Tuesday, October 27, 2020

Is it safe to operate on patients with obesity?

 Level of Obesity is Directly Associated with Complications Following Arthroscopic Rotator Cuff Repair


These authors investigated the association between increasing levels of obesity and postoperative complications within 30 days of arthroscopic rotator cuff repair.



18,521 patients who underwent arthroscopic rotator cuff repair (ARCR) from 2015-2017were identified in the American College of Surgeons National Surgical Quality Improvement and stratified into three cohorts according to their body mass index (BMI). Patients with BMI <30 kg/m2 were placed in the nonobese cohort, patients with BMI between 30-40 kg/m2 were placed in the obese cohort, and patients with BMI >40 kg/m2 were placed in the morbidly obese cohort. 9,548 (51.6%) of the patients were nonobese, 7,438 (40.2%) were obese, and 1,535 (8.3%) were morbidly obese. 


Multivariate logistic regression was employed to investigate the relationship between increasing levels of obesity and postoperative complications within 30 days of surgery.


Among nonobese, obese, and morbidly obese patients showed increasing rates of complications.




In comparison to nonobese patients, multivariate analysis identified both obesity and morbid obesity as significant predictors of medical complications (OR 1.72; OR 2.16), pulmonary complications (OR 2.66; OR 4.06), and overall complications (OR 1.52; OR 1.77).


Among obese patients undergoing ARCR, functional dependence, COPD, steroid use, and diabetes were identified as comorbidities which also increased the risk of short-term complications.



Comment: These results are important. It seems reasonable to expect that the same risk profile for medical complications would apply to other surgeries, such as arthroplasty. 


The authors refer to obesity as a "modifiable" risk factor. It is, however, unclear how modifiable obesity is and whether having the patient shed some pounds will increase the safety of shoulder surgery.


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To see our new series of youtube videos on important shoulder surgeries and how they are done, click here.

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. Also see the essentials of the ream and run.

Use the "Search" box to the right to find other topics of interest to you.

You may be interested in some of our most visited web pages   arthritis, total shoulder, ream and runreverse total shoulderCTA arthroplasty, and rotator cuff surgery 


Monday, October 26, 2020

Reverse total shoulder - early complications

Reverse total shoulder arthroplasty clinical and patient-reported outcomes and complications stratified by pre-operative diagnosis: a systematic review


These authors sought to investigate differences in clinical and patient reported outcomes (PROs), and complication type and rate amongst preoperative diagnoses following reverse total shoulder arthroplasty: rotator cuff tear arthropathy (CTA), primary osteoarthritis (OA), massive irreparable rotator cuff tear (MIRCT), proximal humeral fracture (PHFx), rheumatoid arthritis (RA), and revision of anatomic arthroplasty (Rev).


They searched three electronic databases for patients with (1) minimum 60 years of age with RTSA for the preoperative diagnoses; (2) minimum 2-year follow-up; (3) pre- and postoperative values for clinical and PROs


Fifty-three studies were included: 36 (68%) were level IV retrospective case series. 33 (62%) demonstrated high risk of bias on the MINORS tool, and the 3 randomized controlled trials demonstrated a low risk of bias on Modified Downs and Black. 


RTSA improved clinical and PROs for all preoperative diagnoses. Revisions had poorer final outcomes as noted by lower ASES (69) and pain score (1.8) compared to other preoperative diagnoses (78-82 and 0.4-1.4). 





The highest overall rate of complications was seen in the RA group with a rate of 28%. RA also had the highest rate of each type of complication with 41% having acromial or scapular spine fractures, 28% infections, 26% dislocations, and 10% nerve palsy. 


The lowest overall complication rate was seen in the OA group (1.4%) followed by the CTA group (7.4%). 



The PHFx aggregated rate for each category of complications was less than 2%. 


The most frequently occurring complication in the Rev and MIRCT groups was glenoid loosening (4% and 6.7%, respectively). It is unclear why the outcomes for MIRCT were worse than for other primary diagnoses.


Dislocation was reported as a complication in less than 2% for all preoperative diagnoses with the exception of RA.


They concluded that the RTSA literature is at high risk of bias.


To see our technique for reverse total shoulder, click on this link.

To support our research to improve outcomes for patients with shoulder problems, click here.

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How you can support research in shoulder surgery Click on this link.

To see our new series of youtube videos on important shoulder surgeries and how they are done, click here.

