shoulders demonstrated improved comfort and function according to patient self-assessment, one demonstrated no change, and two had worse function following the procedure. The total number of Simple Shoulder Test functions that could be performed increased from 4.7 (of a possible 12.0) before surgery to 9.4 at the time of the final follow-up. The patients demonstrated significant improvement in ten of the twelve individual functions of the Simple Shoulder Test (p < 0.022 to p < 0.00001). With the numbers studied, gender, diagnosis, age, glenoid wear, and preoperative glenoid erosion did not significantly affect final shoulder function or overall improvement. The range of motion was significantly improved for all individuals (p < 0.00001). Radiographically, twenty-two patients had a joint space between the glenoid bone and the humeral prosthesis at the time of final follow-up. These shoulders had significantly better function than those without a preserved joint space (p < 0.017). There were no surgical complications and no revisions to total shoulder arthroplasty., Conclusions: At a minimum follow-up of two years, a selected series of patients who had humeral hemiarthroplasty with concentric glenoid reaming for the treatment of glenohumeral arthritis showed significant improvement in self-assessed shoulder comfort and function. Further study, however, is needed before routine application of this procedure can be recommended., Level of Evidence: Therapeutic Level IV.

Background: Both arthroscopic and open surgical repairs are utilized for the management of anterior glenohumeral instability. To determine the evidence supporting the relative effectiveness of these two approaches, we conducted a rigorous and comprehensive analysis of all reports comparing arthroscopic and open repairs., Methods: A systematic analysis of eighteen published or presented studies was performed to determine if there were significant differences between the two approaches with regard to recurrence (recurrent dislocation, subluxation, and/or apprehension and/or a reoperation for instability), return to work and/or sports, and Rowe scores. We also performed subgroup analysis to determine if the quality of the study or the arthroscopic technique influenced the results., Results: We identified four randomized controlled trials, ten controlled clinical trials, and four other comparative studies. Results were influenced both by the quality of the study and by the arthroscopic technique. Meta-analysis revealed that, compared with open methods, arthroscopic repairs were associated with significantly higher risks of recurrent instability (p < 0.00001, relative risk = 2.37, 95% confidence interval = 1.66 to 3.38), recurrent dislocation (p < 0.0001, relative risk = 2.74, 95% confidence interval = 1.75 to 4.28), and a reoperation (p = 0.002, relative risk = 2.32, 95% confidence interval = 1.35 to 3.99). When considered alone, arthroscopic suture anchor techniques were associated with significantly higher risks of recurrent instability (p = 0.01, relative risk = 2.25, 95% confidence interval = 1.21 to 4.17) and recurrent dislocation (p = 0.004, relative risk = 2.57, 95% confidence interval = 1.35 to 4.92) than were open methods. Arthroscopic approaches were also less effective than open methods with regard to enabling patients to return to work and/or sports (p = 0.03, relative risk = 0.87, 95% confidence interval = 0.77 to 0.99). On the other hand, analysis of the randomized clinical trials indicated that arthroscopic repairs were associated with higher Rowe scores (p = 0.002, standardized mean difference = 0.43, 95% confidence interval = 0.16 to 0.70) than were open methods. Similarly, analysis of the arthroscopic suture anchor techniques alone showed the Rowe scores to be higher (p = 0.04, standardized mean difference = 0.29, 95% confidence interval = 0.01 to 0.56) than those associated with open methods., Conclusions: The available evidence indicates that arthroscopic approaches are not as effective as open approaches in preventing recurrent instability or enabling patients to return to work. Arthroscopic approaches resulted in better function as reflected by the Rowe scores in the randomized clinical trials. The study design and the arthroscopic technique had substantial effects on the results of the analysis.

Background: Glenohumeral instability associated with a large osseous defect of the glenoid can be treated with bone graft to restore the glenoid concavity. The shape and positioning of the graft is critical: a graft that encroaches on the extrapolated glenoid curvature can prevent the head from seating completely in the glenoid, whereas a graft that is too far from the curvature does not restore the glenoid concavity. The purpose of the present study was to investigate how the intrinsic stability that is provided by the glenoid is affected by (1) a standardized anteroinferior glenoid defect and (2) different configurations of anteroinferior glenoid bone graft., Methods: The anteroinferior stability provided by the glenoid was quantitated by measuring the balance stability angle in that direction. The balance stability angle is the maximal angle that the direction of the net humeral joint-reaction force can make with the glenoid centerline before dislocation takes place. The anteroinferior stability was assessed in each of four fresh-frozen, grossly normal cadaveric glenoids in (1) the unaltered state, (2) after the creation of a standardized defect of a magnitude that has been reported by other investigators to be sufficient to require a bone graft, and (3) after each step of a series of bone-grafting procedures involving grafts of varying height and contour., Results: The anteroinferior glenoid defect significantly diminished the anteroinferior stability by almost 50% (p = 0.006). Bone-grafting significantly increased the stability provided by the glenoid. The increase in stability as compared with that of the glenoid with the standardized defect was particularly marked for contoured graft heights of 6 and 8 mm, for which the increases were 150% (p = 0.0001) and 229% (p < 0.00025), respectively. Contouring of the graft minimized the potential for unwanted contact between the ball and the graft., Conclusions: Anteroinferior shoulder instability caused by an osseous defect in the glenoid can be corrected with bone-grafting. The effectiveness of the graft in restoring the lost stability is related both to its height and to the extent to which it is contoured as long as the graft is not so prominent that it forces the ball posteriorly from the center of the glenoid.

