The value of outpatient shoulder arthroplasty and selection bias

 Safety and Cost Effectiveness of Outpatient Total Shoulder Arthroplasty: A Systematic Review

These authors conducted a systematic review of patient selection, perioperative protocols, complications, costs, patient satisfaction, and clinical outcomes of outpatient total shoulder TSA and compared these with inpatient total shoulder TSA.

Their review identified 25,808 and 231,408 patients undergoing outpatient and inpatient TSA, respectively. 

Patient selection for outpatient TSA was based on patient age, medical comorbidities, social support, living proximity to location of surgery where emergency care is available.

Common criteria for outpatient arthroplasty included

    age younger than 70 years

    no evidence of preoperative anemia or previous venous thromboembolism

    no chronic obstructive pulmonary disease; no uncontrolled sleep apnea

    no cardiac comorbidities (no heart failure, no anticoagulation use and two or fewer cardiac stents).

    no pacemaker or defibrillator

    no opioid dependence 

    no hypertension or diabetes

    no bleeding disorder, dialysis, cancer

    no peripheral vascular disease

    no depression

    no chronic anemia

    approval for outpatient surgery by  anesthesia staff

    adequate social support

    close proximity of residence to the hospital or ASC

    ASA Physical Status scores of 3 or less

Readmission rates were similar between inpatients and outpatients, with one study finding more readmissions after inpatient TSA. 

Five studies found that patients having outpatient TSA were at a lower risk of overall complications,and

shoulder-related complications (eg, dislocation, manipulation under anesthesia, surgical site infection, capsulitis, and hematoma).

Three articles discussed reasons for outpatient readmissions; medical complications (n = 57, 67.0%), implant-related complications (n = 17, 20.0%), and uncontrolled pain (n = 11, 13.0%) were the most common. 

Five studies found no statistical difference in ED visits between outpatient and inpatient TSA. 

Ten studies, with 446 outpatient TSAs found that only six patients (1.3%) having outpatient arthroplasty required an unplanned overnight stay.

Reasons for failed outpatient surgery were surgery delays,  patient convenience, hypoxia and not meeting postanesthesia care unit (PACU) discharge criteria.

Outpatient TSA demonstrated a charge reduction of $25,509 to $53,202 per patient. One study found  that a bundled payment program in an ambulatory surgery center reduced total charges of care, mainly through reduced implant charges ($42,410 versus $44,530, P = 0.024).

Patient satisfaction after outpatient TSA was “good to excellent” in more than 95% of patients.

Comment: It is apparent that the successful implementation of an outpatient arthroplasty program requires dedication to a carefully delineated patient selection program, a well organized approach to preoperative education, anesthesia, postoperative pain management, and infrastructure to support patients that may have postoperative difficulties. It also requires thoughtful scheduling, in that a patient having early morning surgery is more likely to be ready for same day discharge than a person having arthroplasty in the late afternoon.

Performance of arthroplasty in an ambulatory surgery center may enable cost-saving negotiations, such as implant cost - the principal driver of arthroplasty expense.

Finally, there may be other selection bias effects of outpatient vs inpatient arthroplasty. It seems possible that patients having outpatient surgery would be more likely to have commercial insurance, to have higher household incomes, to have better family support, and to be better educated - each of which is likely to be associated with better outcomes. While these patient characteristics were not investigated in this study, it seems important that they be included in future studies.

If outpatient surgery enables lower implant costs and selects for socially advantaged patients who are likely to have better outcomes, the value (benefit/cost) will be appear to be greater for ambulatory surgery. These effects should be controlled for in comparative studies.

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Here are some videos that are of shoulder interest

Shoulder arthritis - what you need to know (see this link)

Shoulder arthritis - x-ray appearance (see this link)

The smooth and move for irreparable cuff tears (see this link)

The total shoulder arthroplasty (see this link).

The ream and run technique is shown in this link.

The cuff tear arthropathy arthroplasty (see this link).

The reverse total shoulder arthroplasty (see this link).

Shoulder rehabilitation exercises (see this link).

This is a non-commercial site, the purpose of which is education, consistent with "Fair Use" as defined in Title 17 of the U.S. Code.          

Note that author has no financial relationships with any orthopaedic companies.

Shoulder arthritis in patients under 60 years - how should it be treated?

Mid- to long-term follow-up of shoulder arthroplasty for primary glenohumeral osteoarthritis in patients aged 60 or under

These authors conducted a retrospective multicenter study all aged 60 years or less undergoing either hemiarthroplasty (HA) or total shoulder arthroplasty (TSA) for primary glenohumeral osteoarthritis with aminimum of 24-month follow-up.

202 patients with a mean age of 55.3 years (range, 36-60 years) underwent TSA with a mean follow-up of 9 years (range, 2-24.7 years).  Revision arthroplasty was performed in 33 (16.3%) shoulders, with glenoid failure associated with the revision in 29 shoulders (88%). Survivorship analysis demonstrated 95% free of revision at 5 years, 83% at 10 years, and 60% at 20-year follow-up. 

31 patients with a mean age of 52.5 years (range, 38-60 years) underwent HA with a mean followup of 8.7 years (range, 2-21.4 years). Revision arthroplasty was performed in 5 (16.1%) shoulders, with glenoid erosion as the cause for revision in 4 shoulders (80%). HA survivorship analysis demonstrated 84% free from revision at 5 years and 79% at the final follow-up. 

