Functional outcome after shoulder arthroplasty for primary osteoarthritis: a multicenter study

Three-Year Follow-up of Conservative Treatments of Shoulder Osteoarthritis in Older Patients

Little is known about the mid-term results of nonsurgical treatment for shoulder osteoarthritis (OA), especially in a Chinese population. This study sought to determine the efficacy of nonsurgical management in older patients with shoulder OA. A total of 129 conservatively treated unilateral shoulder OA patients who were older than 65 years were evaluated prospectively at the initial office visit and then subsequently at 3, 6, 12, 18, 24, and 36 months later. During the 36-month follow-up period, all patients could receive conventional therapy, such as nonsteroidal anti-inflammatory medication, corticosteroid injection, sodium hyaluronate, and education, at the discretion of treating physicians. Some patients received physiotherapy, rehabilitation training, and a shoulder strap to improve the range of motion and muscular strength training from a physical therapist. Parameters measured included comparative effectiveness of each therapeutic method, visual analog scale (VAS), Simple Shoulder Test (SST), and Short Form (36) Health Survey (SF-36) scores. At 3-year follow-up, most patients had a significant increase from their pretreatment values in pain, self-assessed shoulder function, mental health, and 5 of 8 SF-36 domains. The study showed a decline in SST and VAS at 6 and 12 months after an initial ascent at 3 months, and then it was rescued and continued at 3-year follow-up. Combined therapy could improve symptoms significantly. This study suggests that a conservative approach may be more appropriate and can produce satisfactory mid-term outcomes in selected cases. The findings of this study suggest that conservative treatments should be extended for longer than 12 months before the decision regarding shoulder arthroplasty is made. [Orthopedics. 2016; 39(4):e634-e641.].

Early Debris Formation with a Porous Tantalum Glenoid Component: Radiographic Analysis with 2-Year Minimum Follow-up

BACKGROUND

Porous tantalum has been used effectively in hip, knee, and reverse shoulder arthroplasty implants. However, a first-generation porous tantalum glenoid component for use in anatomic shoulder arthroplasty previously demonstrated failure, with failure usually preceded by the appearance of intra-articular metallic debris. After redesign, the component was reintroduced in 2009. The purpose of the current study was to evaluate the radiographic and clinical outcomes of the redesigned glenoid component.

METHODS

Sixty-eight patients undergoing total shoulder arthroplasty received a Trabecular Metal porous tantalum glenoid component (73 components; 5 patients underwent staged bilateral procedures). No polymethylmethacrylate cement was used (off-label usage in the U.S.). A grading system to assess metallic debris formation was developed using radiographs of the previous generation of porous tantalum glenoid components that failed. Radiographs from the current series were independently reviewed by 2 shoulder arthroplasty specialists, and their results were compared. Glenoid components were evaluated for signs of bone ingrowth and metallic debris formation.

RESULTS

Sixty-six (90%) of the 73 components were evaluated at a minimum of 2 years of follow-up (mean radiographic follow-up of 50.8 months; range, 24 to 68 months). Of these, 92.4% demonstrated minimal or no glenoid radiolucency. Overall, the prevalence of metallic tantalum debris formation was 44% (29 of 66). Sequential radiograph review demonstrated that the incidence of metallic debris formation increased for each year of follow-up, with radiographs from 2, 3, 4, and ≥5 years of follow-up demonstrating a metallic debris incidence of 23%, 36%, 49%, and 52%, respectively. Additionally, the severity of metallic debris formation increased with follow-up duration. There was no component dissociation or revision due to implant breakage in this series.

CONCLUSIONS

The porous tantalum glenoid component studied had excellent short-term component fixation. However, the development of metallic debris, increasing in both overall incidence and degree of severity over time, raises concern for potential failure of this glenoid component. Longer follow-up is required.

LEVEL OF EVIDENCE

Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Predictors for satisfaction after anatomic total shoulder arthroplasty for idiopathic glenohumeral osteoarthritis

INTRODUCTION

The use of total shoulder arthroplasty (TSA) to treat primary glenohumeral osteoarthritis (GHOA) is increasing. Factors influencing patient satisfaction after surgery have not been well documented. The aim of this study was to determine demographic, radiologic, and surgical, factors predictive for satisfaction after TSA for GHOA.

MATERIALS AND METHODS

Between 2005 and 2012, 95 shoulders undergoing TSA for GHOA by a single surgeon were eligible for inclusion in the study. Age, gender, previous surgeries, American Society of Anesthesiologists (ASA) score, and Walch glenoid morphology were analyzed as satisfaction predictors. Patients with Walch glenoid type C were excluded.

RESULTS

Data on 80/92(87 %) shoulders were available at a mean of 3 years (range 2-9). Three complications (3 %) and 2 failures (2 %) occurred. The outcome scores collected significantly improved from preoperative values (p < 0.05). Median patient satisfaction was 10/10. Gender, age, previous surgery, ASA score, and Walch morphology were not associated with patient satisfaction.

CONCLUSIONS

TSA provided excellent results for patients with idiopathic GHOA with low complication and failure rates. Outcomes after TSA for type B glenoid morphology with posterior subluxation were similar to outcomes after TSA for centered type A morphology. Overall patient satisfaction was high and was not influenced by the demographic, anatomic, and surgical variables investigated.

LEVEL OF EVIDENCE

III, Therapeutic study, Retrospective Cohort Study.

Accuracy of patient-specific instrumentation in anatomic and reverse total shoulder arthroplasty

PURPOSE

Glenoid component malposition is associated with poor function and early failure of both anatomic and reverse total shoulder arthroplasty. Glenoid positioning is challenging particularly in the setting of bone loss or deformity. Recently, the use of computer assistance has been shown to reduce implantation error. The aim of this study is to evaluate the accuracy of patient-specific instrumentation in cases of anatomic and reverse shoulder replacement in vivo.

METHODS

Twenty patients underwent total shoulder arthroplasty using a computed tomography (CT)-based patient-specific instrumentation (PSI) system, ten anatomic and ten reverse. Preoperative three-dimensional digital templating of glenoid component position was undertaken and surgery then performed using a custom-made guide. Postoperative CT scans were used to compare final implanted component position to the preoperatively planned position in the same patient.

RESULTS

Final component position and orientation closely reflected the preoperatively templated position. Mean deviation in the glenoid version from planned was 1.8° ±1.9° (range, 0.1°-7.3°). Mean deviation in inclination was 1.3° ±1.0° (range, 0.2°-4.5°). Mean deviation in position on the glenoid face was 0.5 ± 0.3 mm (range, 0.0-1.3 mm) in the anteroposterior plane and 0.8 ± 0.5 mm (range, 0.0-1.9 mm) in the superoinferior plane. Actual achieved version was within 7° of neutral in all cases except for one where it was deliberately planned to be outside of this range.

