Total shoulder arthroplasty using a subscapularis-sparing approach: a radiographic analysis

Harms reporting in randomized controlled trials underpinning the American Academy of Orthopaedic Surgeons clinical practice guidelines for glenohumeral osteoarthritis

BACKGROUND

Glenohumeral osteoarthritis is one of the most common causes of shoulder pain. As such, the American Academy of Orthopaedic Surgeons (AAOS) has developed clinical practice guidelines (CPGs) to address the management of glenohumeral osteoarthritis. These CPG recommendations stem from the findings of randomized controlled trials (RCTs), which have been shown to influence clinical decision making and health policy. Therefore, it is essential that trial outcomes, including harms data (ie, adverse events), are adequately reported. We intend to evaluate the reporting quality of harms-related data in orthopedic literature specifically relating to AAOS CPG recommendations on the management of glenohumeral osteoarthritis.

METHODS

We adhered to the Preferred Reporting Items for Systematic Reviews (PRISMA) as well as guidance for reporting meta-research. The AAOS CPGs for glenohumeral osteoarthritis were obtained from orthoguidelines.org, and 2 authors independently screened the guidelines for the RCTs referenced. A total of 14 studies were identified. Data were extracted from the 14 included studies independently by the same 2 authors. Adherence to the Consolidated Standards of Reporting Trials (CONSORT) Extension for Harms Checklist was assessed using an 18-item scoring chart, with 1 point being awarded for meeting a checklist item and 0 points being awarded for not meeting a checklist item. Descriptive statistics, such as frequencies, percentages, and 95% confidence intervals were used to summarize RCT adherence to the CONSORT checklist.

RESULTS

The average score among the studies included was 7.36/18 items (39% adherence). No study adhered to all criteria, with the highest-performing study meeting 11 of 18 items (58%) and the lowest meeting 3 of 18 items (16%). A positive correlation between checklist score and year of publication was observed, with studies published more recently receiving a higher score on the CONSORT checklist (P < .05). Studies that disclosed funding information received a higher score than those that did not (P < .05), but there was no significant difference when the different funding sources were compared. Finally, double-blinded studies scored higher on the checklist than those with lower levels of blinding (single or no blinding, P < .05).

CONCLUSION

Adverse events are poorly reported amongst RCTs cited as supporting evidence for AAOS Management of Glenohumeral Osteoarthritis CPGs, evidenced by a CONSORT checklist compliance rate of only 41% in this study. We recommend the development of an updated checklist with information that makes it easier for authors to recognize, evaluate, and report on harms data. Additionally, we encourage authors to include information about adverse events or negative outcomes in the abstract.

Subscapular sparing approach for total shoulder arthroplasty: a systematic review and meta-analysis of comparative studies

Background

Total shoulder arthroplasty has been effective in treating primary glenohumeral arthritis surgically. However, the subscapularis (SSC) tendon must be released as part of the surgery's conventional approach, which could lead to postoperative problems and later tendon failure. Using a procedure that spares the tendon, Lafosse et al reported improved postoperative SSC performance. This meta-analysis will compare this approach to the standard one.

Methods

PubMed, Cochrane, and Google Scholar (pages 1-20) were searched till October 2022. The clinical outcomes consisted of the postoperative pain, adverse events, and range of motion.

Results

Only 3 studies were included in this meta-analysis. The subscapularis sparing approach tended to have better postoperative internal rotation (P = .06) and shoulder elevation (P = .1); however, the results were marginally statistically insignificant.

Conclusion

This is the first meta-analysis to compare the subscapularis sparing to the standard approach in total shoulder arthroplasty. Showing better postoperative range of motion (elevation and internal rotation), the SSC approach might be considered as a good substitute to the standard one. However, it is limited by the potentially limited exposure making it harder to use in muscular and obese patients. More randomized clinical trials are needed to reach more significant results and establish clearer indications of this approach.

Ultrasound assessment after a subscapularis-sparing approach to total shoulder arthroplasty

BACKGROUND

Although anatomic total shoulder arthroplasty (ATSA) has favorable outcomes, nearly all techniques involve subscapularis tendon release for shoulder joint access. Such takedown of the subscapularis may be associated with decreased function, instability, and pain. Subscapularis-sparing approaches have the theoretical benefits of improved function, decreased failure of the tendon reattachment site, and early range of motion and rehabilitation. The primary purpose of this study was to use ultrasound to assess the postoperative integrity of the subscapularis tendon and surrounding soft tissues after ATSA with a subscapularis-sparing technique through an extensile anterosuperior skin incision. Our hypothesis was that this subscapularis-sparing approach would have low rates of subscapularis disruption.

METHODS

A consecutive cohort of patients who underwent subscapularis-sparing ATSA between 2014 and 2017 were included. Ultrasound was used to evaluate the rotator cuff tendons and deltoid postoperatively, and these were classified as intact, disrupted, or unable to be adequately visualized. Clinical outcome scores, range of motion, and strength measurements were also collected at 1-3 years postoperatively.

RESULTS

Thirty-seven subscapularis tendons and 40 supraspinatus and infraspinatus muscles were adequately visualized and included for analysis. Of the subscapularis muscles, 32 (86%) were intact; 38 of the visualized supraspinatus muscles (95%) and 39 of the infraspinatus muscles (98%) were intact. No dehiscence or loss of integrity of the deltoid was noted. Clinical comparison between patients with disrupted subscapularis muscles and patients without such disruption demonstrated no difference in clinical outcome scores and postoperative range of motion but showed less strength in forward flexion, abduction, and external rotation.