The survival curves for the two groups are shown below.

Comment: One of the big questions regarding retrospective studies such as this is "why did surgeons elect HA in 31 of the 233 patients with primary arthritis?" While the article did not discuss the risk of selection bias in the limitations section, this confounder needs to be considered. Could it be that this selection was made because the surgeons performing these 31 cases were uncomfortable with at TSA in these cases or because the pathoanatomy precluded use of a glenoid? A hint may be gained by comparing the glenoid types in the two groups. From the chart below, it is evident that the hemiarthroplasty group contained a disproportionate percentage of the difficult type C glenoids and proportionately fewer of the relatively easy type B1 glenoids. 

The reader would also be interested comparing the preoperative Constant Scores for both groups. While these data are available for the TSA group:

comparable data are not provided for the HA group, in spite of the title of Table III:

While this article provides additional data that the glenoid is the "weak link" in shoulder arthroplasty, it does not appear to provide data useful for comparing and contrasting TSA and HA in similar patients.

The importance of recognizing the influence of patient selection is demonstrated below

Ream and run and total shoulder: patient and shoulder characteristics in five hundred forty-four concurrent cases

These authors use two different types of joint replacement to treat cases of shoulder arthritis with intact rotator cuffs.

One is a conventional total shoulder that covers the glenoid with a plastic socket that matches the metal humeral head component (TSA).  

The other is a ream and run in which the glenoid is reamed to the shape that matches the metal humeral head component (RnR).

The decision between the two options is made by the patient and the surgeon after a thorough discussion of the pros and cons of each method for the individual patient. 

These authors analyzed the patient characteristics, shoulder characteristics, and two year clinical outcomes of 544 patients having RnR or TSA at the same institution during the same six year period.

Patients having the RnR were more likely to be male (92.0% vs. 47.0%), younger (58 ± 9 vs. 67 ± 10 years), married (83.2% vs. 66.8%), from outside of the authors' state (51.7% vs. 21.7%), commercially insured (59.1% vs. 25.2%), and to have type B2 glenoids (46.0% vs. 27.8%) as well as greater glenoid retroversion (19 ± 11 vs. 15 ± 11 degrees) (p < .001). 

The average two year SST score for the RnRs was 10.0 ± 2.6 vs. 9.5 ± 2.7 for the TSAs. The percent of maximum possible improvement (%MPI) for the RnRs averaged 72 ± 39% vs. 73 ± 29% for the TSAs. 

Patients with work-related shoulder problems had lower two year SSTs and lower %MPIs. Younger patients having TSAs did less well than older patients.

Female patients having RnRs did less well than those having TSAs (p < 0.001).

Forty-seven patients (9%) had a second procedure within the study period.

Among the 281 patients having a TSA, 13 (5%) had repeat procedures during the period of this study. The average age at the index total shoulder arthroplasty for the patients having a second procedure after a total shoulder was 57 ± 13 years, ten years younger that the average age of 67 ± ten years at the index TSA for those not having a second procedure (p = 0.002). Seven of the 13 (54%) patients having a second procedure after a TSA were female while 142 of the 268 (53%) not having a second procedure were female (p = 0.954). Six TSAs (2%) had a closed manipulation under anesthesia at an average of 15 weeks after their index arthroplasty. Two patients (1%) had arthroscopic procedures at other institutions— details of these arthroscopies were not available. Five patients (2%) had an open procedure at an average of six months after their index arthroplasty; these included two subscapularis repairs and three prosthetic revisions. Intra-operative cultures were obtained in three (60%) of these open revisions; none were positive.

Among the 263 patients having a ream and run procedure, 34 (13%) had a second procedure during the study period. The average age of the patients having a second procedure after a ream and run was 55 ± ten years in comparison to 58 ± nine years for the group not having a second procedure (p = 0.018). Seven (21%) of the 34 patients having a second procedure were female in comparison to 14 (6%) of the 229 ream and run patients not having a second procedure (p = 0.004). Twenty (8%) had a closed manipulation under anaesthesia at an average of 22 weeks after their index arthroplasty. Fourteen patients (5%) had an open procedure at an average of 15 months after their index arthroplasty; these included six exchanges of the humeral head component with soft tissue release, five complete single stage humeral component exchanges without additional glenoid surgery, and three conversions to a total shoulder. Intra-operative tissue and explant cultures were obtained in 12 (86%) of these open revisions; seven (58%) of these cultures were positive for Propionibacterium (Cutibacterium). All patients with positive cultures were males with the initial diagnosis of osteoarthritis; the average age (±SD) of these patients was 54 ± ten years.
The authors concluded that excellent outcomes can be achieved for appropriately selected patients having either procedure. They noted that the RnR was used more commonly for more severe pathology (i.e. type B2 and retroverted glenoids).

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We have a new set of shoulder youtubes about the shoulder, check them out at this link.

Be sure to visit "Ream and Run - the state of the art" regarding this radically conservative approach to shoulder arthritis at this link and this link

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How you can support progress in shoulder surgery

You may be interested in some of our most visited web pages arthritis, total shoulder, ream and run, reverse total shoulder, CTA arthroplasty, and rotator cuff surgery as well as the 'ream and run essentials'