CONCLUSION

PSI in both anatomic and reverse shoulder arthroplasty is highly accurate in guiding glenoid component implantation in vivo. The system can reliably correct bony deformity.

Rotator cuff tears after total shoulder arthroplasty in primary osteoarthritis: A systematic review

Rotator cuff tears have been reported to be uncommon following total shoulder arthroplasty (TSA). Postoperative rotator cuff tears can lead to pain, proximal humeral migration, and glenoid component loosening. The purpose of this paper was to evaluate the incidence of post-TSA rotator cuff tears or dysfunction in osteoarthritic patients. A systematic review of multiple databases was performed using preferred reporting items for systematic reviews and meta-analyses guidelines. Levels I-IV evidence clinical studies of patients with primary osteoarthritis with a minimum 2-year follow-up were included. Fifteen studies with 1259 patients (1338 shoulders) were selected. Student's t-tests were used with a significant alpha value of 0.05. All patients demonstrated significant improvements in motion and validated clinical outcome scores (P < 0.001). Radiographic humeral head migration was the most commonly reported data point for extrapolation of rotator cuff integrity. After 6.6 ± 3.1 years, 29.9 ± 20.7% of shoulders demonstrated superior humeral head migration and 17.9 ± 14.3% migrated a distance more than 25% of the head. This was associated with an 11.3 ± 7.9% incidence of postoperative superior cuff tears. The incidence of radiographic anterior humeral head migration was 11.9 ± 15.9%, corresponding to a 3.0 ± 13.6% rate of subscapularis tears. We found an overall 1.2 ± 4.5% rate of reoperation for cuff injury. Nearly all studies reported indirect markers of rotator cuff dysfunction, such as radiographic humeral head migration and clinical exam findings. This systematic review suggests that rotator cuff dysfunction following TSA may be more common than previously reported. IV, systematic review of Levels I-IV studies.

Surgical treatments for osteoarthritis

There are two main surgical treatments for osteoarthritis: conservative treatments, where the damaged cartilage is left in place, and radical treatments, where the cartilage is replaced by an artificial endoprosthesis; this latter procedure is termed joint arthroplasty. These treatments are only offered to symptomatic patients. Arthrodesis is yet another surgical intervention in cases of osteoarthritis. It will sacrifice the joint's articular function and is performed on small osteoarthritic joints, such as wrists and ankles, for instance. Osteoarthritis symptoms are usually the consequence of an imbalance between the load applied to a joint and the surface available to support that load. Therefore, conservative treatments will either tend to decrease the load exerted on the joint, such as in a tibial valgus osteotomy for instance, or to improve the articular surface supporting that load. Sometimes, both can be provided at the same time; the peri-acetabular osteotomy for hip dysplasia is an example of such a procedure. Conservative treatments are usually offered to young patients in order to delay, if not avoid, the need for a joint prosthesis. They are usually performed before osteoarthritis appears or at an early stage. Joint arthroplasties have overwhelmingly excellent functional results and today's research is directed towards providing rapid recovery, very long-term stability, and the assurance of a good functionality in extreme conditions. However, complications with joint arthroplasties can be serious with little, if any, reasonable salvage solution. Therefore, these procedures are offered to patients who have failed adequate medical treatment measures.

Histological evaluation of two designs of shoulder surface replacement implants

AIMS

To assess the extent of osteointegration in two designs of shoulder resurfacing implants. Bony integration to the Copeland cylindrical central stem design and the Epoca RH conical-crown design were compared.

PATIENTS AND METHODS

Implants retrieved from six patients in each group were pair-matched. Mean time to revision surgery of Copeland implants was 37 months (standard deviation (sd) 23; 14 to 72) and Epoca RH 38 months (sd 28; 12 to 84). The mean age of patients investigated was 66 years (sd 4; 59 to 71) and 58 years (sd 17; 31 to 73) in the Copeland and Epoca RH groups respectively. None of these implants were revised for loosening.

RESULTS

Increased osteointegration was measured under the cup in the Copeland implant group with limited bone seen in direct contact with the central stem. Bone adjacent to the Epoca RH implants was more uniform.

CONCLUSION

This difference in the distribution of bone-implant contact and bone formation was attributed to the Epoca implant's conical crown, which is positioned in more dense peripheral bone. The use of a central stem may not be necessary provided there is adequate peripheral fixation within good quality humeral bone.

TAKE HOME MESSAGE

Poor osteointegration of cementless surface replacement shoulder prosthesis may be improved by implant design.

Total shoulder arthroplasty with an augmented component for anterior glenoid bone deficiency

BACKGROUND

Glenoid bone loss is a challenging problem when performing total shoulder arthroplasty (TSA). Posterior glenoid bone deficiency is more common than anterior deficiency, and so the literature on methods to treat anterior glenoid deficiency in the setting of TSA is not common. The purpose of this case series was to describe preoperative factors, surgical technique, and clinical outcomes in select patients who underwent placement of an anteriorly augmented glenoid component during TSA.

METHODS

This was a retrospective case series of 5 patients who underwent TSA with an anteriorly augmented component. The medical records were reviewed, including preoperative demographics, clinical examination, radiographs, Penn Shoulder Score and American Shoulder and Elbow Surgeons score.

RESULTS

Preoperative diagnoses were anterior glenoid erosion in 2 patients, and 1 patient each with malunited glenoid fracture, nonunited glenoid fracture, and post-traumatic arthritis. The mean age at the time of surgery was 67.4 years (range, 53-75 years). No patient demonstrated radiographic or clinical signs of glenoid component loosening at final follow-up. Postoperative Penn Shoulder Scores averaged 84.4 points (range, 58-100 points), and postoperative American Shoulder and Elbow Surgeons scores averaged 88.0 points (range, 68-100 points). Average postoperative active forward elevation was 140° (range, 80°-170°), and active external rotation was 29° (range 10°-45°). There were no dislocations or revision surgeries at an average of 33.2 months (range, 21.9-43.2 months) after surgery.

CONCLUSION

In the short term, glenohumeral arthrosis in the setting of anterior glenoid deficiency can be treated with an anteriorly augmented glenoid component. Further follow-up and a larger series of patients are necessary to determine the long-term outcomes and complications associated with this technique.

