Patients with poor early clinical outcomes after anatomic total shoulder arthroplasty have sustained poor performance at 2 years from surgery.

PURPOSE: We sought to define the risk of persistent shoulder dysfunction after anatomic total shoulder arthroplasty (aTSA) beyond the early postoperative period and identify risk factors for persistent poor performance. METHODS: We retrospectively identified 144 primary aTSAs performed for primary osteoarthritis with early poor performance and 2-year minimum follow-up. Early poor performance was defined as a postoperative ASES score below the 20th percentile at 3- or 6-months (62 and 72 points, respectively). Persistent poor performance at 2 years was defined as failing to achieve the patient acceptable symptomatic state (PASS) [ASES = 81.7 points]. RESULTS: At 2-year follow-up, 51% (n = 74) of patients with early poor performance at either 3- or 6-month follow-up had persistent poor performance. There was no difference in the rate of persistent poor performance if patients were poor performers at the 3-, 6-month follow-up, or both (50% vs. 49% vs. 56%, P = .795). Of aTSAs achieving the PASS at 2-year follow-up, a greater proportion exceeded the minimal clinically important differences (MCID) [Forward elevation, external rotation, and all outcome scores] and substantial clinical benefit (SCB) [external rotation and all outcome scores] compared to persistent poor performers. However, over half of persistent poor performers still exceeded the MCID for all outcome measures (56-85%). Independent predictors of persistent poor performance were hypertension (2.61 [1.01-6.72], P = .044) and diabetes (5.14 [1.00-26.4], P = .039). CONCLUSION: Over half of aTSAs with an ASES score < 20th percentile at early follow-up had continued poor shoulder function at 2-years postoperatively. Persistent poor performance was best projected by preoperative hypertension and diabetes. LEVEL OF EVIDENCE: Level III; Retrospective Cohort Comparison using Large Database; Treatment Study.

Quantifying success after reverse total shoulder arthroplasty: the substantial clinically important percentage of maximal possible improvement.

BACKGROUND: Changes in preoperative to postoperative outcome scores are often used to quantify success after reverse total shoulder arthroplasty (rTSA). However, ceiling effects associated with many outcome scores limit the ability to differentiate success among high-functioning patients. The percentage of maximal possible improvement (%MPI) was introduced to simplify and better stratify patient success. The primary purpose of this study was to define the %MPI thresholds associated with substantial clinical improvement following primary rTSA and compare the rates of success as defined by those achieving the substantial clinical benefit (SCB) compared to the 30% MPI for different outcome scores. METHODS: A retrospective review was performed of an international shoulder arthroplasty database between 2003 and 2020. All primary rTSAs performed using a single implant system with a minimum 2-year follow-up were reviewed. Preoperative and postoperative outcome scores were evaluated for all patients to calculate improvement. Six outcome scores were assessed: the Simple Shoulder Test (SST), Constant, American Shoulder and Elbow Surgeons (ASES), University of California Los Angeles (UCLA), Shoulder Pain and Disability Index (SPADI), and Shoulder Arthroplasty Smart (SAS) scores. The proportion of patients achieving the SCB and 30% MPI was determined for each outcome score. Thresholds for the substantial clinically important %MPI (SCI-%MPI) were calculated using an anchor-based method for each outcome score and stratified by age and sex. RESULTS: Of total, 2573 shoulders with a mean follow-up of 47 months were included. Outcome scores with known ceiling effects (SST, ASES, UCLA, SPADI) had higher rates of patients achieving the 30% MPI compared to scores without ceiling effects (Constant, SAS). However, scores without ceiling effects had higher rates of patients achieving the SCB. The SCI-%MPI differed among outcome scores, and mean values were 47% for the SST, 35% for the Constant score, 50% for the ASES score, 52% for the UCLA score, 47% for the SPADI score, and 45% for the SAS score. The SCI-%MPI increased in patients older than 60 years (P < .001) except for the SAS and Constant scores. SCI-%MPI was greater in females for all scores assessed except the Constant and SPADI scores (P < .001 for all). The higher SCI-%MPI thresholds in these populations mean that these patients required a greater fraction of the MPI to have substantial improvement. CONCLUSION: The %MPI judged relative to patient-reported substantial clinical improvement offers an alternative method to quickly assess improvements across patient outcome scores. Given considerable variation in the %MPI corresponding to substantial clinical improvement, we recommend utilizing score-specific estimates of the SCI-%MPI to gauge success when evaluating patients undergoing primary rTSA.

Quantifying success after reverse total shoulder arthroplasty: the minimal clinically important percentage of maximal possible improvement.