Background: In most clinical reports on rotator cuff repair, acromioplasty was done as part of the procedure. In this prospective study, we evaluated the hypothesis that rotator cuff repair without acromioplasty would result in a substantial improvement in shoulder comfort and function., Methods: Ninety-six consecutive primary repairs of full-thickness tears of the rotator cuff were performed through a deltoid-muscle-splitting incision that preserved the integrity of the coracoacromial arch and the deltoid insertion. All patients were invited to participate in a prospective study involving periodic self-assessment of shoulder function with the Simple Shoulder Test and general health status with the Short Form-36 (SF-36) questionnaire, both of which are validated instruments. Sixty-one patients provided follow-up information for at least two years postoperatively, and the average duration of follow-up was five years. Thirty-four of the tears involved the supraspinatus tendon alone; sixteen involved the supraspinatus and infraspinatus tendons; and eleven involved the supraspinatus, infraspinatus, and subscapularis tendons., Results: The percentage of shoulders that could be used to perform each of the twelve functions on the Simple Shoulder Test was significantly increased postoperatively (p < 0.002). Men and women had different degrees of function preoperatively (p < 0.00000001) and postoperatively (p < 0.001), but the improvement in function was essentially identical for the two genders. The mean improvement in the number of shoulder tests that could be performed was best for the patients with one-tendon tears (4.9 tests), next best for those with two-tendon tears (3.6 tests), and worst for those with three-tendon tears (3.3 tests). SF-36 scores for physical role (p < 0.003) and comfort (p < 0.0001) were significantly improved postoperatively., Conclusions: Significant improvement in self-assessed shoulder comfort and in each of the twelve shoulder functions was observed after rotator cuff repairs performed without acromioplasty. The technique that we used is very similar to that described by Codman almost seventy years ago.

Background: In a shoulder requiring arthroplasty, if the glenoid is flat or biconcave, the surgeon can restore the desired glenoid stability by using a glenoid prosthesis with a known surface geometry or by modifying the surface of the glenoid to a geometry that provides the desired glenoid stability. This study tested the hypotheses that (1) the stability provided by the glenoid is reduced by the removal of the articular cartilage; (2) the stability contributed by the glenoid is compromised by loss of its articular cartilage, and this lost stability can be restored by spherical reaming along the glenoid centerline; and (3) the stability of a reamed glenoid is comparable with that of a native glenoid and with that of a polyethylene glenoid with similar surface geometry; and (4) the glenoid stability can be predicted from the glenoid surface geometry., Methods: The stability provided by the glenoid in a given direction can be characterized by the maximal angle that the humeral joint reaction force can make with the glenoid centerline before the humeral head dislocates; this quantity is defined as the balance stability angle in the specified direction. The balance stability angles were both calculated and measured in eight different directions for an unused polyethylene glenoid component and eleven cadaveric glenoids in four different states: (1) native without the capsule or the rotator cuff, (2) denuded of cartilage and labrum, (3) after reaming the glenoid surface around the glenoid centerline with use of a spherical reamer with a radius of 25 mm, and (4) after reaming around the glenoid centerline with use of a spherical reamer with a radius of 22.5 mm., Results: The calculated and measured balance stability angles for each direction in each glenoid were strongly correlated. Denuding the glenoids of the articular cartilage reduced the glenoid contribution to stability, especially in the posterior direction. Reaming the glenoid restored the stability to values comparable with those of the normal glenoid. For example, the average calculated balance stability angle (and standard deviation) in the posterior direction for all eleven glenoids was 24 degrees for the native glenoids, 14 degrees for the denuded glenoids, 25 degrees for the glenoids reamed to a radius of 25 mm, and 33 degrees for the glenoids reamed to a radius of 22.5 mm. The values for the glenoids reamed to 25 mm (25 degrees ) were similar to those of a polyethylene glenoid of the same radius of curvature. For glenoids reamed to 22.5 mm, the average difference between the actual balance stability angle and that predicted from the glenoid geometry was 3.4 degrees +/- 2.4 degrees., Conclusions: The glenoid contribution to shoulder stability was decreased by the removal of cartilage and labrum and was restored by spherical reaming to a level similar to resurfacing the glenoid with a polyethylene component.