The arthritic glenoid: anatomy and arthroplasty designs

The number of shoulder arthroplasty procedures has increased dramatically in recent years, with the primary indication being osteoarthritis (OA). Thus, morphology and subchondral bone changes associated with OA may be important factors to consider when choosing a replacement component. For surgical treatment, many implant options exist and survivability is often dependent on patient age, activity level, and progression of OA. In the placement of these replacement components, patient-specific guides now exist to improve component positioning, with the goal to improve long-term survivability by ensuring that intra-operative placement meets component design.

Porous metals and alternate bearing surfaces in shoulder arthroplasty

Total shoulder arthroplasty (TSA) provides an effective solution for the treatment of glenohumeral arthritis. However, long-term outcomes have been limited by glenoid component aseptic loosening and polyethylene (PE) wear. Previous attempts to improve glenoid fixation with metal-backed glenoids resulted in inferior results. Newer component designs that contain porous metal allow for biological ingrowth of the prosthesis, potentially improving longevity and overall outcomes. Porous metal can also improve humeral component fixation, obviating the need for cement and simplifying revision surgery. Advances such as highly cross-linked polyethylene (HXLPE), vitamin E-doped HXLPE, and alternate bearing surfaces like ceramics and pyrolytic carbon have proven to provide superior wear characteristics in other joint replacements and may prove beneficial in the shoulder as well.

Sports- and Work-Related Outcomes After Shoulder Hemiarthroplasty

BACKGROUND

With an active aging population, more patients expect to return to previous activities and work after surgery.

PURPOSE

To determine the rate and timing to return of sports and employment after shoulder hemiarthroplasty.

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

This was a retrospective review of consecutive patients who underwent shoulder hemiarthroplasty from 2007 to 2013. Follow-up consisted of a patient-reported questionnaire regarding physical fitness, sporting activities, and work status.

RESULTS

From 105 patients screened, 79 were available for follow-up. The average follow-up time was 63.1 months, and the average age at follow-up was 69 years. Scores on the visual analog scale for pain improved from 6.2 to 2.1 (P < .001) postoperatively, and those on the American Shoulder and Elbow Surgeons (ASES) shoulder assessment improved from 34.6 to 71.3 (P < .001). Patients older than 65 years had significantly lower absolute postoperative ASES scores (P = .041) but experienced similar improvement from their preoperative baseline (P = .158) compared with patients younger than 65 years. There were 58 patients who played sports preoperatively, and 67.2% of these restarted at least 1 of their previous sports postoperatively. The average time to return to full sports was 6.5 months for those who returned. Direct rates of return were as follows: fitness sports (69%), swimming (65%), running (64%), cycling (63%), and doubles tennis (57%). Younger age was associated with highest demand level achieved (P = .023). Forty-nine patients worked preoperatively, with 69.4% returning to previous employment after surgery; the average time to return to work was 1.4 months. In comparative analysis, patients who did not return to work had a higher mean body mass index (32 ± 7 vs 27 ± 5 kg/m(2); P < .008).

CONCLUSION

In this hemiarthroplasty cohort, there was a 67.2% rate of return to 1 or more sports at an average of 6.5 months postoperatively. Patients older than 65 years experienced similar improvements in ASES scores compared with patients younger than 65 years, although absolute scores were lower on average. Those who returned to higher demand sports were younger on average. Of patients working preoperatively, 69.4% returned to their previous employment at an average of 1.4 months. Patients who did not return to employment had significantly higher body mass index on average. These findings will help surgeons manage expectations of shoulder hemiarthroplasty candidates preoperatively.

Radiographic and clinical outcomes of total shoulder arthroplasty with an all-polyethylene pegged bone ingrowth glenoid component: prospective short- to medium-term follow-up

BACKGROUND

Glenoid components often cause total shoulder arthroplasty failure. This study examines short-term to midterm radiographic and clinical results of a hybrid glenoid component with 3 cemented peripheral pegs and a central peg, which allows biologic fixation with use of native humeral head autograft.

METHODS

In 4 years, 80 glenoid components were implanted during primary total shoulder arthroplasty with at least 2-year follow-up data. Within 12 months, 4 shoulders were revised and excluded from final analyses. Seven patients did not complete their questionnaires. Outcomes data included the American Shoulder and Elbow Surgeons (ASES) questionnaire, Constant score, and satisfaction score. A shoulder and elbow fellowship-trained surgeon, not involved in the care of these patients, analyzed radiographs for radiolucent lines, glenoid seating, and radiodensity in between the flanges of the central peg.

RESULTS

Only 1 of 80 shoulders was revised for aseptic glenoid loosening. At final follow-up, 81.6% had a radiolucency grade of 0 or 1. Nearly 90% had a glenoid seating grade of A or B. Grade 2 or 3 bone around the central peg was seen in 88.2%. No statistical association existed between Walch glenoid types and radiolucency grades, bone grades around the central peg, perfect radiolucency grade, seating grade, and grade 3 bone around the central peg. There was significant improvement in mean ASES score, adjusted ASES pain score, Constant score, and satisfaction score as well as in forward flexion, abduction, and external rotation.

CONCLUSIONS

The hybrid glenoid can produce stable radiographic and clinical outcomes at short- to medium-term follow-up.

Factors predicting postoperative range of motion for anatomic total shoulder arthroplasty

BACKGROUND

Total shoulder arthroplasty (TSA) has repeatedly been shown to be an effective and durable treatment option for end-stage arthritis with good long-term survivorship. Whereas pain relief is typically the primary goal, improvements in range of motion are typically expected as well. The factors that influence postoperative motion have not been well characterized. The purpose of the study was to examine the factors that influence ultimate postoperative motion after TSA.

METHODS

A retrospective review was conducted of prospectively collected data of 230 patients with minimum 1-year follow-up after TSA for end-stage arthropathy with an intact rotator cuff. Analysis was focused on factors that may correlate with postoperative measured forward flexion, abduction, external rotation, and internal rotation. Included in this analysis was perception of motion, age, body mass index (BMI), comorbidities (smoking, diabetes, osteoporosis, hypercholesterolemia, inflammatory arthritis, and thyroid disease), and number of comorbidities.

RESULTS

Preoperative motion in all directions was predictive of postoperative motion for forward flexion (R = 0.235; P < .001), abduction (R = 0.363; P < .001), external rotation (R = 0.325; P < .001), and internal rotation (R = 0.213; P = .002). BMI and diabetes both negatively correlated with internal rotation (R = -0.134, P = .40 and R = -0.196, P = .003, respectively). Individual and total number of comorbidities were not predictive of postoperative motion. The patient's perception of preoperative motion also did not correlate with postoperative motion.