BACKGROUND: In high functioning patients, the ceiling effect associated with many patient-reported outcome measures (PROMs) limits the ability to appropriately stratify success. The percentage maximal possible improvement (%MPI) was introduced as another evaluation tool, with a proposed threshold of success at 30%. It remains unclear if this threshold correlates with perceived patient success following shoulder arthroplasty. The purpose of this study was to compare the proportion of patients that achieved the minimal clinically important difference (MCID) and %MPI for different outcome scores and to define the %MPI thresholds associated with patient satisfaction following primary reverse total shoulder arthroplasty (rTSA). METHODS: A retrospective review was performed of an international shoulder arthroplasty database between 2003 and 2020. All primary rTSAs performed using a single implant system with minimum 2-year follow-up were reviewed. Pre- and postoperative outcome scores were evaluated for all patients to determine the raw improvement and %MPI. The proportion of patients achieving the MCID and 30% MPI were determined for each outcome score. Thresholds for the minimal clinically important %MPI (MCI-%MPI) were calculated using an anchor-based method for each outcome score and stratified by age and sex. RESULTS: A total of 2573 shoulders with a mean follow-up of 47 months were included. Outcome scores with known ceiling effects (Simple Shoulder Test [SST], Shoulder Pain and Disability Index [SPADI], University of California-Los Angeles shoulder score [UCLA]) had higher rates of patients achieving the 30% MPI but not the previously reported MCID. Inversely, outcome scores without significant ceiling effects (Constant and Shoulder Arthroplasty Smart [SAS] scores) had higher rates of patients achieving the MCID, but not the 30% MPI. The MCI-%MPI differed among outcome scores and mean values were as follows: 33% for the SST, 27% for the Constant score, 35% for the American Shoulder and Elbow Surgeons Standardized Shoulder Assessment Form (ASES) score, 43% for the UCLA score, 34% for the SPADI score, and 30% for the SAS score. The MCI-%MPI increased with greater age for SPADI (P < .04) and SAS (P < .01) scores, meaning that patients with higher thresholds required a greater fraction of the possible improvement for a given score to be satisfied but did not reach statistical significance for other scores. Females had a greater MCI-%MPI for the SAS and ASES scores and a lower MCI-MPI% for the SPADI score. CONCLUSION: The %MPI offers a simple method to quickly assess improvements across patient outcome scores. However, the %MPI that represents patient improvement after surgery is not uniformly the previously established 30% threshold. Surgeons should use score-specific estimates of the MCI-%MPI to gauge success when evaluating patients undergoing primary rTSA.

Quantifying success after anatomic total shoulder arthroplasty: the substantial clinically important percentage of maximal possible improvement.

BACKGROUND: Percentage maximal possible improvement (%MPI) has been described as a threshold by which to evaluate patient improvement after anatomic total shoulder arthroplasty (aTSA) that has favorable psychometric properties. The primary purpose of this study was to define the percentage maximal possible improvement (%MPI) thresholds associated with substantial clinical improvement following primary anatomic total shoulder arthroplasty (aTSA) and compare the rates of success as defined by those achieving the substantial clinical benefit (SCB) compared with the 30% MPI for different outcome scores. METHODS: A retrospective review was performed of an international shoulder arthroplasty database between 2003 and 2020. All primary aTSAs performed using a single implant system with minimum 2-year follow-up were reviewed. Pre- and postoperative outcome scores were evaluated for all patients to calculate improvement. Six outcome scores were assessed: the Simple Shoulder Test (SST), Constant, American Shoulder and Elbow Surgeons Standardized Shoulder Assessment Form (ASES), University of California-Los Angeles shoulder score (UCLA), Shoulder Pain and Disability Index (SPADI), and Shoulder Arthroplasty Smart (SAS) scores. The proportion of patients achieving the SCB and 30% MPI were determined for each outcome score. Thresholds for the substantial clinically important %MPI (SCI-%MPI) were calculated using an anchor-based method for each outcome score and stratified by age and sex. RESULTS: A total of 1593 shoulders with a mean follow-up of 59.3 months were included. Outcome scores with known ceiling effects (SST, ASES, UCLA) had higher rates of patients achieving the 30% MPI but not the previously reported SCB compared to scores without ceiling effects (Constant, SAS). The SCI-%MPI differed among outcome scores, and mean values were as follows: 48% for the SST, 39% for the Constant score, 53% for the ASES score, 55% for the UCLA score, 50% for the SPADI score, and 42% for the SAS score. The SCI-%MPI increased in patients older than 60 years (P ≤ .006 for all) and was greater in females for all scores assessed except the Constant score (P < .001 for all), meaning that patients with higher thresholds required a greater fraction of the maximum possible improvement for a given score to have substantial improvement. CONCLUSION: The %MPI judged relative to patient-reported substantial clinical improvement offers a new method to assess improvements across patient outcome scores. Given considerable variation in the %MPI corresponding to substantial clinical improvement, we recommend utilizing score-specific estimates of the SCI-%MPI to gauge success when evaluating patients undergoing primary aTSA.

Quantifying success after anatomic total shoulder arthroplasty: the minimal clinically important percentage of maximal possible improvement.