Background: The relationship between the characteristics of the shoulder that can be determined before humeral hemiarthroplasty and the functional improvement after surgery is not known. The goal of this study was to test the hypothesis that the functional outcome of this procedure correlated significantly with factors that are identifiable preoperatively., Methods: The study group included seventy-one shoulders in sixty-eight patients undergoing hemiarthroplasty, performed by the same surgeon, for diagnoses other than acute fracture. The mean age of the patients was sixty-one years (range, thirty to eighty-three years). The results were characterized in terms of the change in self-assessed shoulder function and general health status at an average of forty-nine months (range, twenty-four to 142 months) after surgery., Results: The preoperative absence of erosion of the glenoid was associated with greater improvement in shoulder function and level of comfort after hemiarthroplasty (p < 0.001). Shoulders that had not had previous surgery had greater functional improvement than did those that had previous surgery (p = 0.012). Shoulders with an intact rotator cuff showed significantly (p < 0.5) greater improvement in the ability to lift weight above shoulder level after hemiarthroplasty (p <0.5). With regard to diagnoses, shoulders with rheumatoid arthritis, capsulorrhaphy arthropathy, and cuff tear arthropathy had the least functional improvement, whereas those with osteonecrosis (p = 0.0004) and with primary (p = 0.02) and secondary degenerative joint disease (p = 0.03) had the greatest improvement. Patient age and gender did not significantly affect the outcome., Conclusions: These results suggest that the functional improvement following humeral hemiarthroplasty is related to factors that are identifiable before surgery. These data may be of benefit in preoperative discussions with patients who have a shoulder disorder and are considering treatment with hemiarthroplasty.

Background: Rotator cuff tears are among the most common conditions of the shoulder. One of the major difficulties in studying patients with rotator cuff tears is that the clinical expression of these tears varies widely and different practices may have substantially different patient populations. The goals of the present prospective multipractice study were to use patient self-assessment questionnaires (1) to identify some of the characteristics of patients with rotator cuff tears, other than the size of the cuff tear, that are correlated with shoulder function, and (2) to determine whether there are significant differences in these characteristics among patients from the practices of different surgeons., Methods: Ten surgeons enrolled a total of 333 patients with a full-thickness tear of the supraspinatus tendon into this prospective study. Each patient completed self-assessment questionnaires that included items regarding demographic characteristics, prior treatment, medical and social comorbidities, general health status, and shoulder function., Results: As expected, patients who had an infraspinatus tendon tear as well as a supraspinatus tendon tear had significantly worse ability to use the arm overhead compared with those who had a supraspinatus tear alone (p < 0.005). However, shoulder function and health status were correlated with patient characteristics other than the size of the rotator cuff tear. The number of shoulder functions that were performable was correlated with the subscales of the Short Form-36 and was inversely associated with medical and social comorbidities. The patients from the ten different surgeon practices showed significant differences in almost every parameter, including age, gender, method of tear documentation, tear size, prior treatment, medical and social comorbidities, general health status, and shoulder function., Conclusions: Clinical studies on the natural history of rotator cuff tears and the effectiveness of treatment must control for a wide range of variables, many of which do not pertain directly to the shoulder. Patients from the practices of different surgeons cannot be assumed to be similar with respect to these variables. Patient self-assessment questionnaires appear to offer a practical method of uniform assessment across different practices.

Background: The technique of shoulder arthroplasty requires a method for securely and durably fixing the humeral component in the medullary canal of the proximal part of the humerus. As an alternative to fixation by cementing or tissue ingrowth, we explored the effectiveness of using a prosthesis with a metaphyseal taper from the anatomic neck to the diaphysis. This component is designed to obtain press-fit fixation in the cancellous bone of the metaphysis rather than in the cortical bone of the diaphysis. We tested the hypothesis that this press-fit humeral stem, designed to respect the taper of the proximal part of the humeral canal, would be associated with a low rate of loosening in patients managed with primary shoulder arthroplasty for osteoarthritis., Methods: A prospective study was conducted to evaluate the prevalence of radiolucent lines around press-fit humeral prostheses. One hundred and thirty-one patients with glenohumeral osteoarthritis were followed for a minimum of two years. A zonal method of evaluating radiolucent lines was established. Shift in position and subsidence were judged qualitatively., Results: No component showed subsidence or a shift in position. Fifty shoulders (39%) had no radiolucency. Two shoulders had radiolucency around the proximal part of the prosthesis, and seventy-five had radiolucency at the distal tip. Eleven radiolucencies were > or =1 mm in width. A neutral stem orientation was significantly less likely to be associated with radiolucency (p = 0.026). The prevalence of radiolucent lines did not differ between patients managed with hemiarthroplasty and those managed with total shoulder arthroplasty, and it did not increase with longer periods of follow-up., Conclusions: In patients managed with shoulder arthroplasty, the fixation of a press-fit humeral component that has a tapered metaphyseal segment is comparable with that reported for cemented components and superior to that reported for press-fit cylindrical components., Clinical Relevance: This type of fixation may provide an alternative to cementing of the humeral stem in individuals with glenohumeral osteoarthritis.

