Tuesday, February 23, 2021

How to secure the humeral component safely and securely

An impaction grafted standard length humeral stems provides secure fixation that preserves bone, enables the use of eccentric head components of different thickness, avoids stress shielding and fracture, and permits easy removal should revision become necessary. 

Impaction grafting effectively manages the challenge of the variable medullary anatomy of the humerus (which cannot be matched by any prosthesis), while avoiding the problem of endosteal notching.




Here are some videos that are of shoulder interest
Shoulder arthritis - what you need to know (see this link).
How to x-ray the shoulder (see this link).
The ream and run procedure (see this link).
The total shoulder arthroplasty (see this link).
The cuff tear arthropathy arthroplasty (see this link).
The reverse total shoulder arthroplasty (see this link).
The smooth and move procedure for irreparable rotator cuff tears (see this link).
Shoulder rehabilitation exercises (see this link).



Monday, February 22, 2021

Postoperative glucose control may lower risk of periprosthetic infection

 Is postoperative glucose variability associated with adverse outcomes following shoulder arthroplasty?

These authors investigated the association between postoperative glycemic variability and short-term complications for 1074 patients having total shoulder arthroplasty (TSA) and reverse total shoulder arthroplasty (RTSA).


The mean patient age was 70 years, and 40% (!) of patients had a preoperative diagnosis of diabetes mellitus. 


A postoperative infection developed in 3 of 636 (0.5%) patients without diabetes compared with 9 of 424 (2.1%) patients with diabetes. Younger patient age and a preoperative diagnosis of diabetes mellitus showed statistically significant associations with postoperative infection. 


The first in-hospital glucose measurement beyond the reference tertile of 70-140 mg/dL showed a statistically significant association with postoperative infection,  whereas the second and third glucose measurements showed no association with postoperative infection.


The authors suggest that in-hospital glycemic control, as well as preoperative glycemic control and optimization, may be beneficial for reducing postoperative infections following shoulder arthroplasty.


Comment: Glycemic control before and immediately after shoulder arthroplasty may hold promise as modifiable risk factors for infection.


Interested readers should also view this related post When is a patient with diabetes safe for arthroplasty surgery?


Here are some videos that are of shoulder interest
Shoulder arthritis - what you need to know (see this link).
How to x-ray the shoulder (see this link).
The ream and run procedure (see this link).
The total shoulder arthroplasty (see this link).
The cuff tear arthropathy arthroplasty (see this link).
The reverse total shoulder arthroplasty (see this link).
The smooth and move procedure for irreparable rotator cuff tears (see this link).
Shoulder rehabilitation exercises (see this link).

Glenoid reaming can generate enough heat to kill bone - relevance to total shoulder and ream and run arthroplasty

Thermal effects of glenoid reaming during shoulder arthroplasty in vivo

These authors point out that 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. They 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, they hypothesized that irrigation of the glenoid during reaming can reduce this temperature increase. They used real-time, high-definition, infrared thermal video imaging 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.

The 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. 

The 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).

They concluded that 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.


These authors suggest that inaccurate reaming and thermal osteonecrosis from heat generated during the reaming process may contribute to TSA failure by creating a suboptimal bone-implant interface. They investigated the differences in depth penetration and heat generation of used community glenoid reamers in comparison to previous unused reamers.


They used a MTS Servohydraulic machine to test new and used community glenoid

reamers by applying the clinically relevant force of 54.7 N over a defined time. The depth of

penetration was measured via the MTS machine and the thermal profile was obtained via an

infrared camera. The used reamers were then set by the MTS machine to reach the same depth as the new reamers for all respective sizes while recording the force differential generated and capturing the thermal profile. 


At a constant force and time, the new reamers penetrated a greater depth (4.18 mm ± 2.17 mm) than the community used reamers (0.41 mm ± 0.22 mm), a difference of 3.80 mm ((95% CI, 2.23 mm to 5.31 mm), p < 0.001) without generating temperatures above 50°C


When programmed to reach the same average depth as the new reamers of equivalent sizes, the community reamers generated more heat on average (50.02 °C ± 2.88 °C), a difference of 5.98 °C ((95% CI, 3.40 to 8.53), p < 0.001). The used reamers on average also required 218.20 N more force than the new reamers (54.71 N ± 28.69 N) to reach the same depth, with the medium (303.47 N ± 96.71 N) and large (261.72 N ± 55.28 N) reamers specifically requiring the largest amount of force.