INTRODUCTION: Changes in pre- to postoperative outcome scores are often used to quantify success after anatomic total shoulder arthroplasty (aTSA). However, ceiling effects associated with many outcome scores limit the ability to differentiate success among high-functioning patients. The percentage maximal possible improvement (%MPI) was introduced to better stratify patient success; however, it is unclear if the 30% threshold first proposed correlates with perceived patient success across all outcome scores. The purpose of this study was to compare the proportion of patients that achieved the minimal clinically important difference (MCID) and %MPI for different outcome scores and to define the %MPI thresholds associated with patient satisfaction following primary aTSA. METHODS: A retrospective review was performed of an international shoulder arthroplasty database between 2003 and 2020. All primary aTSAs performed using a single implant system with minimum 2-year follow-up were reviewed. Pre- and postoperative outcome scores were evaluated for all patients to calculate improvement. The proportion of patients achieving the MCID and 30% MPI were determined for each outcome score. Thresholds for the minimal clinically important %MPI (MCI-%MPI) were calculated using an anchor-based method for each outcome score and stratified by age and sex. RESULTS: 1593 shoulders with a mean follow-up of 59.3 months were included. Outcome scores with known ceiling effects (Simple Shoulder Test [SST], American Shoulder and Elbow Surgeons Standardized Shoulder Assessment Form [ASES], University of California-Los Angeles shoulder score [UCLA]) had higher rates of patients achieving the 30% MPI but not the previously reported MCID. Inversely, outcome scores without significant ceiling effects (Constant and Shoulder Arthroplasty Smart [SAS] scores) had higher rates of patients achieving the MCID but not the 30% MPI. The MCI-%MPI differed among outcome scores, and mean values were as follows: 33% for the SST, 24% for the Constant score, 32% for the ASES score, 38% for the UCLA score, 30% for the Shoulder Pain and Disability Index score, and 33% for the SAS score. The MCI-%MPI increased with greater age (P < .003) and females had thresholds greater than or equal to males for all scores assessed, meaning that patients with higher thresholds required a greater fraction of the possible improvement for a given score to be satisfied. CONCLUSION: The %MPI offers a simple method to quickly assess improvements across patient outcome scores. However, the %MPI that represents patient improvement after surgery is not uniformly the previously established 30% threshold. Surgeons should use score-specific estimates of the MCI-%MPI to gauge success when evaluating patients undergoing primary aTSA.

Do patients with poor early clinical outcomes after reverse total shoulder arthroplasty ultimately improve?

BACKGROUND: Although most patients undergoing reverse total shoulder arthroplasty (rTSA) have substantial improvement in pain and function at early follow-up, improvements in pain and range of motion progress more slowly during postoperative rehabilitation in a subset of patients. The purpose of this study was to define a patient's risk of persistent shoulder dysfunction beyond the early postoperative period and identify risk factors for persistent poor performance. METHODS: We retrospectively reviewed 292 primary rTSAs with early poor performance and a preoperative diagnosis of osteoarthritis, cuff tear arthropathy, or rotator cuff tear from a multicenter database. Early poor performance was defined as a postoperative American Shoulder and Elbow Surgeons (ASES) score below the 20th percentile at 3 months (58 points) or 6 months (65 points) postoperatively. Persistent poor performance at 2 years was defined as failure to achieve the patient acceptable symptomatic state for rTSA (77.3 points for the ASES score). The primary outcome was the rate of persistent poor performance. Secondarily, we compared the clinical outcomes of persistent poor performers vs. shoulders that improved at 2-year follow-up and assessed risk factors for persistent poor performance. RESULTS: At 2-year follow-up, 61% of patients (n = 178) with poor performance at either 3- or 6-month follow-up had persistent poor performance. The rate increased to 85% if poor performance occurred at both 3- and 6-month follow-up. The minimal clinically important difference and substantial clinical benefit for range of motion and outcome scores were exceeded by early poor performers at rates of 83%-92% and 60%-77%, respectively, at 2-year follow-up. On multivariate logistic regression analysis, independent predictors of persistent poor performance after rTSA were lack of hypertension (odds ratio [OR], 0.27; 95% confidence interval [CI], 0.13-0.57; P < .001), heart disease (OR, 2.89; 95% CI, 1.24-6.77; P = .011), uncemented humeral fixation (OR, 0.11; 95% CI, 0.01-1.18; P = .037), previous shoulder surgery (OR, 2.14; 95% CI, 1.06-4.30; P = .031), lower preoperative ASES score (OR, 0.92; 95% CI, 0.87-0.97; P = .002), and lower preoperative subjective rating of pain at its worst (OR, 0.73; 95% CI, 0.54-0.99; P = .038). DISCUSSION: Despite the fact that 85% of rTSA patients with an ASES score below the 20th percentile at early follow-up exceeded the minimal clinically important difference for improvement in the ASES score at 2-year clinical follow-up, 61% still had persistent poor performance, with failure to achieve the patient acceptable symptomatic state for the ASES score. Persistent poor performance after rTSA was best predicted by a history of shoulder surgery and a poorer preoperative ASES score. These findings can aid surgeons when counseling patients both preoperatively and postoperatively. In the setting of early poor performance, the risk of persistent poor performance must be balanced against the potential outcomes of revision surgery when considering early surgical intervention.