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. Also see the essentials of the ream and run.

Use the "Search" box to the right to find other topics of interest to you.

You may be interested in some of our most visited web pages   arthritis, total shoulder, ream and runreverse total shoulderCTA arthroplasty, and rotator cuff surgery 






Rotator cuff injury - how to measure shoulder function and functional improvement.

The Western Ontario Rotator Cuff Index Normative Values for Age and Gender


These authors sought to determine determine normative values for the Western Ontario Rotator Cuff Index (WORC) values and assess whether the WORC needs an adjusted score for age- and gender. 

The WORC questionnaire consists of 21 items divided in 5 domains. The 5 domains are physical symptoms (1), sports and recreation (2), work (3), social function (4), and emotional disability (5). Each item is scored on a 100-mm scale, ranging from 0 (best) to 100 (worst). Of note is that this inverted scale can create confusion because the worst values are "100". Thus they had to use a formula to convert the total and domain scores into percentages, with 0% as the lowest functional status level and 100% the highest, to allow easy clinical applicability.


The mean total  WORC score was 94 (±9) and the mean total WORC score in every age and gender category was > 90%. Of all participants, 85% scored between 91%-100%, 63 participants (15%) scored 100%.


They found no statistically significant differences between genders in the overall score, domain scores and within the age categories.


Comment: Patient-reported measures (PRM's) are the essential element of assessing the status of the shoulder before and sequentially after treatment. While some surgeons use the "adjusted" Constant score, age and sex adjustments are not necessary as long as patients are appropriately stratified according to the question being asked, e.g. "are women with supraspinatus tears less functional than men?" or "are patients <50 yrs with supraspinatus tears less functional than patients> 50?"


For measuring functional improvement for each patient, a very simple metric can be used with any PRM: the percent of maximum possible improvement (%MPI). The math is easy:


(postoperative PRM minus preoperative PRM)/(perfect PRM minus preoperative PRM). 


The %MPI avoids the issues of determining different "MCIDs" (minimal clinically important differences) for different patient populations, different diagnoses and different procedures.


To support our research to improve outcomes for patients with shoulder problems, click here.

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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

Use the "Search" box to the right to find other topics of interest to you.

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




Saturday, October 24, 2020

Shoulder arthroplasty: should patients be placed on low-dose aspirin?

Low-Dose Aspirin and the Rate of Symptomatic Venous Thromboembolic Complications Following Primary Shoulder Arthroplasty

These authors conducted a review ofcomplications occurring within 90 days of 2,394 primary shoulder arthroplasties performed over a three-year period.


Patients were preoperatively risk stratified into medically high, moderate or low risk as part of a standardized navigated care pathway. 81 mg ASA (low-dose) was routinely used once daily for 6 weeks for chemoprophylaxis unless alternative medications were deemed necessary by the medical team. 


Symptomatic venous thromboembolism (VTE) occurred following 0.63% (15/2,394) of primary shoulder arthroplasties. 


There were 9 patients with deep vein thrombosis (DVT) and 6 with pulmonary emboli (PE). 


81 mg ASA was utilized in 2,141 (89.4%) of patients, which resulted in an overall VTE rate of 0.56%. 


Medically high-risk patients were significantly more likely to have a VTE (P = .018). Patients with a history of prior DVT, asthma and cardiac arrhythmias were significantly more likely to have a VTE (P < .05). 



A total of 5 bleeding related complications in the entire cohort. Among patients treated with low-dose ASA for VTE prophylaxis, 4/2,141 (0.19%) had a postoperative hematoma that underwent aspiration in the office. Two of these patients required more than one aspiration and two patients ultimately returned to the operating room for an additional intervention. One patient initially treated with RSA had a hematoma evacuation and polyethylene exchange. The other patient developed a superficial infection from repeated hematoma aspiration and required surgical irrigation and d├ębridement. One patient with a history of atrial fibrillation who received a novel oral anticoagulant medication (dabigatran) postoperatively developed a bleeding esophageal ulcer that required surgical intervention to control. Of the patients who were diagnosed with a VTE, bleeding complications secondary to VTE treatment occurred in 1/15 (6.7%).


Comment: Both VTE and bleeding are potentially serious complications of shoulder arthroplasty. This study examined the effectiveness and risks of low dose ASA as a prophylactic strategy. The manuscript does not present the location of the venous thromboses observed (lower extremity, surgical upper extremity, contralateral upper extremity). This information may be helpful in understanding the role of non-pharmacologic approaches, such as sequential lower extremity compression, early ambulation, compressive stockings. 