CONCLUSIONS

Preoperative range of motion before TSA is most predictive of final motion achieved. Individual and total number of comorbidities are not predictive of postoperative motion. Patients with high diabetes and increased BMI have limited postoperative internal rotation.

Outcomes of anatomic shoulder arthroplasty in primary osteoarthritis in type B glenoids

BACKGROUND

Primary glenohumeral osteoarthritis with posterior wear of the glenoid and posterior subluxation of the humerus (Walch type B) presents a challenge to the treating surgeon. Our hypothesis was that glenoids with biconcavity (B2) would be associated with worse outcomes (functional scores and complications) than B1 glenoids.

MATERIALS AND METHODS

We retrospectively analyzed prospectively collected data on 112 anatomic total shoulder arthroplasties (104 patients) with B glenoids. Preoperative computed tomography identified 64 B1 glenoids and 48 B2 glenoids (50 and 37 available for follow-up).

RESULTS

A significant difference between B1 and B2 glenoids was noted in average retroversion (11° vs. 16°; P < .001) and average posterior humeral subluxation (65% vs. 75%; P < .001). No significant difference was seen in mean age (69.5 vs. 69.2 years) or body mass index (28.5 vs. 27.4) at time of surgery. At average follow-up of 60 months (range, 23-120 months), glenoid component radiolucencies (51.6%, B1; 47.9%, B2), range of motion, preoperative and postoperative scores of the shortened Disabilities of the Arm, Shoulder, and Hand questionnaire, and patient satisfaction were not significantly different between the 2 groups. Four revisions (4.6%) were documented for acute postoperative infection (2.3%), subscapularis failure (1.1%), and glenoid loosening (1.1%).

CONCLUSIONS

Although biconcave glenoids commonly have more severe retroversion and posterior subluxation of the humerus, we were unable to find a clinical or radiographic difference in outcome of patients with B1 or B2 glenoids treated with anatomic total shoulder arthroplasty at intermediate-term follow-up. Continued clinical and radiographic follow-up of these cohorts will be necessary to assess any future divergence in outcome.

Posterior glenoid wear in total shoulder arthroplasty: eccentric anterior reaming is superior to posterior augment

BACKGROUND

Uncorrected glenoid retroversion during total shoulder arthroplasty may lead to an increased likelihood of glenoid prosthetic loosening. Augmented glenoid components seek to correct retroversion to address posterior glenoid bone loss, but few biomechanical studies have evaluated their performance.

QUESTIONS/PURPOSES

We compared the use of augmented glenoid components with eccentric reaming with standard glenoid components in a posterior glenoid wear model. The primary outcome for biomechanical stability in this model was assessed by (1) implant edge displacement in superior and inferior edge loading at intervals up to 100,000 cycles, with secondary outcomes including (2) implant edge load during superior and inferior translation at intervals up to 100,000 cycles, and (3) incidence of glenoid fracture during implant preparation and after cyclic loading.

METHODS

A 12°-posterior glenoid defect was created in 12 composite scapulae, and the specimens were divided in two equal groups. In the posterior augment group, glenoid version was corrected to 8° and an 8°-augmented polyethylene glenoid component was placed. In the eccentric reaming group, anterior glenoid reaming was performed to neutral version and a standard polyethylene glenoid component was placed. Specimens were cyclically loaded in the superoinferior direction to 100,000 cycles. Superior and inferior glenoid edge displacements were recorded.

RESULTS

Surviving specimens in the posterior augment group showed greater displacement than the eccentric reaming group of superior (1.01 ± 0.02 [95% CI, 0.89-1.13] versus 0.83 ± 0.10 [95% CI, 0.72-0.94 mm]; mean difference, 0.18 mm; p = 0.025) and inferior markers (1.36 ± 0.05 [95% CI, 1.24-1.48] versus 1.20 ± 0.09 [95% CI, 1.09-1.32 mm]; mean difference, 0.16 mm; p = 0.038) during superior edge loading and greater displacement of the superior marker during inferior edge loading (1.44 ± 0.06 [95% CI, 1.28-1.59] versus 1.16 ± 0.11 [95% CI, 1.02-1.30 mm]; mean difference, 0.28 mm; p = 0.009) at 100,000 cycles. No difference was seen with the inferior marker during inferior edge loading (0.93 ± 0.15 [95% CI, 0.56-1.29] versus 0.78 ± 0.06 [95% CI, 0.70-0.85 mm]; mean difference, 0.15 mm; p = 0.079). No differences in implant edge load were seen during superior and inferior loading. There were no instances of glenoid vault fracture in either group during implant preparation; however, a greater number of specimens in the eccentric reaming group were able to achieve the final 100,000 time without catastrophic fracture than those in the posterior augment group.

CONCLUSIONS

When addressing posterior glenoid wear in surrogate scapula models, use of angle-backed augmented glenoid components results in accelerated implant loosening compared with neutral-version glenoid after eccentric reaming, as shown by increased implant edge displacement at analogous times.

CLINICAL RELEVANCE

Angle-backed components may introduce shear stress and potentially compromise stability. Additional in vitro and comparative long-term clinical followup studies are needed to further evaluate this component design.

Consequences of reaming with flat and convex reamers for bone volume and surface area of the glenoid; a basic science study

Background

The effect of reaming on bone volume and surface area of the glenoid is not precisely known. We hypothesize that (1) convex reamers create a larger surface area than flat reamers, (2) flat reamers cause less bone loss than convex reamers, and (3) the amount of bone loss increases with the amount of version correction.

Methods

Reaming procedures with different types of reamers are performed on similar-sized uniconcave and biconcave glenoids created from Sawbones foam blocks. The loss of bone volume, the size of the remaining surface area, and the reaming depth are measured and evaluated.

Results

Reaming with convex reamers results in a significantly larger surface area than with flat reamers for both uniconcave and biconcave glenoids (p = 0.013 and p = 0.001). Convex reamers cause more bone loss than flat reamers, but the difference is only significant for uniconcave glenoids (p = 0.007).

Conclusions

In biconcave glenoids, convex reamers remove a similar amount of bone as flat reamers, but offer a larger surface area while maximizing the correction of the retroversion. In pathological uniconcave glenoids, convex reamers are preferred because of the conforming shape.

Cementless surface replacement hemiarthroplasty for primary glenohumeral osteoarthritis: results of over 5-year follow-up in patients with or without rotator cuff deficiency

BACKGROUND

Cementless surface replacement hemiarthroplasty (CSRHA) is an established treatment for glenohumeral osteoarthritis; however, studies evaluating its role in arthritis with rotator cuff deficiency are limited. This study reviews the outcomes of CSRHA for glenohumeral osteoarthritis with and without rotator cuff tears.