Shoulder arthroplasty after prior anterior shoulder instability surgery: a matched cohort analysis.

PURPOSE: To evaluate the effect of prior anterior shoulder instability surgery (SIS) on the outcomes and complications of primary anatomic total shoulder arthroplasty (aTSA) and reverse total shoulder arthroplasty (rTSA). METHODS: Between 2007 and 2018, 38 primary total shoulder arthroplasties (TSA) (22 aTSA and 16 rTSA) with a prior SIS and a minimum of 2 years of follow-up were identified. This cohort was matched 1:3 based on age, sex, body mass index, year of surgery, and dominant shoulder. aTSA and rTSA were matched to patients with primary osteoarthritis (OA) and rotator cuff tear arthropathy (CTA), respectively. RESULTS: TSA produced similar postoperative pain, ROM, patient-reported outcome measures, complications, and revisions in those with prior SIS vs. controls. aTSA with prior SIS demonstrated worse final postoperative abduction (116° vs. 133°; P = 0.046) and abduction improvement (24° vs. 47°; P = 0.034) compared to OA controls. Both aTSA and rTSA with prior SIS demonstrated significant improvements from baseline across all metrics, with no significant differences between the groups. aTSA and rTSA with prior SIS demonstrated no differences to controls in complications (4.6% vs. 6.1%; P = .786 and 0% vs. 6.3%. P = .183) or revisions (4.6% vs. 4.6%; P = .999 and 0% vs. 4.2%; P = .279). CONCLUSIONS: TSA after prior SIS surgery can improve both pain and function without adversely increasing the rates of complications or revision surgery. When compared to patients without prior SIS, aTSA demonstrated worse abduction; however, all other functional differences remained statistically similar. LEVEL OF EVIDENCE: III; Retrospective Cohort Comparison; Treatment Study.

Reverse Shoulder Arthroplasty After Prior Rotator Cuff Repair: A Matched Cohort Analysis.

INTRODUCTION: Rotator cuff repair (RCR) is commonly performed before reverse shoulder arthroplasty (RSA) with conflicting evidence on the effect on arthroplasty outcomes. The purpose of this investigation was to evaluate the effect of a prior RCR on the outcomes and complications of primary RSA. METHODS: Between 2007 and 2017, 438 RSAs performed in patients with a prior RCR and 876 case-matched controls were identified from a multicenter database. Patients were grouped based on a preoperative diagnosis of glenohumeral osteoarthritis (GHOA) and rotator cuff tear arthropathy (CTA). Data collected included range of motion, strength, complications, and revisions. Additional clinical metrics included American Shoulder and Elbow Society score, Constant score, Shoulder Pain and Disability Index, Simple Shoulder Test, and the University of California Los Angeles shoulder score. RESULTS: Compared with controls, both GHOA and CTA study groups demonstrated lower postoperative forward elevation (FE) (133° versus 147°, P < 0.001; 133° versus 139°, P = 0.048) and FE trength (6.5 versus 8.2, P = 0.004; 6.1 versus 7.3, P = 0.014). In addition, inferior improvements were observed in the GHOA and CTA study groups with respect to abduction (38° versus 52°, P = 0.001; 36° versus 49°, P = 0.001), FE (41° versus 60°, P < 0.001; 38° versus 52°, P = 0.001), ER (16° versus 25°, P < 0.001; 10° versus 17°, P = 0.001), and Constant score (28.4 versus 37.1, P < 0.001; 26.2 versus 30.9, P = 0.016). Compared with controls, no differences were observed in the GHOA and CTA study groups with respect to notching (11.2% versus 5.6%, P = 0.115; 5.8% versus 7.9%, P = 0.967), complications (4.3% versus 1.6%, P = 0.073; 2.5% versus 2.7%, P = 0.878), and revision surgery (3.1% versus 0.9%, P = 0.089; 1.1% versus 1.3%, P = 0.822). CONCLUSION: RSA after a prior RCR improves both pain and function, without increasing scapular notching, complications, or revision surgery. However, compared with patients without a prior RCR, postoperative shoulder function may be slightly decreased. LEVEL OF EVIDENCE: III; Retrospective Cohort Study.

Reverse shoulder arthroplasty yields similar results to anatomic total shoulder arthroplasty for the treatment of humeral head avascular necrosis.