The increase risk of patients with prior DVT or cardiac disease is understandable. The increased risk of patients with asthma is unexplained.


Our approach to total shoulder arthroplasty can be viewed by clicking here.


To support our research to improve outcomes for patients with shoulder problems, click here.

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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

Use the "Search" box to the right to find other topics of interest to you.

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



Rehabilitation after a ream and run - the importance of a quick start

The final range of motion achieved by patients after a ream and run is largely determined by the success of their exercises in the first week.

Here are some examples of three key exercises by a patient one week after a left ream and run.

The pulley

The forward lean / table slide
The supine stretch


The complete ream and run rehab program can be seen in this link.

To support our research to improve outcomes for patients with shoulder problems, click here.

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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

Use the "Search" box to the right to find other topics of interest to you.

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

Thursday, October 22, 2020

Periprosthetic infections - the critical role of slime (biofilms) on the implants

 Methylene Blue Is an Effective Disclosing Agent for Identifying Bacterial Biofilms on Orthopaedic Implants

While this article concerns the use of methylene blue to indicate the presence of bacterial biofilms on implant surfaces, it also provides a useful review of the role of biofilms in periprosthetic infections (PJI). With respect to the shoulder it is recognized that the organism most commonly causing PJI, Cutibacterium, avidly forms biofilms on the most commonly used implant material, titanium alloy. See this link and this link.


The term 'biofilm' refers to bacteria embedded in an extracellular slime layer consisting of polysaccharides, extracellular DNA, proteins and lipids. Biofilms can develop channels allowing for diffusion of nutrients to the embedded bacteria. Because of the limited ability of oxygen to enter, the biofilm provides a range of environments from aerobic on the surface to anaerobic at the depth. Spatial separation of metabolic environments allows for niches for different types of bacteria. Bacteria in biofilms behave differently from those in the free-floating (planktonic) form.

Biofilms can form on all orthopaedic implants, including metal, plastic, and cement. They can be found in fibrous membranes surrounding implants. Because they are viscoelastic liquids, they can resist detachment and can flow across surfaces.

Biofilms protect bacteria from host defenses (1) forming conglomerates too large for phagocytosis by inflammatory cells and  (2) blocking antibodies from diffusing in to reach the bacteria. They also protect the bacteria from antibiotics such that the levels a 1000 times greater concentration is required to kill bacteria in biofilms in comparison to planktonic bacteria.

Biofilms make bacteria difficult to recover. Even though a prosthesis has a bacteria-ladened biofilm, joint fluid aspiration may well be negative because the bacteria are not present in the fluid. Bacteria in biofilms are not easily recovered because conventional culturing methods may not dislodge the biofilm. Even if the biofilm is recovered, host factors such as endonucleases may prevent the bacteria from growing. Bacteria in biofilms may enter a dormant or slow growing phenotype that grows slowly or not at all in cultures.

Essentially all periprosthetic infections involve biofilms. These can progress very slowly and may be non-symptomatic for years. Biofilm infections may exert their pathological effects by triggering insidious tissue damage (such as bone resorption) rather than by creating the usual signs of inflammation. Thus it may be very difficult to differentiate prosthetic loosening from the chronic effects of a biofilm from 'aseptic' mechanical loosening. These infections do not resolve spontaneously and usually require surgical debridement and antibiotics.

Biofilms may serve as sources of more obvious planktonic infection if the biofilm is stimulated or if the host is weakened.

These observations regarding biofilms have informed our current approach to failed shoulder arthroplasty.


To support our research to improve outcomes for patients with shoulder problems, click here.

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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

Use the "Search" box to the right to find other topics of interest to you.

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


Wednesday, October 21, 2020

Revision shoulder arthroplasty - risk of nerve injury

Incidence of Peripheral Nerve Injury in Revision Total Shoulder Arthroplasty: An Intraoperative Nerve Monitoring Study

Complication rates for primary anatomic (aTSA) and reverse TSA (rTSA) have been cited to be as high as 20%. Revision following aTSA and rTSA occurs in 7.5%-16.3% cases. The complication rates for revision surgery can be as high as 50%.


The incidence of nerve injury following primary TSA has been cited at 1-18.7% and may actually be higher as suggested by studies performed utilizing electromyography in the postoperative period.