METHODS

41 CSRHA (Mark III Copeland prosthesis) were performed for glenohumeral osteoarthritis with intact rotator cuffs (n = 21) and cuff-deficient shoulders (n = 20). Patients were assessed using Oxford and Constant questionnaires, patient satisfaction, range of motion measurements and by radiography.

RESULTS

Mean age and follow-up were 75 years and 5.1 years, respectively. Functional gains were significantly higher in patients with intact rotator cuffs compared to cuff-deficient shoulders, with Oxford Shoulder Score improving from 18 to 37.5 and 15 to 27 and forward flexion improved from 60° to 126° and 44° to 77° in each group, respectively. Two patients with deficient cuffs had deficient subscapularis tendons; one of which was dislocated anteriorly.

CONCLUSIONS

CSRHA provides significant improvements in pain and function in patients with glenohumeral osteoarthritis. In patients with deficient cuffs, functional gains are limited, and should be considered in low-demand patients where pain is the primary problem. Caution should be taken in patients with a deficient subscapularis as a result of the risk of dislocation.

Metal-backed glenoid implant with polyethylene insert is not a viable long-term therapeutic option

BACKGROUND

The aims of this study were to determine the survival of anatomic total shoulder arthroplasty with uncemented metal-backed (MB) glenoid components with a polyethylene (PE) insert in primary osteoarthritis, to assess the reasons for revision surgery, and to identify patients and diagnostic factors that influence failure rates.

METHODS

Between 1994 and 1999, 165 patients (mean age, 68 years) with primary osteoarthritis were treated with anatomic total shoulder arthroplasty using an uncemented MB/PE glenoid component. Outcomes were assessed both clinically and radiologically with a minimum of 2 years of follow-up. A prosthetic survival curve was constructed with the end point defined as either partial or complete revision, using 100% confidence intervals.

RESULTS

Survival rate free of revision was 46% (100% confidence interval, 32%-54%) at 12 years. At a mean follow-up of 8.5 years (range, 2-16 years), revision was required in 61 patients (37%); 80% of shoulders undergoing revision (49 of 61) had evidence of PE wear. Glenoid loosening (because of osteolysis secondary to wear debris), soft tissue deficiency, and prosthetic instability were the most common modes of failure. Younger patients and biconcave glenoids (with posterior humeral subluxation) have a negative effect on implant survival. Proximal humerus osteolysis was significantly more frequent in shoulders with PE wear. Exchange of the PE insert (with conservation of the MB tray) was possible in only 3% of the revised shoulders.

CONCLUSION

Uncemented MB glenoid resurfacing is not a viable long-term therapeutic option because of accelerated PE wear leading to early revision surgery. Conservation of the MB tray with reinsertion of a new PE insert is rarely possible because of glenoid bone loss, implant loosening, soft tissue deficiency, and prosthetic instability. Younger patients and biconcave glenoids have a negative effect on implant survival.

Predictors of extended length of stay after elective shoulder arthroplasty

BACKGROUND

With policymakers and hospitals increasingly looking to cut costs, length of stay after surgery has come into focus as an area for improvement. Despite the increasing popularity of total shoulder arthroplasty, there is limited research about the factors contributing to prolonged hospital stay. We sought to identify preoperative and postoperative predictors of prolonged hospital stay in patients undergoing anatomic total shoulder arthroplasty (ATSA) and reverse total shoulder arthroplasty (RTSA).

METHODS

Using the 2011 Nationwide Inpatient Sample, we identified an estimated 40,869 patients who underwent elective total shoulder arthroplasty (62.5% ATSA; 37.5% RTSA) and separated them into those with normal length of stay (<75th percentile) and prolonged length of stay (>75th percentile). Multivariate logistic regression modeling was performed to identify factors associated with prolonged length of stay.

RESULTS

Patient-level factors associated with prolonged length of stay common to patients undergoing ATSA or RTSA included increasing age, female sex, congestive heart failure, renal failure, chronic pulmonary disease, and preoperative anemia. Provider-related factors were lower volume and location in the South or Northeast. Postoperative complications showed a significant influence as well.

CONCLUSION

Our data can be used to promptly identify patients at higher risk of prolonged hospitalization after elective shoulder arthroplasty and to ultimately improve quality of care and cost containment.

Anatomic and Reverse Total Shoulder Arthroplasty in Patients Older Than 80 Years

Anatomic total shoulder arthroplasty (TSA) and reverse total shoulder arthroplasty (RSA) are routinely performed in patients older than 80 years. Often unaware of the differences between the 2 procedures, patients may expect similar outcomes from these procedures. This article reports the outcomes of primary TSA and RSA in patients older than 80 years, with attention directed toward differences in outcomes between the procedures. The authors evaluated a consecutive series of patients who were at least 80 years old and were treated with primary shoulder arthroplasty and had a minimum follow-up of 2 years. Of these patients, 18 underwent primary TSA for osteoarthritis and 33 underwent primary RSA for rotator cuff tear arthropathy. Pain scores, function scores, and range of motion were evaluated preoperatively and at final follow-up. Perioperative and postoperative complications, transfusion rates, length of stay, and subjective satisfaction with the outcome were reported. In these patients, TSA and RSA were similarly effective in improving pain scores, functional scores, and range of motion measurements. Patients who had TSA reported significantly greater satisfaction with surgery and had superior American Shoulder and Elbow Society total and function scores, forward elevation, and external rotation, but similar net improvement from preoperative levels. Although no significant differences were shown in complications, length of stay, or requirement for transfusion, patients treated with RSA had higher rates of transfusion and postoperative complications. Both procedures were similarly effective treatments for patients older than 80 years and showed similar improvements in pain, function, and motion. Patients undergoing RSA were less likely to have good to excellent results, with higher complication and transfusion rates.

Greater patient confidence yields greater functional outcomes after primary total shoulder arthroplasty

BACKGROUND

Patient satisfaction is increasingly being tied to reimbursement rates, and patient satisfaction is often associated with improving functionality and decreasing disability postoperatively. This study sought to determine if a total shoulder arthroplasty patient's preoperative confidence in his or her ability to attain the level of activity desired would influence postoperative functional scores.

MATERIALS AND METHODS

Patients undergoing a primary total shoulder arthroplasty at a single institution were asked to complete a preoperative questionnaire with multiple items including baseline symptom severity measures and their confidence in reaching their level of desired functionality postoperatively (scored 0-10). Patients then completed an identical postoperative questionnaire at their follow-up visits. Associations between the patient's confidence in attaining treatment goals and functional outcomes was established by multiple linear regression models that were adjusted for gender, age, body mass index, baseline 12-Item Short Form Health Survey mental component scores, college education, smoking status, baseline functional scores, and length of follow-up.