CONCLUSIONS

The rate of subscapularis disruption using a subscapularis-sparing approach for ATSA was low (14%), but the potential for tendon disruption was not eradicated. Favorable clinical outcomes support this surgical approach as a potential technique for ATSA.

Implant Sizing and Positioning in Anatomical Total Shoulder Arthroplasty Using a Rotator Cuff-Sparing Postero-Inferior Approach

Background: The goal of this study was to compare the effectiveness of a rotator cuff-sparing postero-inferior (PI) approach with subdeltoidal access to the traditional subscapularis-takedown deltopectoral approach, in terms of implant sizing and positioning in anatomical total shoulder arthroplasty (aTSA). Methods: This study involved 18 human cadaveric shoulders with intact rotator cuffs and no evidence of head deforming osteoarthritis. An Eclipse stemless aTSA (Arthrex, Naples, FL, USA) was implanted in nine randomly selected specimens using a standard subscapularis-tenotomy deltopectoral approach, and in the other nine specimens using the cuff-sparing PI approach. Pre- and postoperative antero-posterior (AP) and axillary fluoroscopic radiographs were analyzed by two independent, blinded raters for the following parameters: (1) anatomic and prosthetic neck-shaft angle (NSA); (2) the shift between the anatomic and prosthetic center of rotation (COR); (3) anatomical size matching of the prosthetic humeral head; (4) the calculated Anatomic Reconstruction Score (ARS); (5) glenoid positioning; as well as (6) glenoid inclination and version. Results: While the COR was slightly but significantly positioned (p = 0.031) to be more medial in the PI approach group (3.7 ± 3.4%, range: −2.3% to 8.7%) than in the deltopectoral approach group (−0.2 ± 3.6%, range: −6.9% to 4.1%), on average, none of the remaining measured radiographic parameters significantly differed between both groups (PI approach group vs. deltopectoral group: NSA 130° vs. 127°, p = 0.57; COR supero-inferior, 2.6% vs. 1.0%, p = 0.35; COR antero-posterior, 0.9% vs. 1.7%, p = 0.57; head size supero-inferior, 97.3% vs. 98.5%, p = 0.15; head size antero-posterior, 101.1% vs. 100.6%, p = 0.54; ARS, 8.4 vs. 9.3, p = 0.13; glenoid positioning supero-inferior, 49.1% vs. 51.1%, p = 0.33; glenoid positioning antero-posterior, 49.3% vs. 50.4%, p = 0.23; glenoid inclination, 86° vs. 88°, p = 0.27; and glenoid retroversion, 91° vs. 89°, p = 0.27). Conclusions: A PI approach allows for sufficient exposure and orientation to perform rotator-cuff sparing aTSA with acceptable implant sizing and positioning in cadaveric specimens.

Subscapularis Repair Prior to Subscapularis Takedown in Anatomic Shoulder Arthroplasty: Improving Anatomic Restoration and Mechanics of the Subscapularis

Traditionally, total shoulder arthroplasty is performed using a deltopectoral approach through which the glenohumeral joint is accessed by mobilization of the subscapularis. Despite several variations on the subscapularis management techniques, postoperative complications, including subscapularis deficiency and lower functional outcomes, remain an area for improvement. The purpose of this Technical Note is to describe in detail our technique for management of the subscapularis in the setting of a stemless humeral implant through which the repair is planned and almost entirely performed at the beginning of the case, prior to the subscapularis peel. This technique aims to improve outcomes after total shoulder arthroplasty by 1) avoiding the anatomic implant with anchor drilling, 2) improving procedure efficiency, and 3) anatomically "repairing" the subscapularis prior to takedown by placing anchors exactly at the repair-tension site.

What Are Practical Surgical Anatomic Landmarks and Distances from Relevant Neurologic Landmarks in Cadavers for the Posterior Approach in Shoulder Arthroplasty?

BACKGROUND

Traditional total shoulder arthroplasty is performed through the deltopectoral approach and includes subscapularis release and repair. Subscapularis nonhealing or dysfunction may leave patients with persistent pain, impairment, and instability. Alternative approaches that spare the subscapularis include rotator interval and posterior shoulder approaches; however, to our knowledge, a cadaveric study describing pertinent surgical anatomy for a posterior shoulder approach regarding shoulder arthroplasty has not been performed.

QUESTIONS/PURPOSES

(1) What are the distances from important neurologic structures of the shoulder for arthroplasty through a posterior approach? (2) What surgical landmarks can help identify the internervous interval between the infraspinatus and teres minor?

METHODS

Twelve hemitorso cadaver specimens with intact rotator cuffs were dissected to study posterior shoulder anatomy regarding posterior shoulder arthroplasty. The median (range) age of the specimens was 79 years (55 to 92). Six of the 12 specimens were right-hand dominant, and 10 specimens were male. Cadaver height was a median 171 cm (155 to 191) and weight was a median of 68 kg (59 to 125). A posterior deltoid split and internervous approach between the infraspinatus and teres minor were used. A posterior T capsulotomy was performed. The distances to important neurologic structures were measured with an electronic caliper and provided in median (range) distances in millimeters. Although not as meaningful as distance ratios accounting for a specimen's body size, neurologic distances in millimeters are surgically practical and provide intraoperative usefulness. Surgical landmarks that can help identify the infraspinatus and teres minor plane were noted. Practical visual and tactile cues between the infraspinatus and teres minor were identified. Posterior rotator cuff tendon morphologies and widths were recorded.