Most of these injuries are thought to be related to inadvertent traction and stretching of the brachial plexus during intra-operative positioning/manuevering. Other mechanisms include injury secondary to surgical dissection, laceration, instrumentation, interscalene block anesthesia, lengthening of the limb vascular injury and/or compression secondary to hematoma formation and/or retractor use.


These authors reported their experience with continuous intraoperative nerve monitoring in patients having revision arthroplasty for  infection (N=7), failed total and hemi-arthroplasty secondary to pain, dysfunction and/or loose components (N=36), and a periprosthetic fracture (N=1). 


Thirty-two patients were revised to a reverse ( rTSA), six to an anatomic (aTSA) and six had a spacer placed. 


The protocol for monitoring is extensive, utilizing a neurophysiologist in the operating room and a remote neuromonitoring professional remotely. Nerve monitoring data included transcranial electrical motor evoked potentials (MEPs), somatosensory evoked potentials (SSEPs), and free-run electromyography (EMG). Subdermal electrodes for stimulation and recording were placed in the non-operative arm by the technician while the operative arm electrodes were positioned by the surgeon following draping and preparation of the surgical extremity. Two electrodes were placed in each muscle approximately 2 cm apart for differential channel recordings. The muscles recorded in the operative arm included all three heads of the deltoid, biceps brachii, extensor carpi radialis (ECR), abductor pollicis brevis (APB) and the first dorsal interosseous (FDI) or abductor digiti minimi (ADM) to assess the axillary, musculocutaneous, radial, median and ulnar nerves, respectively. The electrodes were inserted into the belly of the muscle to maximize recording the compound action potential. SSEP stimulating electrodes were placed superficially over the median and ulnar nerves in the operative arm. The distal ulnar and median nerves have relatively large afferent somatosensory components and stimulation of these nerves are known to produce large monitorable SSEPs. In contrast, reliable SSEPs cannot be obtained from axillary, musculocutaneous nerves under general anesthesia. MEP Alerts were defined as reduction in signal of 80% in from an individual muscle recording, except for deltoid muscle alerts which required all three heads to have a signal reduction of 80% to define an alert. 


In the case of an alert, the operating surgeon was immediately notified.  Patient extremity was returned to neutral position, retractors were removed, and a 2-3-minute surgical pause was performed.


22.4% of procedures (n=10) had a transcranial electrical motor evoked potential (MEPs) alert with eight isolated to a single nerve (seven axillary, one radial) and one isolated to the axillary and musculocutaneous nerves. 


One patient experienced a major brachial plexus alert involving axillary, musculocutaneous, radial, ulnar, and median nerve MEP alerts as well as ulnar and median nerve somatosensory evoked potentials (SSEPs), alerts. 


Age, gender, BMI, CCI, and preoperative ROM were not found to be significantly different between cases in which a MEP occurred compared to those with no MEP. There were zero minor or major nerve injuries found in the postoperative period, while four (9.1%) developed distal peripheral neuropathy (DPN).


Comment: The nerves around the shoulder are at increased risk for injury during revision arthroplasty. The tissues around the shoulder are scarred with obliteration of the normal planes.  Dissection can be difficult, so that reference to reliable landmarks is important. 




The joint is often stiff, so that during surgical mobilization the nerves may experience a stretch exceeding what they've been used to. Substantial retraction may be necessary to expose the implants. Nerves can be scarred to the surrounding tissues.


One approach, as detailed in this report, is to use intraoperative nerve monitoring (IONM). The article does not present the cost of the personnel, supplies and equipment or the time IONM adds to the procedure. 


Another approach, the one we use, is to limit the time during which the shoulder is held in extreme positions (i.e. those substantially different from the preoperative range) and to limit the time during which vigorous retraction is applied. Thus we "give the nerves a drink", returning the arm to a neutral position and relieving pressure on the retractors, every ten minutes or so.  Because we do not use inter scalene blocks, we can document the integrity of the brachial plexus immediately after surgery. 


It is not clear that surgeons using IONM have lower rates of nerve injury than those who do not.


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To see a YouTube of our technique for total shoulder arthroplasty, click on this link.

To support our research to improve outcomes for patients with shoulder problems, click here.

To subscribe to this blog, enter your email in the box to your right that looks like the below



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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

Use the "Search" box to the right to find other topics of interest to you.

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