RESULTS

Patients had a high level of confidence that their outcome would match their expectations, with an average score of 7.8 (range, 0-10; 28.4% reported a full 10/10 confidence). For every 1-point increase in confidence, patients experienced an average increase in their function score of 2.7 points (P = .039) and improvement in their pain score of 2.0 (P = .033) according to the Penn Shoulder Score. There was no significant association with the patient's 12-Item Short Form Health Survey score postoperatively.

CONCLUSIONS

Patients with greater preoperative confidence actually have significantly better postoperative functional outcomes than their less confident peers even with adjustment for other known risk factors.

Self-assessed and radiographic outcomes of humeral head replacement with nonprosthetic glenoid arthroplasty

BACKGROUND

Active and young patients who place frequent demands on their shoulder present a treatment dilemma when glenohumeral arthritis progresses to a point at which surgical intervention is considered. Humeral head replacement with nonprosthetic glenoid arthroplasty ("ream-and-run") has been proposed to address the limitations of total shoulder arthroplasty and hemiarthroplasty in this population. Several reports from a single institution have shown substantial improvement in self-assessed comfort and function after this procedure. However, to the best of our knowledge, no clinical results pertaining to this technique have been reported from other institutions.

METHODS

Hemiarthroplasty with nonprosthetic glenoid arthroplasty was performed in 17 patients with a minimum 2-year follow-up. Patients were clinically evaluated preoperatively and postoperatively with physical examination, Simple Shoulder Test (SST), American Shoulder and Elbow Surgeons score, visual analog scale, and standardized radiographs. Preoperative radiographs and patient demographics were assessed for correlation with outcome measures.

RESULTS

Improvement of >30% of preoperative SST score was noted in 14 of 17 patients at a mean follow-up of 3.9 years (range, 2.0-6.8 years). SST score improved from mean 3.2 ± 3.1 preoperatively to 10.0 ± 2.6 at latest follow-up (P < .0001). American Shoulder and Elbow Surgeons score improved from mean 42 ± 23 to 90 ± 13 (P < .0001). Male patients had higher SST scores (P = .03) and greater external rotation (P = .03) at latest follow-up.

CONCLUSIONS

Nonprosthetic glenoid arthroplasty demonstrated results that correlate with prior data published by the center at which the procedure was initially described. Patients with concentric glenoid morphology preoperatively did not demonstrate results superior to those of patients with eccentric glenoids.

Surgical Treatment Options for Glenohumeral Arthritis in Young Patients: A Systematic Review and Meta-analysis

PURPOSE

The aim of this study was to compare surgical treatment options for young patients with glenohumeral arthritis.

METHODS

A systematic review of the English-language literature was conducted by searching PubMed, EMBASE, and Scopus with the following term: "(shoulder OR glenohumeral) AND (arthritis OR osteoarthritis) AND (young OR younger)." Studies that reported clinical or radiological outcomes of nonbiologic surgical treatment of generalized glenohumeral arthritis in patients younger than 60 years of age were included. Data were extracted to include study and patient characteristics, surgical technique, outcome scores, pain relief, satisfaction, functional improvement, return to activity, health-related quality of life, complications, need for and time to revision, range of motion, and radiological outcomes. Study quality was assessed with the Modified Coleman Methodology Score.

RESULTS

Thirty-two studies containing a total of 1,229 shoulders met the inclusion criteria and were included in the review. Pain scores improved significantly more after total shoulder arthroplasty (TSA) than after hemiarthroplasty (HA) (P < .001). Patient satisfaction was similar after HA and TSA. Revision surgery was equally likely after HA, TSA, and arthroscopic debridement (AD). Complications were significantly less common after AD than after HA (P = .0049) and TSA (P < .001). AD and TSA afforded better recovery of active forward flexion and external rotation than did HA. At radiological follow-up, subluxation was similarly common after HA and TSA.

CONCLUSIONS

According to current Level IV data, TSA provides greater improvement of pain and range of motion than does HA in the surgical treatment of young patients with glenohumeral arthritis. AD is an efficacious and particularly safe alternative in the short term for young patients with concerns about arthroplasty.

LEVEL OF EVIDENCE

Level IV, systematic review of Level IV studies.

What Are Risk Factors for 30-day Morbidity and Transfusion in Total Shoulder Arthroplasty? A Review of 1922 Cases

BACKGROUND

Total shoulder arthroplasty (TSA) is an effective treatment for end-stage glenohumeral joint pathology with good long-term results. Previous descriptions of morbidity and blood transfusion in TSA are limited by preoperative risk factors and postoperative complications considered and single-center studies.

QUESTIONS/PURPOSES

The purpose of this study was to define in a group of patients undergoing TSA (1) the type and incidence of complications; (2) the frequency of and risk factors for both minor and major complications; and (3) the risk factors for bleeding resulting in transfusion.

METHODS

We retrospectively queried the National Surgical Quality Improvement Program database using Current Procedural Terminology billing codes and identified 1922 cases of TSA performed between 2006 and 2011. Postoperative outcomes were divided into one of four categories: any complication, major morbidity (systemic life-threatening event or a substantial threat to a vital organ) or mortality, minor morbidity (localized to the operative upper extremity or not posing a major systemic threat to the patient), or bleeding resulting in transfusion. Univariate and multivariate analyses were then used to identify risk factors for complications.

RESULTS

There were a total of 155 complications (8% of the 1922 patients identified). The most common complication was bleeding resulting in transfusion (82 patients [4.26%]) followed by urinary tract infections (27 patients [1.40%]), return to the operating room (14 patients [0.73%]), pneumonia (10 patients [0.52%]), and peripheral nerve injury (nine patients [0.47%]). The incidence of major morbidity was 2% (44 patients), which included five patients (0.26%) who died; the incidence of any minor morbidity was 7% (136 patients). After controlling for likely confounding variables, we found steroid use (odds ratio [OR], 3; 95% confidence interval [CI], 2-6), hematocrit < 38% (OR, 2; 95% CI, 1-3), American Society of Anesthesiologists (ASA) Class 4 (OR, 3; 95% CI, 1-7), and operating time > 2 hours (OR, 2; 95% CI, 1-3) as independent predictors of complication and congestive heart failure (OR, 12; 95% CI, 1-106) as an independent risk factor for major morbidity or mortality. Hematocrit < 38% (OR, 3; 95% CI, 2-6), resident involvement (OR, 3; 95% CI, 2-5), steroid use (OR, 3; 95% CI, 1-6), and ASA Class 3 versus 1 or 2 (OR, 2; 95% CI, 1-5) were independent risk factors for bleeding resulting in transfusion.