They concluded that the sharpness of glenoid reamers varies in the community. In order to reach the necessary depth for adequate fixation of implants, orthopedic surgeons may be required to exert a substantially larger force when using dulled reamers in comparison to sharp reamers. As a consequence, the heat generated could increase the risk of thermal osteonecrosis contributing to glenoid loosening.


Comment: These articles point to the ability of reaming to generate bone-killing levels of heat in the glenoid bone. This heat may interfere with the healing of bone in a ream and run procedure and with the stability of fixation in total shoulder arthroplasty.



Here are some videos that are of shoulder interest
Shoulder arthritis - what you need to know (see this link).
How to x-ray the shoulder (see this link).
The ream and run procedure (see this link).
The total shoulder arthroplasty (see this link).
The cuff tear arthropathy arthroplasty (see this link).
The reverse total shoulder arthroplasty (see this link).
The smooth and move procedure for irreparable rotator cuff tears (see this link).
Shoulder rehabilitation exercises (see this link).

Total shoulder arthroplasty: more severe anemia => more complications

Increased Severity of Anemia is Associated with Postoperative Complications following Primary Total Shoulder Arthroplasty


These authors sought to determine the influence of preoperative anemia severity on 30-day postoperative complications following primary TSA using the National Surgical Quality Improvement Program (NSQIP) database from 2012 to 2018. 

Patients undergoing TSA stratified into 3 cohorts: non-anemia (hematocrit >36% for women, > 39% for men), mild anemia (hematocrit 33% to 36% for women, 33% to 39% for men), and moderate to severe anemia (hematocrit < 33% for both women and men)


Of 13,921 total patients undergoing TSA, 11,330 patients (81.4%) did not have anemia, 1,934 (13.9%) had mild anemia, and 657 (4.7%) had moderate to severe anemia. 


Patients with mild anemia were more likely to have a postoperative blood transfusion (OR 4.7; p < 0.001), extended length of stay (OR 1.7; p = 0.002), and reoperation (OR 1.5; p =0.028). 


Patients with moderate to severe anemia were at increased risk of cardiac complications (OR 3.0; p = 0.012), pulmonary complications (OR 2.2; p = 0.015), postoperative blood transfusion (OR 23.8; p < 0.001), extended length of stay (OR 6.6; p < 0.001), reoperation (OR 2.2; p = 0.003), and death (OR 3.8; p = 0.034).


These findings are similar to those from another recent study.

 The Impact of Preoperative Anemia on Complications After Total Shoulder Arthroplasty


These authors investigated the relationship between varying levels of preoperative anemia and postoperative complications within 30 days of total shoulder arthroplasty (TSA) in 10,547 patients. 


The degree of anemia was categorized based on preoperative hematocrit levels: normal (>39% for men and >36% for women), mild anemia (29% to 39% for men and 29% to 36% for women), and severe anemia (<29% for both men and women).


1,923 patients were (18.2%) in the mild anemia cohort and 146 (1.4%) were in the severe anemia cohort. 


Mild anemia was a significant predictor of any complication (odds ratio [OR] 2.74, P < 0.001), stroke/cerebrovascular accident (OR 6.79, P = 0.007), postoperative anemia requiring transfusion (OR 6.58, P < 0.001), nonhome discharge (OR 1.79, P < 0.001), readmission (OR 1.63, P < 0.001), and return to the surgical room (OR 1.60, P = 0.017). 


Severe anemia was identified as a significant predictor of any complication (OR 4.31, P < 0.001), renal complication (OR 13.78, P < 0.001), postoperative anemia requiring transfusion (OR 5.62, P < 0.001), and nonhome discharge (OR 2.34, P < 0.001).


Comment: These authors found that 20% of patients having TSA were anemic! Preoperative anemia status was a notable risk factor for postoperative complications within 30 days of TSA. Even mildly decreased preoperative hematocrit levels (between 29% and 36% for women and between 29% and 39% for men) notably increased the risk of stroke/CVA, postoperative anemia requiring transfusion, nonhome discharge, hospital readmission, and return to the surgical room. In addition, severe anemia (hematocrit <29% in both men and women) was identified as a predictor of postoperative anemia requiring transfusion, nonhome discharge, and renal complications after TSA.


greater proportion of patients with mild anemia were functionally dependent, used steroids, had an ASA ≥3, and had a BMI <25. 