Background: Both shoulder surgeons and patients who are considering total shoulder arthroplasty are interested in the anticipated improvement in shoulder comfort and function after the procedure. The purpose of the present study was to characterize shoulder-specific functional gains in relation to preoperative shoulder function and to present this information in a way that can be easily communicated to patients who are considering this surgery., Methods: We analyzed the preoperative and follow-up shoulder function in patients managed with total shoulder arthroplasty for the treatment of primary glenohumeral osteoarthritis. Functional self-assessments were available for 102 (80%) of 128 shoulders after thirty to sixty months of follow-up. Outcome was assessed with respect to the change in the number of shoulder functions that were performable, the change in shoulder function as a percentage of the preoperative functional deficit, and the change in the ability to perform specific shoulder functions., Results: The average number of shoulder functions that were performable improved from four of twelve preoperatively to nine of twelve postoperatively (p < 0.01). Function improved in ninety-six shoulders (94%). The number of functions that were performable at the time of follow-up was positively associated with preoperative shoulder function (p < 0.05): the better the preoperative function, the better the follow-up function. The improvement in function was greatest for shoulders with less preoperative function (p < 0.01). On the average, patients regained approximately two-thirds of the functions that had been absent preoperatively. Significant improvement was noted in eleven of the twelve shoulder functions that were examined (p < 0.01). The chance of regaining a function that had been absent before surgery was 73%, whereas the chance of losing a function that had been present before surgery was 6%. Older men tended to have greater functional improvement than younger men., Conclusion: Total shoulder arthroplasty for the treatment of primary glenohumeral osteoarthritis significantly improves shoulder function. Postoperative function is related to preoperative function. The improvement that was observed in this clinical series can be conveyed to patients most simply by stating that, after surgery, shoulders typically regained approximately two-thirds of the functions that had been absent preoperatively.

Background: Radiolucent lines about the glenoid component of a total shoulder replacement are a common finding, even on initial postoperative radiographs. The achievement of complete osseous support of the component has been shown to decrease micromotion. We evaluated the ability of a group of experienced shoulder surgeons to achieve complete cementing and support in a series of patients managed with keeled and pegged glenoid components., Methods: We reviewed the initial postoperative radiographs of 493 patients with primary osteoarthritis who had been managed with total shoulder arthroplasty by seventeen different surgeons. One hundred and sixty-five patients were excluded because of inadequate radiographs, leaving 328 patients available for review. Of these, thirty-nine patients had a keeled component and 289 had a pegged component. The method of Franklin was used to grade the degree of radiolucency around the keeled components, and a modification of that method was used to grade the degree of radiolucency around the pegged components. The efficacy of component seating on host subchondral bone was evaluated with a newly constructed five-grade scale based on the percentage of the component that was supported by subchondral bone. Each radiograph was graded four times, by two separate reviewers on two separate occasions., Results: Radiolucencies were extremely common, with only twenty of the 328 glenoids demonstrating no radiolucencies. On a numeric scale (with 0 indicating no radiolucency and 5 indicating gross loosening), the mean radiolucency score was 1.8 +/- 0.9 for keeled components and 1.3 +/- 0.9 for pegged components (p = 0.0004). After defining categories of "better" and "worse" cementing, we found that pegged components more commonly had "better cementing" than did keeled components (p = 0.0028). Incomplete seating was also common, particularly among patients with keeled components. Ninety-five of the 121 pegged components that had been inserted by the most experienced surgeon had "better cementing," compared with eighty-five of the 168 pegged components that had been inserted by the remaining surgeons (p < 0.00001)., Conclusions: Perfectly cementing and seating a glenoid replacement is a difficult task. Radiolucencies and incomplete component seating occur more frequently in association with keeled components compared with pegged components. Surgeon experience may be an important variable in the achievement of a good technical outcome.