RESULTS

The closest important neurologic structure was the axillary nerve, measuring a median (range) 17 mm (9 to 19) from the inferior glenoid rim while the infraspinatus branch of the suprascapular nerve measured 21 mm (15 to 36) from the posterior glenoid rim. The axillary nerve measured 84 mm (70 to 97) from the posterior tip of the acromion in the deltoid split. Three surgical landmarks were helpful for identifying the plane between the infraspinatus and teres minor in all 12 specimens: (1) identifying the triangular teres minor tendon insertion, (2) medial palpation identifying the low point between the prominent muscle bellies of the infraspinatus and teres minor, and (3) identifying the distinct and prominent teres minor tubercle, which is well localized and palpable.

CONCLUSION

A major benefit of the posterior approach for shoulder arthroplasty is subscapularis preservation. Multiple practical surgical cues are consistently present and can help identify the infraspinatus and teres minor interval. We did not find the presence of fat stripes to be helpful. The suprascapular nerve is in proximity to posterior surgical dissection and differs from the deltopectoral approach. This is an important distinction from an anterior approach and requires care with dissection. Future studies are necessary to assess iatrogenic risk to the posterior rotator cuff and external rotation strength. This may entail intraoperative nerve conduction studies of the posterior rotator cuff and clinical studies assessing external rotation strength.

CLINICAL RELEVANCE

Studying posterior shoulder anatomy is an initial first step to assessing the feasibility of the posterior approach for anatomic shoulder arthroplasty. Additional studies assessing the degree of glenohumeral exposure and possible iatrogenic posterior rotator cuff injury are necessary. Because of the proximity of neurologic structures, it is recommended that surgeons not perform this technique until sufficient evidence indicates that it is equivalent or superior to standard anterior approach total shoulder arthroplasty. After such evidence is available, proper training will be necessary to ensure safe use of the posterior shoulder approach.

Posterior approach shoulder arthroplasty: a cadaveric study assessing access

BACKGROUND

Posterior shoulder arthroplasty is an approach to shoulder replacement. The goal of this cadaveric study was to determine anatomic feasibility for posterior approach shoulder arthroplasty by evaluating access to the glenoid, humerus, and canal.

METHODS

Twelve fresh frozen shoulders (10 males; 2 females) (mean age, 76 [range, 55-92 years]; weight, 79 kg [range, 34-125 kg]) were used. Traditional exposure techniques and retractors were used to evaluate direct access. Exposure to the glenoid and humerus was evaluated using digital imaging software. Successful placement from stemmed arthroplasty was evaluated using digital radiographs and imaging software.

RESULTS

The posterior approach permitted direct access to 88.8% ± 8.1% of the glenoid. There was access to the center of the humeral head cut surface in 12 of 12 specimens. In 10 specimens, there was 100% access to the entire cut surface of the humerus and peripheral edges. The average access to the humerus was 95.3% ± 13.4%. Average angulation with stem placement was 0.73° of varus (range, 4.4° of varus to 3.5° of valgus). Regarding lateral plane angulation, there was an average of 0.33° of posterior angulation (range, 3.3° of posterior angulation to 2.5° of anterior angulation).

CONCLUSION

Access to the center of the glenoid and humerus was achieved in all cases. More research is needed to evaluate the clinical efficacy of posterior shoulder arthroplasty, including mid- and long-term outcome and safety studies.

The subscapularis-sparing windowed anterior technique for total shoulder arthroplasty

BACKGROUND

Traditionally, total shoulder arthroplasty (TSA) involves detaching the subscapularis tendon through either tenotomy or lesser tuberosity osteotomy. A subscapularis-sparing approach avoids detachment but may make re-creation of the anatomy more difficult because of limited exposure. The primary aim of this study was to evaluate the ability to re-create the proximal humeral geometry and assess for osteophyte removal with this technique. The secondary aim was to assess for complications or an inability to complete the procedure with this technique.

METHODS

We performed a retrospective review of a consecutive series of 47 patients (100% with osteoarthritis; 59% Walch type A and 41% Walch type B; 50% male and 50% female patients; and average body mass index, 28.21 ± 4.6) who underwent the subscapularis-sparing windowed anterior technique for TSA. The ability to reconstruct the proximal humeral geometry and remove the inferior osteophytes was assessed by 2 independent observers using the center-of-rotation difference (ΔCOR) between the native and prosthetic humeral heads. The ability to complete the procedure was recorded, and a chart review was performed to assess for complications.

RESULTS

The procedure was successfully completed in 44 of the 47 patients. Radiographic review demonstrated an average ΔCOR of 2.28 mm (range, 0.2-6.05 mm; intraclass correlation coefficient, 0.971), below the previously reported acceptable ΔCOR of 3 mm. The ΔCOR was >3 mm in 31.8% of patients (14 of 44; 8 Walch type A and 6 Walch type B; 9 male and 5 female patients). There was no difference in ΔCOR based on Walch type (P = .824). Male patients on average showed a higher ΔCOR (2.62 mm) than female patients (1.94 mm) (P = .099) and more commonly had a ΔCOR > 3 mm (P = .195). Body mass index was not significantly correlated with ΔCOR (r = 0.077, P = .619). For all cases in which the ΔCOR was >3 mm, the prosthetic humeral head was undersized. Osteophytes were successfully removed in 75% of cases (33 of 44) and had no effect on average ΔCOR (P = .468). No revisions or mechanical failures in the early postoperative period were identified in the treatment group of 44 patients (range, 3-15 months). In the group with unsuccessful treatment, there was 1 case of infection treated with 1-stage revision reverse TSA.