Anemia may result from nutrient deficiency, chronic proinflammatory states, chronic kidney disease, and bone marrow dysfunction. Deficiencies of vitamin B12, iron, and folate may account for one third of the etiologies of anemia. 


These studies did not evaluate the effectiveness of correcting patients' hematocrit preoperatively on postoperative complications after TSA. 



Here are some videos that are of shoulder interest
Shoulder arthritis - what you need to know (see this link).
How to x-ray the shoulder (see this link).
The ream and run procedure (see this link).
The total shoulder arthroplasty (see this link).
The cuff tear arthropathy arthroplasty (see this link).
The reverse total shoulder arthroplasty (see this link).
The smooth and move procedure for irreparable rotator cuff tears (see this link).
Shoulder rehabilitation exercises (see this link).

Is a plexus block of value for shoulder arthroplasty?

Liposomal bupivacaine interscalene nerve block in shoulder arthroplasty is not superior to plain bupivacaine: a double-blinded prospective randomized control trial 


These authors sought to evaluate whether liposomal bupivacaine would provide superior pain relief for shoulder replacement patients over bupivacaine alone. Patients received two anesthetics, a general anesthetic and a block with one of the two bupivacaine formulations.


They found no clinically relevant advantage to the use of liposomal bupivacaine over plain bupivacaine. Complications from the blocks were not reported.


Comment: There is no question that narcotic pain medications place patients at risk for nausea/vomiting, respiratory depression, constipation, falling, urinary retention, and confusion. 


While some authors use plexus blocks to minimize narcotics, as shown below, plexus blocks have potentially serious risks as well.


Our practice is to avoid the risks, time and cost of plexus blocks for shoulder arthroplasty. Instead, we employ preoperative education and a multimodal approach including Tylenol, Celebrex and Gabapentin. Assisted motion is started for all anatomic arthroplasties immediately after surgery in the recovery room.

With this "block-less" program our patients have minimal difficulty in starting their immediate postoperative range of motion exercises as is shown here for a 63 year old man on the morning after his ream and run arthroplasty immediately prior to his discharge.




Our reasons for avoiding interscalene blocks for shoulder arthroplasty include (1) desire for documentation of neurological status immediately after surgery, (2) wanting to avoid having a flail unprotected arm as we start immediate postoperative motion exercises, (3) eliminating the risk of block-related neurologic or pulmonary complications, (4) avoiding phrenic nerve paresis with the attendant respiratory compromise, (5) eliminating the inconvenience of a failed block, (6) reducing the cost (professional and materials) associated with two different anesthetics (block + general), (7) avoiding the problem of acute rebound pain in the middle of the first postoperative night, and (8) the reluctance of some patients to have a needle placed in their neck.



Here is a bit more discussion regarding the issues with blocks:

 Single-Shot Versus Continuous Interscalene Block for Postoperative Pain Control After Shoulder Arthroplasty: A Prospective Randomized Clinical Trial


In a randomized study, these authors compared continuous interscalene block (CIB) with single-shot interscalene block for postoperative control in 76 patients having shoulder arthroplasty.

Pain scores (P = 0.010) and opioid use (P = 0.003) on the first postoperative day were lower in the CIB group, but there was no difference in length of stay. Note that over half of the patients had a length of stay over one day.



Adverse events were more common in the CIB group; 10% of catheters pulled out prematurely. One patient required pacemaker implantation after syncopal episodes that may have been related to inadvertent intravascular injection.The authors point out that with plexus block anesthesia, the potential for serious complication remains and that centers with great experience in regional anesthesia have reported serious complications including pneumothorax and intravascular injection as well as transient and permanent postoperative loss of nerve function. 


They conclude that the benefits of CIB may not justify the complication rate and higher costs*.

*Note that the costs listed in this table do not include the professional fees for the anesthesiologist's time for performing either a single shot or a CIB.


Continuous versus single shot brachial plexus block and their relationship to discharge barriers and length of stay

These authors conducted a retrospective review of 697 patients undergoing upper extremity arthroplasty comparing the rate of complications and incidence of potential barriers to discharge and length of stay of patients receiving continuous vs. single-shot perineural brachial plexus block.