BACKGROUND: Avascular necrosis (AVN) of the humeral head frequently results in humeral head collapse and end-stage arthritic changes of the glenohumeral joint. Despite the recent proliferation of reverse total shoulder arthroplasty (RTSA), reports on the use of RTSA for AVN remain limited. The purpose of this study was to document the outcomes of shoulders indicated for RTSA in the setting of humeral head AVN and compare these with AVN shoulders indicated for the gold standard, anatomic total shoulder arthroplasty (aTSA). METHODS: A retrospective review of a multinational shoulder arthroplasty database was performed between August 2005 and August 2017. All shoulders with a preoperative diagnosis of AVN (aTSA in 52 and RTSA in 67) were reviewed. The shoulders in the RTSA cohort were matched (1:1) to shoulders with cuff tear arthropathy, whereas the shoulders in the aTSA cohort were matched (1:1) to shoulders with primary osteoarthritis. The mean follow-up period was 47 months (range, 24-130 months) for RTSA and 54 months (range, 24-124 months) for aTSA. Shoulders were evaluated for active range of motion (ROM) and patient-reported outcome measures (PROMs) prior to surgery and at latest follow-up. Patients treated with RTSA were compared with both the aTSA study cohort and the control group using the Student t test or χ2 test as indicated. RESULTS: RTSAs performed for AVN demonstrated significant improvements in all ROMs and PROMs. Patients undergoing aTSA for AVN were significantly younger than those undergoing RTSA (59 years vs. 73 years, P < .001). At similar follow-up points, the RTSA cohort demonstrated significantly greater improvement in abduction (+51° vs. +32°, P = .03) whereas the aTSA cohort demonstrated significantly greater improvement in internal rotation. Postoperative University of California, Los Angeles scores (30 vs. 27, P = .014) and visual analog scale scores (1.4 vs. 2.4, P = .025) were better after RTSA; however, these differences between prosthesis types did not exceed the minimal clinically important difference. When compared with the control patients, the patients undergoing RTSA for AVN showed similar improvements in all ROMs and PROMs. Similarly, aTSA performed for AVN resulted in comparable improvements in pain, ROMs, and PROMs compared with aTSA performed for primary osteoarthritis. CONCLUSION: RTSA results in similar PROMs to aTSA in the treatment of AVN. Therefore, surgeons should continue to consider other patient factors such as glenoid bone loss and rotator cuff status when selecting implant polarity in patients with AVN.

Preoperative factors associated with loss of range of motion after reverse shoulder arthroplasty.

BACKGROUND: Reverse total shoulder arthroplasty (RTSA) is a successful procedure, often allowing patients to achieve better range of motion (ROM) compared with their preoperative baseline. However, there is a subset of patients who either fail to improve or lose ROM postoperatively. These patients are at increased risk of poor satisfaction and patient-reported outcomes. To date, characteristics of this subset of patients have not been well described. The purpose of this study is to determine risk factors associated with loss of ROM after primary RTSA. METHODS: A retrospective review using a commercial international RTSA database (Exactech Inc., Gainesville, FL, USA) of patients who underwent primary RTSA between 2007 and 2017 was performed. A total of 123 (7.7%) shoulders lost ≥10° of forward elevation (FE) (group 1, P1) and 183 (11.4%) lost ≥10° of external rotation (ER) (group 2, P2). Univariate and multivariate analyses were performed comparing these patients with control cohorts to evaluate risk factors for loss of motion. RESULTS: Better preoperative abduction, FE, ER, and internal rotation were each associated with greater loss of FE (P1 < .001) and ER (P2 < .001) postoperatively. Higher preoperative Simple Shoulder Test (P1 < .001, P2 < .001), Constant (P1 < .001, P2 < .001), Shoulder Pain and Disability Index (P1 < .001, P2 < .001), American Shoulder Elbow Surgeons (P1 < .001), and University of California at Los Angeles (P1 < .001) scores were also strongly associated with loss of ROM postoperatively. Other factors associated with a higher risk of losing ROM included a diagnosis of irreparable rotator cuff tear (P1 = .038), rotator cuff arthropathy (P1 = .017, P2 ≤ .001), and inflammatory arthropathy (P1 = .021). After multivariate analysis, higher preoperative FE (P1 < .001), internal rotation (P1 = -.018), and weight (P1 = .008) remained significant predictors of loss of FE. Better preoperative FE (P2 = .003), ER (P2 < .001), and University of California at Los Angeles score (P2 < .001) remained significant predictors of loss of ER. Patients who lost FE or ER were more likely to report lower satisfaction scores than their counterparts who did not lose ROM (P1 < .001, P2 < .001). CONCLUSION: Patients with greater preoperative shoulder ROM or higher patient-reported outcomes are at higher risk of losing ROM after primary RTSA. They are also at higher risk of reporting lower postoperative satisfaction, though the majority were still satisfied. Surgeons should strongly counsel patients with well-preserved preoperative function on the risk of loss of ROM.

Comparison of survivorship and performance of a platform shoulder system in anatomic and reverse total shoulder arthroplasty.