DISCUSSION

The subscapularis-sparing windowed anterior technique is an effective approach to TSA that allows for early unrestricted motion. Over 90% of cases can be completed using this technique. Radiographic analysis demonstrated that this approach can be used successfully without compromising anatomic reconstruction of the proximal humerus. Further study is necessary to identify patient factors that would favor a traditional deltopectoral approach and to assess the functional outcomes of this technique.

Subscapularis-sparing approaches in shoulder arthroplasty: A systematic review

Background

Novel approaches for anatomic and reverse total shoulder arthroplasty (aTSA and rTSA) that spare the subscapularis (SSC) have recently been described. Outcomes for the SSC-sparing approach were evaluated through this systematic review.

Methods

Medline, Embase, PubMed, and CENTRAL were searched.

Results

From 2051 citations, 8 studies were included (aTSA group, n = 241; rTSA group, n = 68). SSC-sparing aTSA and rTSA were associated with significant postoperative improvements in shoulder function and range of motion at 12- to 24-month follow-up.

Conclusion

The SSC-sparing approach may provide a safe alternative for up to two years post-surgery. Evidence for long-term use remains inconclusive.

The American Society of Shoulder and Elbow Therapists' consensus statement on rehabilitation for anatomic total shoulder arthroplasty

Anatomic total shoulder arthroplasty is the gold standard shoulder replacement procedure for patients with an intact rotator cuff and sufficient glenoid bone to accommodate prosthetic glenoid implant and offers reliable patient satisfaction, excellent implant longevity, and a low incidence of complications. Disparity exists in the literature regarding rehabilitation strategies following anatomic total shoulder arthroplasty. This article presents a consensus statement from experts in the field on rehabilitation following anatomic total shoulder arthroplasty. The goal of this consensus statement is to provide a current evidence-based foundation to inform the rehabilitation process after anatomic total shoulder arthroplasty. These guidelines apply to anatomic total shoulder arthroplasty (replacement of the humeral head and glenoid), hemiarthroplasty (replacing only the humeral head), and hemiarthroplasty with glenoid reaming or resurfacing. The consensus statement integrates an extensive literature review, as well as survey results of the practice patterns of members of the American Society of Shoulder and Elbow Therapists and the American Shoulder and Elbow Surgeons. Three stages of recovery are proposed, which initially protect and then gradually load soft tissue affected by the surgical procedure, such as the subscapularis, for optimal patient outcomes. The proposed guidelines should be used in collaboration with surgeon preferences and patient-specific factors.

Total Shoulder Arthroplasty Utilizing the Subscapularis-Sparing Approach

Traditionally, total shoulder arthroplasty is performed through the deltopectoral approach with violation of the subscapularis tendon. In order to reduce the incidence of postoperative subscapularis dysfunction, the subscapularis-sparing approach, performed entirely through the rotator interval, was developed. This technique allows earlier rehabilitation and may potentially prevent subsequent subscapularis insufficiency and clinical failures.

Shoulder replacement surgery for osteoarthritis and rotator cuff tear arthropathy

BACKGROUND

Shoulder replacement surgery is an established treatment for patients with end-stage glenohumeral osteoarthritis or rotator cuff tear arthropathy who have not improved with non-operative treatment. Different types of shoulder replacement are commonly used, but their relative benefits and risks compared versus one another and versus other treatments are uncertain. This expanded scope review is an update of a Cochrane Review first published in 2010.

OBJECTIVES

To determine the benefits and harms of shoulder replacement surgery in adults with osteoarthritis (OA) of the shoulder, including rotator cuff tear arthropathy (RCTA).

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials, MEDLINE, Embase, CINAHL, SportDiscus, and Web of Science up to January 2019. We also searched clinical trial registers, conference proceedings, and reference lists from previous systematic reviews and included studies.

SELECTION CRITERIA

We included randomised studies comparing any type of shoulder replacement surgery versus any other surgical or non-surgical treatment, no treatment, or placebo. We also included randomised studies comparing any type of shoulder replacement or technique versus another. Study participants were adults with osteoarthritis of the glenohumeral joint or rotator cuff tear arthropathy. We assessed the following major outcomes: pain, function, participant-rated global assessment of treatment success, quality of life, adverse events, serious adverse events, and risk of revision or re-operation or treatment failure.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed trial quality and extracted data. We collected trial data on benefits and harms.