The complication rate was 12% (n=63) for the indwelling group and 17% (n=30) for the single-shot group.



The majority of complications were pulmonary, 72% attributable to oxygen desaturation. The indwelling catheter group had 1.61 times higher odds (95% confidence interval, 1.07-2.42; P = .023) of exhibiting any potential barrier to discharge and exhibited a longer length of stay (P = .002).

Our thoughts on interscalene block anesthetics can be viewed here:

Why not just do an interscalene nerve block anesthetic?

and here

The types and severity of complications associated with interscalene brachial plexus block anesthesia: local and national evidence.


Here are some videos that are of shoulder interest
Shoulder arthritis - what you need to know (see this link).
How to x-ray the shoulder (see this link).
The ream and run procedure (see this link).
The total shoulder arthroplasty (see this link).
The cuff tear arthropathy arthroplasty (see this link).
The reverse total shoulder arthroplasty (see this link).
The smooth and move procedure for irreparable rotator cuff tears (see this link).
Shoulder rehabilitation exercises (see this link).

Sunday, February 21, 2021

Total shoulder arthroplasty - are the patient outcomes improving with new technologies?

Assessing the Value to the Patient of New Technologies in Anatomic Total Shoulder Arthroplasty 


These authors point out that 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. The number of new technologies is increasing dramatically.


Some of the new technologies are 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 patientreported outcomes is unknown. 

They 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. 

Their 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. 

The figures below show the average preoperative to postoperative change in the different outcome measures for studies published over the last two decades. The linear trend line is shown. The two horizontal lines represent the lower and higher values for the minimal clinically important difference (MCID) reported for the outcome measure.





They concluded that additional research is required to document the clinical value of these new technologies to patients with glenohumeral arthritis. 

Here are some videos that are of shoulder interest
Shoulder arthritis - what you need to know (see this link).
How to x-ray the shoulder (see this link).
The ream and run procedure (see this link).
The total shoulder arthroplasty (see this link).
The cuff tear arthropathy arthroplasty (see this link).
The reverse total shoulder arthroplasty (see this link).
The smooth and move procedure for irreparable rotator cuff tears (see this link).
Shoulder rehabilitation exercises (see this link).

Monday, February 15, 2021

Reverse total shoulder with latissimus doors and treres major transfer: 35% complication rate

Mid- to long-term outcomes after reverse shoulder arthroplasty with latissimus dorsi and teres major transfer for irreparable posterosuperior rotator cuff tears

These authors point out that traditional RSA may be unable to restore active external rotation in the presence of massive posterosuperior cuff tears with non-functional infraspinatus and teres minor muscles.


They reviewed their experience with 17 patients having the Arrow reverse shoulder arthroplasty (RSA) combined with modified LEpiscopo procedure at long-term follow-up (5 to 12 years).


All patients (16) demonstrated a significant improvement in all clinical and functional parameters. VAS pain scores improved from 6 ± 2.6 to 1 ± 1; SSV improved from 35 ± 14 to 72 ± 10; active forward elevation increased from 66° ± 34 to 125°± 29; and active external rotation arm at the body increased from 11° ± 22 to 21° ±11 and in 90° of abduction from 10° ± 17 to 37° ± 24. The mean Constant score improved from 25 ± 11 to 59 ± 8. 


A total of six complications (35%) were identified in the study. Five cases were revised, and one was offered a revision surgery but refused any further surgical intervention. These cases consisted of five major complications including two infections, one case of inferior subluxation of the prosthesis, one traumatic dislocation with polyethylene disengagement, one superior migration of the baseplate, and one minor complication consisting of soft tissue irritation caused by a metaphyseal cerclage wire.




The effect of complications on the outcome is shown below.


















Comment: While this is a small series, the length of followup makes it of interest. While the complication rate was high, management of the complications yielded improvement over the preoperative condition. 


Here are some videos that are of shoulder interest
Shoulder arthritis - what you need to know (see this link).
How to x-ray the shoulder (see this link).
The ream and run procedure (see this link).
The total shoulder arthroplasty (see this link).
The cuff tear arthropathy arthroplasty (see this link).
The reverse total shoulder arthroplasty (see this link).
The smooth and move procedure for irreparable rotator cuff tears (see this link).
Shoulder rehabilitation exercises (see this link).