CONCLUSIONS

Short-term morbidity after TSA is higher than previously reported. The prevalence of complications within 30 days of surgery and our outlined risk factors should guide surgeon-driven preoperative patient evaluation, management, and counseling. Surgeons who perform TSA should be aware operative time > 2 hours is associated with increased complications. Patients with preoperative hematocrit < 38%, history of steroid use, ASA Class > 2, and patients with congestive heart failure should receive medical optimization before TSA.

LEVEL OF EVIDENCE

Level III, therapeutic study.

Can the ream and run procedure improve glenohumeral relationships and function for shoulders with the arthritic triad?

BACKGROUND

The arthritic triad of glenoid biconcavity, glenoid retroversion, and posterior displacement of the humeral head on the glenoid is associated with an increased risk of failure of total shoulder joint replacement. Although a number of glenohumeral arthroplasty techniques are being used to manage this complex pathology, problems with glenoid component failure remain. In that the ream and run procedure manages arthritic pathoanatomy without a glenoid component, we sought evidence that this procedure can be effective in improving the centering of the humeral head contact on the glenoid and in improving the comfort and function of shoulders with the arthritic triad without the risk of glenoid component failure.

QUESTIONS/PURPOSES

We asked, for shoulders with the arthritic triad, whether the ream and run procedure could improve glenohumeral relationships as measured on standardized axillary radiographs and patient-reported shoulder comfort and function as recorded by the Simple Shoulder Test.

METHODS

Between January 1, 2006 and December 14, 2011, we performed 531 primary anatomic glenohumeral arthroplasties for arthritis, of which 221 (42%) were ream and run procedures. Of these, 30 shoulders in 30 patients had the ream and run procedure for the arthritic triad and had two years of clinical and radiographic follow-up. These 30 shoulders formed the basis for this case series. The average age of the patients was 56 ± 8 years; all but one were male. Two of the 30 patients requested revision to total shoulder arthroplasty within the first year after their ream and run procedure because of their dissatisfaction with their rehabilitation progress. For the 28 shoulders not having had a revision, we determined on the standardized axillary views before and after surgery the glenoid type, glenoid version (90° minus the angle between the plane of the glenoid face and the plane of the body of the scapula), and location of the humeral contact point with respect to the anteroposterio dimension of the glenoid (the ratio of the distance from the anterior glenoid lip to the contact point divided by the distance between the anterior and posterior glenoid lips). We also recorded the patient's self-assessed shoulder comfort and function before and after surgery using the 12 questions of the Simple Shoulder Test.

RESULTS

For the 28 unrevised shoulders the mean followup was 3.0 years (range, 2-9.2 years). In these patients, the ream and run procedure resulted in improved centering of the humeral head on the face of the glenoid (preoperative: 75% ± 7% posterior; postoperative: 59% ± 10% posterior; mean difference 16% [95% CI, 13%-19%]; p < 0.001), notably this improved centering was achieved without a significant change in the glenoid version. Patient-reported function was improved (preoperative Simple Shoulder Test: 5 ± 3, postoperative Simple Shoulder Test: 10 ± 4, mean difference 5 [95% CI, 4-6], p < 0.001).

CONCLUSIONS

For shoulders with the arthritic triad, the ream and run procedure can provide improvement in humeral centering on the glenoid and in patient-reported shoulder comfort and function without the risk of glenoid component failure. In that ream and run is a new procedure, substantial additional clinical research with long-term follow-up is needed to define specifically the shoulder characteristics, the patient characteristics and the technical details that are most likely to lead to durable improvements in the comfort and function of shoulders with the challenging pathology known as the arthritic triad.

LEVEL OF EVIDENCE

Level IV, therapeutic study.

Anatomic shoulder arthroplasty: an update on indications, technique, results and complication rates

A shoulder replacement is indicated in patients affected by glenohumeral arthropathy with severely reduced range of motion, persistent pain, especially at night, and loss of strength. There is much discussion in the scientific community about the prosthetic options for these cases: hemiarthroplasty, anatomic total shoulder arthroplasty, and reverse total shoulder arthroplasty. We analyzed the indications for, results of, and complications associated with this kind of surgery, focusing on anatomic arthroplasty and on the concept of modularity.

Management of complications after total shoulder arthroplasty

The outcomes of total shoulder arthroplasty (TSA) for painful arthritis of the glenohumeral joint are excellent with significant improvement in pain and function. Increased use of total shoulder arthroplasty over the past decade has led to identification of common complications. Although the complication rate is low, accurate and timely diagnosis, appropriate management, and implementation of methods for prevention are critical to a successful long-term outcome. The most common complications include infection, glenoid and humeral component loosening, rotator cuff tear, periprosthetic fracture, and neurologic injury. The purpose of this review is to outline the best practices for diagnosing, managing, and preventing these complications.

Outcomes after shoulder replacement: comparison between reverse and anatomic total shoulder arthroplasty

BACKGROUND

Anatomic total shoulder arthroplasty (TSA) and reverse total shoulder arthroplasty (RTSA) are increasingly common procedures employed to treat arthritic conditions. Although TSA is a widely accepted procedure for glenohumeral arthritis with intact rotator cuff, concerns about RTSA persist because of variable complication rates and outcomes.

METHODS

This is a prospective, case-control study comparing outcomes and complications after TSA and RTSA. The study included 47 patients undergoing TSA for glenohumeral arthritis and 53 patients undergoing RTSA for rotator cuff tear arthropathy. Average clinical follow-up was more than 2 years in both groups. Major complications included infection, periprosthetic fracture, instability, glenoid loosening, and need for revision surgery. Patient outcome measures included the American Shoulder and Elbow Surgeons score, pain visual analog scale score, and goniometer-measured range of motion. Plain radiographs were reviewed to assess for degree of glenoid lucency in TSA and scapular notching in RTSA.

RESULTS

At 2 years, there were no differences in rate of major complications (TSA, 15%; RTSA, 13%; P = .808) or revision surgeries (TSA, 11%; RTSA, 9%). Outcomes assessed by the American Shoulder and Elbow Surgeons score and visual analog scale were also similar between the 2 groups. TSA patients had greater external rotation than RTSA patients did (53° vs 38°; P = .001). Otherwise, forward flexion, abduction, and internal rotation were comparable in range of motion.

CONCLUSIONS

TSA and RTSA have similar complication rates, need for revision, patient-reported outcomes, and range of motion at 2 years of follow-up. The use of side-by-side cohorts in this study allows standardized comparison between these 2 shoulder arthroplasty procedures.