MAIN RESULTS

We included 20 studies involving 1083 participants (1105 shoulders). We found five studies comparing one type of shoulder replacement surgery to another type of shoulder replacement surgery, including three studies comparing conventional stemmed total shoulder replacement (TSR) surgery to stemmed humeral hemiarthroplasty. The remaining 15 studies compared one type of shoulder replacement to the same type of replacement performed with a technical modification or a different prosthetic component. We found no studies comparing shoulder replacement surgery to any other type of surgical treatment or to any type of non-surgical treatment. We found no studies comparing reverse total shoulder replacement surgery to any other type of treatment or to any type of replacement. Trial size varied from 16 to 161 participants. Participant mean age ranged from 63 to 81 years. 47% of participants were male. Sixteen trials reported participants with a diagnosis of osteoarthritis and intact rotator cuff tendons. Four trials reported patients with osteoarthritis and a rotator cuff tear or rotator cuff tear arthropathy. All studies were at unclear or high risk of bias for at least two domains, and only one study was free from high risk of bias (included in the main comparison). The most common sources of bias were lack of blinding of participants and assessors, attrition, and major baseline imbalance. Three studies allowed a comparison of conventional stemmed TSR surgery versus stemmed humeral hemiarthroplasty in people with osteoarthritis. At two years, low-quality evidence from two trials (downgraded for bias and imprecision) suggested there may be a small but clinically uncertain improvement in pain and function. On a scale of 0 to 10 (0 is no pain), mean pain was 2.78 points after stemmed humeral hemiarthroplasty and 1.49 points lower (0.1 lower to 2.88 lower) after conventional stemmed TSR. On a scale of 0 to 100 (100 = normal function), the mean function score was 72.8 points after stemmed humeral hemiarthroplasty and 10.57 points higher (2.11 higher to 19.02 higher) after conventional stemmed TSR. There may be no difference in quality of life based on low-quality evidence, downgraded for risk of bias and imprecision. On a scale of 0 to 100 (100 = normal), mean mental quality of life was rated as 57.4 points after stemmed humeral hemiarthroplasty and 1.0 point higher (5.1 lower to 7.1 higher) after conventional stemmed TSR. We are uncertain whether there is any difference in the rate of adverse events or the rate of revision, re-operation, or treatment failure based on very low-quality evidence (downgraded three levels for risk of bias and serious imprecision). The rate of any adverse event following stemmed humeral hemiarthroplasty was 286 per 1000, and following conventional stemmed TSR 143 per 1000, for an absolute difference of 14% fewer events (25% fewer to 21% more). Adverse events included fractures, dislocations, infections, and rotator cuff failure. The rate of revision, re-operation, or treatment failure was 103 per 1000, and following conventional stemmed TSR 77 per 1000, for an absolute difference of 2.6% fewer events (8% fewer to 15% more). Participant-rated global assessment of treatment success was not reported.

AUTHORS' CONCLUSIONS

Although it is an established procedure, no high-quality randomised trials have been conducted to determine whether shoulder replacement might be more effective than other treatments for osteoarthritis or rotator cuff tear arthropathy of the shoulder. We remain uncertain about which type or technique of shoulder replacement surgery is most effective in different situations. When humeral hemiarthroplasty was compared to TSR surgery for osteoarthritis, low-quality evidence led to uncertainty about whether there is a clinically important benefit for patient-reported pain or function and suggested there may be little or no difference in quality of life. Evidence is insufficient to show whether TSR is associated with greater or less risk of harm than humeral hemiarthroplasty. Available randomised studies did not provide sufficient data to reliably inform conclusions about adverse events and harm. Although reverse TSR is now the most commonly performed type of shoulder replacement, we found no studies comparing reverse TSR to any other type of treatment.

Subscapularis sparing total shoulder arthroplasty through a superolateral approach: a radiographic study

BACKGROUND

Most anatomic total shoulder arthroplasty (ATSA) techniques release and reattach the subscapularis tendon. The risk of failed healing is a widely recognized complication. The purpose of this study was to radiographically compare a traditional deltopectoral (DP) approach and a superolateral subscapularis sparing (SSS) technique through the rotator interval.

METHODS

A single, independent, blinded, reviewer analyzed preoperative and postoperative radiographs of patients undergoing ATSA performed by a single surgeon. The reviewer assessed humeral head height, humeral head medial offset, humeral head diameter, head-neck angle, humeral head centering, and coracohumeral offset, and used the anatomic reconstruction index (ARI) to evaluate overall reconstruction quality.

RESULTS

There were 70 SSS and 20 DP patients included. When comparing preoperative with postoperative differences, we found that there was no difference between groups in humeral head height (P = .19), humeral head medial offset (P = .38), and coracohumeral offset (P = .07). The DP group had a mean humeral head diameter oversizing of 1.4 mm, whereas the superolateral group had an undersizing of 2.8 mm (P < .001). The head-neck angle difference of the SSS approach was 2° greater than that found with the DP group (P < .001). The humeral head centering in the DP group was 7% displaced vs. 12% with the SSS group (P = .001) relative to the glenoid size. The ARI was 7.35 for the DP group and 6.93 for the SSS group (P = .50).

DISCUSSION AND CONCLUSIONS

Radiographic comparison of these 2 ATSA techniques identified no statistical significant difference in 4 of 7 radiographic measurements and ARI. The SSS ATSA is a reasonable approach that yields similar radiographic measurements as a traditional DP total shoulder arthroplasty approach.

Shoulder arthroplasty using mini-stem humeral components and a lesser tuberosity osteotomy

PURPOSE

To determine whether lesser tuberosity osteotomy (LTO) and mini-stem humeral components (MSHCs) can be safely and effectively used together in total and hemi-shoulder arthroplasty (TSA/HHA).

METHODS

This is a retrospective review of consecutive patients who underwent anatomic TSA/HHA utilizing combined LTO/MSHC with minimum 2-year follow-up. Six-week and final radiographs, range of motion, pain scores, and selected outcome measures were assessed.

RESULTS

Seventy five shoulders with mean follow-up of 27.8 months (24-50 months) were analyzed. Sixty-seven (89.3%) shoulders had uneventful LTO healing. There were five (6.67%) LTO failures, one (1.33%) fibrous union, and two (2.67%) osteotomies that had displaced > 4 mm at 6 weeks; four of the five failures required open repair, including one converted to reverse TSA. The other failure, the fibrous union, and the two displaced osteotomies were without clinical deficits and elected for non-operative management. One patient required intraoperative conversion to a long stem due to concern that metaphyseal bone integrity was compromised, in part, by the LTO. Four (5.33%) stems subsided, with one of them also being frankly loose and requiring revision, while the other three were asymptomatic, not requiring treatment. No other stems were judged to be loose. Mean ASES, SANE, VAS, forward flexion, external rotation, and internal rotation all improved significantly (p < 0.001 for all).