BACKGROUND: Contemporary studies note sustained clinical benefit and decreasing complications after reverse total shoulder arthroplasty (RTSA), which warrant a comparison with the standard anatomic total shoulder arthroplasty (ATSA). The purpose of this study is to evaluate and compare differences in midterm survivorship between ATSA and RTSA patients treated with a single platform shoulder prosthesis. Secondary objectives include a comparison of the clinical outcomes and complication profile for each procedure. METHODS: A prospective analysis of all primary ATSA and RTSA performed by 3 surgeons between 2007 and 2012 was conducted. Selection of the ATSA or RTSA implant configuration was determined by the surgeons per their clinical understanding of each individual patient's glenoid morphology, rotator cuff, and patient expectations. All 778 procedures were performed using a single platform shoulder system. RESULTS: Survivorship for ATSA was similar to that for RTSA at all time points; ATSA at 2 and 8 years was 98.5% and 96.0%, whereas RTSA at 2 and 8 years was 98.7% and 96.0%, respectively ( P= .392). All postoperative range of motion scores for ATSA patients were greater than those for RTSA patients. The overall rate of complications between the ATSA and RTSA groups was similar (6.3% vs. 4.9%, P= .414). CONCLUSIONS: On the basis of this cohort comparison, both ATSA and RTSA demonstrated similar survivorship at 8 years after surgery with multiple surgeons practicing in different countries. Our results demonstrate that the RTSA and ATSA implants have comparable results and can be expected to provide similar implant longevity over the midterm with excellent functional outcomes.

Anatomic total shoulder arthroplasty after healed rotator cuff repair: a matched cohort.

BACKGROUND: Rotator cuff tears are a common cause of failure after anatomic total shoulder arthroplasty (TSA). The purpose of this study was to evaluate the effect of a healed prior rotator cuff repair (RCR) on outcomes and complications after primary TSA. We hypothesized that patients with a prior healed RCR would have equivalent outcomes and complication rates compared with patients without prior surgery. METHODS: A retrospective review of all primary TSAs with a prior RCR was performed using a multicenter database between 2005 and 2017. Thirty shoulders with prior RCR were case matched on a 3:1 ratio with a minimum 2-year follow-up. Range of motion, strength, patient-reported outcome measures, complications, and reoperations were compared. RESULTS: Thirty shoulders with a prior RCR were compared with 90 control patients without prior surgery at a mean follow-up of 43 months (range, 24-109 months). Groups demonstrated similar preoperative range of motion and patient-reported outcome measures. Postoperatively, TSAs with a prior healed RCR demonstrated less forward flexion (132° vs. 143°, P = .14) and strength (5.7 vs. 6.4 kg, P = .55) compared with control shoulders with no prior surgery; however, these did not meet statistical significance. Complications were significantly more common in patients with a prior RCR (17% vs. 7%, P = .01). Postoperative rotator cuff tears were significantly more common in TSA with a healed prior RCR (13% vs. 1%, P = .014). CONCLUSIONS: TSA after RCR results in similar functional improvements compared with shoulders without prior surgery. However, the risk of a postoperative rotator cuff tear is significantly higher after prior successful RCR. Surgeons should consider this potential complication when indicating these patients for primary TSA.

Methadone and a Clinical Pathway in Adolescent Idiopathic Scoliosis Surgery: A Historically Controlled Study.

STUDY DESIGN: Historically controlled clinical trial. OBJECTIVES: Patients presenting for correction of adolescent idiopathic scoliosis (AIS) by posterior spinal fusion may benefit from structured clinical pathways. We studied the effects of implementing a published clinical pathway for the perioperative care of patients with AIS that required intraoperative use of methadone at our institution. METHODS: We performed a historically controlled clinical trial of patients undergoing posterior spinal fusion for AIS by comparing a retrospectively collected control group of 25 patients with a prospective experimental group of 14 patients receiving methadone, gabapentin, propofol, and remifentanil as part of a new clinical pathway. RESULTS: Use of the pathway decreased average pain scores evaluated by the Numeric Rating Scale in the 24 hours following surgery (4.8 [4-6] to 3.4 [2-4], P = .03 [-2.6 to -0.2; t = -2.3]) and postoperative opioid consumption by 76% (41 [29-51] mg to 10 [4-17] mg, P < .001 [-45 to -15; Welch's t = 4.9]) during the same period. Improved analgesia and reduced reliance on opioids facilitated other postoperative elements of the clinical pathway and shortened the average hospital length of stay by 1 day (4 [3-6] days to 3 [3-5] days, P = .001 [-2 to -1; U = 67, Z = -3.3]). CONCLUSIONS: Multimodal analgesia and a clinical pathway add value in the perioperative care of patients undergoing posterior spinal fusion for AIS by improving analgesia and shortening hospitalization. The prospective arm of the trial was registered at clinicaltrials.gov under NCT02481570.

Patients alter power of breathing as the primary response to changes in pressure support ventilation.

INTRODUCTION: The patient-ventilator relationship is dynamic as the patient's health fluctuates and the ventilator settings are modified. Spontaneously breathing patients respond to mechanical ventilation by changing their patterns of breathing. This study measured the physiologic response when pressure support (PS) settings were modified during mechanical ventilation. METHODS: Subjects were instrumented with a non-invasive pressure, flow, and carbon dioxide airway sensor to estimate tidal volume, respiratory rate, minute ventilation, and end-tidal CO2. Additionally, a catheter was used to measure esophageal pressure and estimate effort exerted during breathing. Respiratory function measurements were obtained while PS settings were adjusted 569 times between 5 and 25 cmH2O. RESULTS: Data was collected on 248 patients. The primary patient response to changes in PS was to adjusting effort (power of breathing) followed by adjusting tidal volume. Changes in respiratory rate were less definite while changes in minute ventilation and end-tidal CO2 appeared unrelated to the change in PS. CONCLUSION: The data indicates that patients maintain a set minute ventilation by adjusting their breathing rate, volume, and power. The data indicates that the subjects regulate their Ve and PetCO2 by adjusting power of breathing and breathing pattern.

Breathing variability predicts the suggested need for corrective intervention due to the perceived severity of patient-ventilator asynchrony during NIV.

Patient-ventilator asynchrony is associated with intolerance to noninvasive ventilation (NIV) and worsened outcomes. Our goal was to develop a tool to determine a patient needs for  intervention by a practitioner due to the presence of patient-ventilator asynchrony. We postulated that a clinician can determine when a patient needs corrective intervention due to the perceived severity of patient-ventilator asynchrony. We hypothesized a new measure, patient breathing variability, would indicate when corrective intervention is suggested by a bedside practitioner due to the perceived severity of patient-ventilator asynchrony. With IRB approval data was collected on 78 NIV patients. A panel of experts reviewed retrospective data from a development set of 10 NIV patients to categorize them into one of the three categories. The three categories were; "No to mild asynchrony-no intervention needed", "moderate asynchrony-non-emergent corrective intervention required", and "severe asynchrony-immediate intervention required". A stepwise regression with a F-test forward selection criterion was used to develop a positive linear logic model predicting the expert panel's categorizations of the need for corrective intervention. The model was incorporated into a software tool for clinical implementation. The tool was implemented prospectively on 68 NIV patients simultaneous to a bedside practitioner scoring the need for corrective intervention due to the perceived severity of patient-ventilator asynchrony. The categories from the tool and the practitioner were compared with the rate of agreement, sensitivity, specificity, and receiver operator characteristic analyses. The rate of agreement in categorizing the suggested need for clinical intervention due to the perceived presence of patient-ventilator asynchrony between the tool and experienced bedside practitioners was 95% with a Kappa score of 0.85 (p < 0.001). Further analysis found a specificity of 84% and sensitivity of 99%. The tool appears to accurately match the suggested need for corrective intervention by a bedside practitioner. Application of the tool allows for continuous, real time, and non-invasive monitoring of patients receiving NIV, and may enable early corrective interventions to ameliorate potential patient-ventilator asynchrony.

Clinical decision support recommending ventilator settings during noninvasive ventilation.

NIV therapy is used to provide positive pressure ventilation for patients. There are protocols describing what ventilator settings to use to initialize NIV; however, the guidelines for titrating ventilator settings are less specific. We developed an advisory system to recommend NIV ventilator setting titration and recorded respiratory therapist agreement rates at the bedside. We developed an algorithm (NIV advisor) to recommend when to change the non-invasive ventilator settings of IPAP, EPAP, and FiO2 based on patient respiratory parameters. The algorithm utilized a multi-target approach; oxygenation, ventilation, and patient effort. The NIV advisor recommended ventilator settings to move the patient's respiratory parameters in a preferred target range. We implemented a pilot study evaluating the usability of the NIV advisor on 10 patients receiving critical care with non-invasive ventilation (NIV). Respiratory therapists were asked their agreement on recommendations from the NIV advisor at the patient's bedside. Bedside respiratory therapists agreed with 91% of the ventilator setting recommendations from the NIV advisor. The POB and VT values were the respiratory parameters that were most often out of the preferred target range. The IPAP ventilator setting was the setting most often considered in need of changing by the NIV advisor. The respiratory therapists agreed with the majority of the recommendations from the NIV advisor. We consider the IPAP recommendations informative in providing the respiratory therapist assistance in targeting preferred POB and Vt values, as these values were frequently out of the target ranges. This pilot implementation was unable to produce the results required to determine the value of the EPAP recommendations. The FiO2 recommendations from the NIV advisor were treated as ancillary information behind the IPAP recommendations.

Acceptance of a propofol and remifentanil infusion dosing algorithm to optimize postoperative emergence and analgesia.