CONCLUSIONS

LTO/MSHC use is appropriate for TSA/HHA, achieving pain relief and functional improvement. Component loosening appears uncommon at early follow-up. Long-stem components should be available in case the metaphyseal bone is compromised. When performed properly, LTO/MSHC use is a safe and effective surgical strategy.

Comparison of Subscapularis Management and Repair Techniques

Management of the subscapularis tendon is a crucial step during the approach for total shoulder arthroplasty. The method of mobilizing the tendon and the technique used to repair it determine the initial integrity of the subscapularis and impact its capacity to heal. Currently, there exist 3 well-described and well-studied approaches to managing and repairing the subscapularis: subscapularis tenotomy, subscapularis peel, and lesser tuberosity osteotomy. More recently, a subscapularis-sparing approach has been proposed as an option. There is debate in the literature regarding which technique provides optimal strength and stability for subscapularis repair following shoulder arthroplasty. In this symposium, we provide an overview of each of the techniques and review the biomechanical studies comparing them.

Subscapularis-Sparing Total Shoulder Arthroplasty: A Prospective, Double-Blinded, Randomized Clinical Trial

Although total shoulder arthroplasty (TSA) is generally associated with good to excellent outcomes in most patients, the integrity and function of the subscapularis tendon (SSC) is of paramount importance because SSC rupture after TSA can lead to inferior outcomes. Therefore, the efficacy of a SSC-sparing TSA procedure was evaluated through a prospective, double-blinded, randomized study. Patients with end-stage osteoarthritis of the shoulder were randomized into 2 groups. Group 1 patients were treated with TSA in which the prosthesis was inserted entirely through the rotator interval without violating the SSC tendon (SPARING). Group 2 patients were treated with TSA using the SSC tenotomy approach (STANDARD). Both the patients and the evaluators remained blinded to the surgical approach throughout the study. Outcome data collected included the visual analog scale score for pain and the American Shoulder and Elbow Surgeons outcome score. Complete 2-year outcome data were collected from 32 SPARING and 38 STANDARD patients at a mean follow-up of 31.1 and 33.4 months, respectively. The American Shoulder and Elbow Surgeons and visual analog scale scores improved significantly for both groups. Differences between groups did not reach statistical significance. Complication profiles were similar for the 2 groups, with 3 patients in the SPARING group and 2 patients in the STANDARD group requiring revision surgery during the study. At short-term follow-up, the outcome of TSA using the SSC-sparing surgical approach was similar to the outcome of TSA using the standard approach. Studies with longer follow-up are required to document the potential benefits of this surgical technique. [Orthopedics. 2019; 42(1):e61-e67.].

Subscapularis Insufficiency: What’s All the Fuss About?

There has been increase attention to the surgical treatment of the subscapularis (SSC) tendon with risk of postoperative dysfunction and early failures following shoulder arthroplasty. Studies investigating the clinical results after shoulder arthroplasty indicate that SSC tendon detachment or incision techniques and rehabilitation concepts may impair SSC recovery and consequently the postoperative function. In response to these results, technical modifications have been proposed and evaluated anatomically, biomechanically, and clinically. The aim of this article is to give an overview of current SSC take-down approaches, subsequent repair techniques, and postoperative rehabilitation protocols as well as to present the diagnostic algorithm and clinical impacts of the increasingly acknowledged condition of SSC insufficiency following shoulder arthroplasty procedures.

Optimal management of glenohumeral osteoarthritis

Glenohumeral osteoarthritis (OA) is defined as progressive loss of articular cartilage, resulting in bony erosion, pain, and decreased function. This article provides a gross overview of this disease, along with peer-reviewed research by experts in the field. The pathology, diagnosis, and classification of this condition have been well described. Treatment begins with non-operative measures, including oral and topical anti-inflammatory agents, physical therapy, and intra- articular injections of either a corticosteroid or a viscosupplementation agent. Operative treatment is based on the age and function of the affected patient, and treatment of young individuals with glenohumeral OA remains controversial. Various methods of surgical treatment, ranging from arthroscopy to resurfacing, are being evaluated. The roles of hemiarthroplasty, total shoulder arthroplasty, and reverse shoulder arthroplasty are similarly reviewed with supporting data.

Subscapularis-On Approach in Reverse Shoulder Arthroplasty

Using a subscapularis- and deltoid-preserving anterior approach is an option for patients undergoing reverse shoulder arthroplasty. Outcomes are better at short term than compared with the standard deltopectoral approach. Maintaining the integrity of the subscapularis tendon and preserving the deltoid muscle minimizes the need for postoperative immobilization and rehabilitation, allowing the patient to achieve active shoulder range of motion more rapidly, without increasing the incidence of shoulder dislocation. Overall length of hospital stay and duration of postoperative physical therapy are minimized, leading to significant economic gain. Future studies with longer follow-up are required to document the potential long-term benefits of this surgical technique.

Level of Evidence of the study: Review, Level IV

Biomechanical characteristics of subscapularis-sparing approach for anatomic total shoulder arthroplasty

BACKGROUND

A technique for retaining the superior 50% of the subscapularis insertion for anatomic total shoulder arthroplasty has been described. This cadaveric study biomechanically evaluates this subscapularis-sparing approach and compares it with a complete subscapularis release and repair technique to determine whether there is a higher load to failure.

MATERIALS AND METHODS

Twelve matched pairs of human cadaveric arms were distributed into 3 test groups. Group 1 consisted of specimens with and without a 100% subscapularis release. Group 2 consisted of specimens with and without an inferior 50% subscapularis release. Group 3 consisted of specimens with either an inferior 50% or 100% release of the subscapularis footprint and repair. All tendon repairs were performed using bone tunnels and sutures. Specimens were biomechanically tested using non-destructive cyclic and tensile failure-inducing loads.

RESULTS

In matched pairs, the following comparative results were obtained: native intact subscapularis specimens exhibited a load to failure of 1341.20 ± 380.10 N compared with 380.10 ± 138.79 N in the 100% release specimens (P = .029), native intact subscapularis specimens exhibited a load to failure of 1209.74 ± 342.18 N compared with 744.33 ± 211.77 N in the 50% release specimens (P = .057), and 50% release and repair specimens exhibited a load to failure of 704.62 ± 165.53 N compared with 305.52 ± 91.39 N in the 100% release and repair group (P = .029).

CONCLUSION

Preservation of the superior 50% of the subscapularis demonstrates a higher load to failure compared with complete subscapularis release and repair using bone tunnels.

Anatomic Shoulder Arthroplasty: Technical Considerations

Osteoarthritis of the shoulder is a common condition in the aging population, and it can have profound effects on patients’ quality of life. The anatomic total shoulder arthroplasty is a well-described treatment modality resulting generally excellent outcomes. The objective of this review is to discuss the technical aspects of primary anatomic total shoulder arthroplasty, and to provide a framework to follow to achieve a successful surgical result. The topics covered include preoperative planning, surgical considerations, and approaches, humeral preparation, glenoid bone loss and the emerging concept of using the reverse total shoulder arthroplasty for the type B2 glenoid.

Shoulder Arthroplasty Imaging: What's New

Background

Shoulder arthroplasty, in its different forms (hemiarthroplasty, total shoulder arthroplasty and reverse total shoulder arthroplasty) has transformed the clinical outcomes of shoulder disorders. Improvement of general clinical outcome is the result of stronger adequacy of the treatment to the diagnosis, enhanced surgical techniques, specific implanted materials, and more accurate follow up. Imaging is an important tool in each step of these processes.

Method

This article is a review article declining recent imaging processes for shoulder arthroplasty.

Results

Shoulder imaging is important for shoulder arthroplasty pre-operative planning but also for post-operative monitoring of the prosthesis and this article has a focus on the validity of plain radiographs for detecting radiolucent line and on new Computed Tomography scan method established to eliminate the prosthesis metallic artefacts that obscure the component fixation visualisation.

Conclusion

Number of shoulder arthroplasties implanted have grown up rapidly for the past decade, leading to an increase in the number of complications. In parallel, new imaging system have been established to monitor these complications, especially component loosening.

How should I fixate the subscapularis in total shoulder arthroplasty? A systematic review of pertinent subscapularis repair biomechanics

BACKGROUND

The present study aimed to review the biomechanical outcomes of subscapularis repair techniques during total shoulder arthroplasty (TSA) to assist in clinical decision making.

METHODS

A systematic review of multiple databases was performed by searching PubMed, Scopus, Cochrane Library, Google Scholar, and all databases within EBSCOhost to find biomechanical studies of subscapularis repair techniques in cadaveric models of TSA.

RESULTS

Nine studies met the inclusion criteria. In the majority of studies, lesser tuberosity osteotomy (LTO) techniques had greater load to failure and less cyclic displacement compared to subscapularis tenotomy or peel methods. LTO repairs with sutures wrapped around the humeral stem demonstrated superior biomechanical outcomes compared to techniques using only a tension band. In terms of load to failure, the strongest repair of any study was a dual-row fleck LTO using four sutures wrapped around the stem.

CONCLUSIONS

Several cadaveric studies have shown superior biomechanical outcomes with LTO techniques compared to tenotomy. In the majority of studies, the strongest subscapularis repair technique in terms of biomechanical outcomes is a compression LTO. Using three or more sutures wrapped around the implant and the addition of a tension suture may increase the biomechanical strength of the LTO repair.

Proximal ingrowth coating decreases risk of loosening following uncemented shoulder arthroplasty using mini-stem humeral components and lesser tuberosity osteotomy

BACKGROUND

Mini-stem humeral component (MSHC) use during total shoulder arthroplasty (TSA) provides bone preservation and ease of revision. MSHCs rely solely on proximal metaphyseal fixation; some early reports have demonstrated an unacceptably high rate of early loosening. To our knowledge, no study analyzing the effect of proximal porous coating on MSHCs has been performed.

METHODS

We performed a retrospective review of consecutive patients who underwent anatomic TSA using coated or uncoated MSHCs with minimum 2-year follow-up. Postoperative radiographs were assessed for risk of or frank stem loosening, subsidence, and presence of radiolucencies. Range of motion, outcome scores (visual analog scale pain, American Shoulder and Elbow Surgeons, and Single Assessment Numeric Evaluation), and any complications were noted.

RESULTS

We analyzed 68 shoulders with a mean follow-up of 27.3 months (range, 24-50 months). Of these, 34 had proximal coating and 34 were uncoated. In the coated group, no stems loosened, 1 (2.9%) subsided, and 7 (20.6%) developed radiolucencies. In the uncoated group, 1 stem (2.9%) became aseptically loose (requiring revision after 26 months), 7 (20.6%) were judged at risk of loosening (2 because of subsidence), and 15 (44.1%) developed radiolucencies. There was also an increased risk of proximal medial humeral radiolucencies among uncoated MSHCs. There were no significant differences in final range of motion or outcome scores.