We implemented a pharmacokinetic/pharmacodynamic (PK/PD) based optimization algorithm recommending intraoperative Remifentanil and Propofol infusion rates to minimize time to emergence and maximize the duration of analgesia in a clinical setting. This feasibility study tested the clinical acceptance of the optimization algorithm's recommendations during scoliosis surgical repair for 14 patients. Anesthesiologist accepted 359/394 (91%) of the recommendations given on the basis of the optimization algorithm. While following the optimization's recommendations the anesthesiologist decreased Propofol infusions from an average of 164-135 mcg/kg/min [p = 0.002] and increased Remifentanil infusions from an average of 0.22-0.30 mcg/kg/min [p = 0.004]. The anesthesiologists appeared to accept and follow the recommendations from a PK/PD based optimization algorithm.

Optimizing intraoperative administration of propofol, remifentanil, and fentanyl through pharmacokinetic and pharmacodynamic simulations to increase the postoperative duration of analgesia.

Titrating an intraoperative anesthetic to achieve the postoperative goals of rapid emergence and prolonged analgesia can be difficult because of inter-patient variability and the need to provide intraoperative sedation and analgesia. Modeling pharmacokinetics and pharmacodynamics of anesthetic administrations estimates drug concentrations and predicted responses to stimuli during anesthesia. With utility of these PK/PD models we created an algorithm to optimize the intraoperative dosing regimen. We hypothesized the optimization algorithm would find a dosing regimen that would increase the postoperative duration of analgesia, not increase the time to emergence, and meet the intraoperative requirements of sedation and analgesia. To evaluate these hypotheses we performed a simulation study on previously collected anesthesia data. We developed an algorithm to recommend different intraoperative dosing regimens for improved post-operative results. To test the post-operative results of the algorithm we tested it on previously collected anesthesia data. An anesthetic dataset of 21 patients was obtained from a previous study from an anesthetic database at the University of Utah. Using the anesthetic records from these surgeries we modeled 21 patients using the same patient demographics and anesthetic requirements as the dataset. The anesthetic was simulated for each of the 21 patients with three different dosing regimens. The three dosing regimens are: from the anesthesiologist as recorded in the dataset (control group), from the algorithm in the clinical scenario one (test group), and from the algorithm in the clinical scenario two (test group). We created two clinical scenarios for the optimization algorithm to perform; one with normal general anesthesia constraints and goals, and a second condition where a delayed time to emergence is allowed to further maximize the duration of analgesia. The algorithm was evaluated by comparing the post-operative results of the control group to each of the test groups. Comparing results between the clinical scenario 1 dosing to the actual dosing showed a median increase in the duration of analgesia by 6 min and the time to emergence by 0.3 min. This was achieved by decreasing the intraoperative remifentanil infusion rate, increased the fentanyl dosing regimen, and not changing the propofol infusion rate. Comparing results between the clinical scenario 2 dosing to the actual dosing showed a median increase in the duration of analgesia by 26 min and emergence by 1.5 min. To dosing regimen from clinical scenario 2 greatly increased the fentanyl dosing regimen and greatly decreased the remifentanil infusion rate with no change to the propofol infusion rate. The results from this preliminary analysis of the optimization algorithm appear to imply that it can operate as intended. However a clinical study is warranted to determine to what extent the optimization algorithm determined optimal dosing regimens can maximize the postoperative duration of analgesia without delaying the time to emergence in a clinical setting.

Decision support system facilitates rapid decreases in pressure support and appropriate inspiratory muscle workloads in adults with respiratory failure.

PURPOSE: A commercially available decision support system (DSS) provides guidance for setting inspiratory pressure support (PS) to maintain work of breathing (WOB/min), breathing frequency (f), and tidal volume (VT) in proper clinical ranges (VentAssist™). If these values are outside the proper clinical range patients may suffer fatigue, atrophy, hypoventilation, hyperventilation, volutrauma, or VT deficiency. The purpose of our study was to evaluate the increase of the percentage of breaths in the targeted clinical ranges when the DSS guidance for setting the PS was followed. MATERIALS AND METHODS: The study included 43 intubated adults with respiratory failure in an academic medical intensive care unit. Each of the patients had received ventilatory support for >24h with no weaning trials attempted. Clinicians switched the ventilator to PS then proceeded to utilize the guidance recommended by the DSS for setting PS for 21 patients (intervention group); while the clinicians caring for the remaining 23 patients did not have access to the DSS (control group). RESULTS: The use of a DSS to set PS level increased the percentage of breaths in the targeted clinical range [28% to 48%, p value<0.0001]. An unexpected result was that while following the DSS 18 of the 21 patients were rapidly weaned to minimal ventilator settings within 46±38min; however, when the DSS was not available weaning to minimal ventilator settings lasted 21±12h [p value<0.0001]. CONCLUSIONS: The DSS is successful at assisting clinicians on how to set PS specific to a patient's individual demands (VT and f) while accounting for their breathing effort (WOB/min). The DSS appears to promote rapid weaning of PS to minimal ventilator settings when appropriate.