CONCLUSION

MSHC use is appropriate for TSA, achieving desired pain relief and functional improvement. Overall, component loosening appears uncommon at early follow-up; however, uncoated stems appear to be at greater risk of loosening and developing radiolucencies. Selecting an MSHC with proximal porous coating may decrease the risk of implant-related complications.

Lift-off Test Results After Lesser Tuberosity Osteotomy Versus Subscapularis Peel in Primary Total Shoulder Arthroplasty

BACKGROUND

The ideal method for management of the subscapularis tendon during anatomic total shoulder arthroplasty (TSA) remains controversial.

METHODS

In a retrospective cohort study, primary anatomic TSA procedures performed with either a subscapularis peel or a lesser tuberosity osteotomy from 2002 to 2010 were reviewed at a minimum 1-year follow-up. The primary outcome measure was the performance of a normal lift-off test postoperatively. Multivariate logistic regression analysis was performed to determine if other covariates besides surgical technique correlated with an abnormal lift-off test result.

RESULTS

Ninety TSA procedures were evaluated. Forty-six procedures were performed with subscapularis peel, and 44 were performed with lesser tuberosity osteotomy. Mean follow-up was 4 years. In the subscapularis peel group, 32 of 46 shoulders (69.6%) had a normal lift-off test, compared with 40 of 44 shoulders (90.9%) in the lesser tuberosity osteotomy group (P = 0.01). The results of multivariate logistic regression suggested that lesser tuberosity osteotomy was associated with a normal postoperative lift-off test 4.5 times more often than was subscapularis peel.

CONCLUSIONS

Our study suggests that the use of lesser tuberosity osteotomy as the surgical approach for anatomic TSA is a reliable option that provides the patient with a better chance of maintaining subscapularis function postoperatively than the subscapularis peel does.

LEVEL OF EVIDENCE

Level III retrospective cohort study.

Management of the subscapularis tendon during total shoulder arthroplasty

Use of total shoulder arthroplasty has significantly increased during the past decade. For anatomic total shoulder arthroplasty, controversy exists regarding the best technique for detachment and repair of the subscapularis tendon. Options include tendon tenotomy, peel, lesser tuberosity osteotomy, and even subscapularis-sparing techniques. Inadequate healing of the subscapularis tendon can lead to postoperative pain, weakness, and instability. This review discusses the subscapularis pathoanatomy, different techniques for releasing and repairing the tendon, and reports biomechanical and clinical outcomes for each technique after total shoulder arthroplasty.

Rotator cuff-sparing approaches for glenohumeral joint access: an anatomic feasibility study

BACKGROUND

The deltopectoral approach for total shoulder arthroplasty can result in subscapularis dysfunction. In addition, glenoid wear is more prevalent posteriorly, a region difficult to access with this approach. We propose a posterior approach for access in total shoulder arthroplasty that uses the internervous interval between the infraspinatus and teres minor. This study compares this internervous posterior approach with other rotator cuff-sparing techniques, namely, the subscapularis-splitting and rotator interval approaches.

METHODS

The 3 approaches were performed on 12 fresh frozen cadavers. The degree of circumferential access to the glenohumeral joint, the force exerted on the rotator cuff, the proximity of neurovascular structures, and the depth of the incisions were measured, and digital photographs of the approaches in different arm positions were analyzed.

RESULTS

The posterior approach permits direct linear access to 60% of the humeral and 59% of the glenoid joint circumference compared with 39% and 42% for the subscapularis-splitting approach and 37% and 28% for the rotator interval approach. The mean force of retraction on the rotator cuff was 2.76 (standard deviation [SD], 1.10) N with the posterior approach, 2.72 (SD, 1.22) N with the rotator interval, and 4.75 (SD, 2.56) N with the subscapularis-splitting approach. From the digital photographs and depth measurements, the estimated volumetric access available for instrumentation during surgery was comparable for the 3 approaches.

CONCLUSION

The internervous posterior approach provides greater access to the shoulder joint while minimizing damage to the rotator cuff.

Subscapularis and deltoid preserving anterior approach for reverse shoulder arthroplasty

HYPOTHESIS

We hypothesize that performing a RSA using an anterior approach without cutting the subscapularis tendon and the deltoid muscle could provide patients with superior short-term clinical outcomes and immediate active range of motion (ROM) without immobilization.

METHODS

Between August 2013 and June 2015, all patients who had a primary RSA were considered potentially eligible for inclusion in this prospective study.

RESULTS

No immediate intra- or postoperative complications were noted. A statistically significant improvement of VAS (from 6.7 to 1; P<.001), SANE (from 34 to 80; P<.001), and elevation (from 103° to 128°; P=.02) was observed. In some cases, patients who had pseudoparalysis preoperative were able to achieve full anterior elevation few days after the operation.

DISCUSSION

Using a subscapularis and deltoid preserving anterior approach is an option for patients requiring RSA. Leaving this tendon intact and preserving the deltoid minimize the need for immediate postoperative immobilization and allow for faster recovery of shoulder ROM, without risking the concern of humeral anterior dislocation. Overall duration of hospital stay as well as length of postoperative physical therapy may be minimized, with substantial long-term economic gain. Longer follow-up and comparison with standard approaches is necessary in the future.

LEVEL OF EVIDENCE OF THE STUDY

Level IV, case series with no comparative group.