Reliability and accuracy of digital templating for the humeral component of total shoulder arthroplasty

BACKGROUND

This experimental study evaluated the interobserver reliability and accuracy of pre-operative digital templating for humeral head size, stem size and neck angle for total shoulder arthroplasty.

METHODS

Twenty-five patients underwent a total shoulder arthroplasty with a single prosthesis. Four independent, blinded surgeons (two experienced shoulder surgeons and two PGY-6 fellows) used pre-operative radiographs and templating software to generate templates of the humeral head, stem and neck for each patient. Interobserver reliability was calculated using weighted kappa (κ) analysis. Accuracy was assessed by comparing templates to actual implant sizes.

RESULTS

Interobserver reliability was fair to substantial (κ = 0.26 to 0.71) for head size, fair to substantial (κ = 0.39 to 0.72) for stem size and slight to fair (κ = 0.16 to 0.34) for neck angle. Templated head size, stem size and neck angle had accuracies of 53%, 77% and 68% within one size variation, respectively. Experience did not affect accuracy (p = 0.11 to 0.48).

CONCLUSIONS

Digital templating is not a useful guide for pre-operative surgical planning and should not be used to select a prosthesis.

Analysis of perioperative complications in patients after total shoulder arthroplasty and reverse total shoulder arthroplasty

BACKGROUND

Data directly comparing the perioperative complication rates between total shoulder arthroplasty (TSA) and reverse total shoulder arthroplasty (RTSA) are limited.

METHODS

The Nationwide Inpatient Sample database, which comprises data from a statistically representative sample of hospitals across the United States, was analyzed for the years 2010 and 2011. The International Classification of Diseases, Ninth Revision procedure codes differentiated the patients who received TSA (81.80) and RTSA (81.88). Demographic data, comorbidities, perioperative complications, and hospitalization data were compared.

RESULTS

This retrospective analysis included 19,497 patients, with 14,031 patients in the TSA group and 5466 patients in the RTSA group. Patients who underwent RTSA were older (P < .001), were more likely to be female (P < .001), and had increased rates of fracture (P < .001). The RTSA group had significantly higher perioperative rates of mortality (P = .004), pneumonia (P < .001), deep venous thrombosis (P < .001), myocardial infarction (P = .005), urinary tract infection (P < .001), and blood transfusions (P < .001). In addition, the RTSA patients had longer hospital stays (P < .001) and higher hospital charges (P < .001). The rates of comorbidities were also higher in the patients who underwent RTSA. After adjustment for these differences in comorbidities and surgical indications with our multivariate analysis, RTSA was still independently associated with increased hospital charges (difference of $11,530; P < .001), longer hospitalization (difference of 0.24 day; P < .001), more blood transfusions (relative risk, 1.43; P < .001) and higher rates of pneumonia (relative risk, 1.61; P = .04) and deep venous thrombosis (relative risk, 2.24; P = .01).

CONCLUSION

We found that RTSA patients, compared with TSA patients, had significantly longer length of stay, higher hospital charges that are not completely attributable to increased implant costs alone, and increased rates of perioperative complications.

Speed of recovery after shoulder arthroplasty: a comparison of reverse and anatomic total shoulder arthroplasty

BACKGROUND

Whereas patient expectations after anatomic total shoulder arthroplasty (TSA) and reverse shoulder arthroplasty (RSA) relate to sustained improvements in pain, function, and motion, the time necessary to reach these goals is unclear. Our purpose was to investigate the speed of recovery and to compare the effectiveness of primary TSA and RSA.

METHODS

We analyzed (preoperative, 3 month, 6 month, 1-year, and 2-year scores) pain scores, functional scores, and motion for 122 patients treated with primary RSA and 166 patients treated with primary TSA with a minimum of 1 year of follow-up. Comparisons were made to determine the effectiveness of treatment, time required to reach a plateau in improvement, and percentage of overall improvement at 3 and 6 months.

RESULTS

Significant improvements were observed for both TSA and RSA at all intervals (P < .001), except with internal rotation for RSA. Pain relief was rapid after both TSA and RSA. TSA patients reached a consistent plateau for pain and function by 6 months and for shoulder elevation by 1 year. RSA patients demonstrated variability with multiple false plateau points. By 6 months, TSA patients had achieved 90% to 100% of functional improvement, whereas RSA patients reached 72% to 91%. The effectiveness of TSA was greater than that of RSA for all measures with the exception of elevation and abduction.

CONCLUSION

Whereas patients treated with primary TSA and RSA can expect rapid improvements in pain, those treated with TSA can anticipate a more consistent and effective recovery of pain, function, and shoulder rotation. Patients receiving RSA can expect a variable length of recovery with greater improvements in forward elevation and abduction.

Stemmed versus stemless total shoulder arthroplasty: a preliminary report and short-term results

BACKGROUND

Although several studies have been performed on the use of various devices in total shoulder arthroplasty (TSA), no data are available in order to establish whether to prefer stemmed or stemless humeral components. Thus, the purpose of our study was to evaluate the short-term functional outcome in a cohort of subjects treated with TSA randomized to treatment with stemmed or stemless prosthesis.

METHODS

In this prospective longitudinal study, we randomized to treatment with stemmed (group 1) or with stemless (group 2) humeral component in nineteen subjects (2 M and 17 F) diagnosed with humeral primary osteoarthritis with indication to TSA. We evaluated the range of movement of all the participants and the functional outcome using Constant score and simple shoulder test (SST) before and after 2 years from surgery.

RESULTS

No differences were detected after 2 years from surgery in the two groups in terms of functional scores and range of motion (p > 0.05).

CONCLUSION

Stemmed and stemless prostheses are comparable in terms of functional outcome. These data might be useful for the surgeon in order to choose more tissues-paring methodologies and less invasive procedures, such as stemless humeral implants.

The contribution of reverse shoulder arthroplasty to utilization of primary shoulder arthroplasty

BACKGROUND

We assessed the contribution of reverse shoulder arthroplasty to overall utilization of primary shoulder arthroplasty and present age- and sex-stratified national rates of shoulder arthroplasty. We also assessed contemporary complication rates, mortality rates, and indications for shoulder arthroplasty, as well as estimates and indications for revision arthroplasty.

METHODS

We used the Nationwide Inpatient Samples for 2009 through 2011 to calculate estimates of shoulder arthroplasty and assessed trends using Joinpoint (National Cancer Institute, Bethesda, MD) regression.

RESULTS

The cumulative estimated utilization of primary shoulder arthroplasty (anatomic total shoulder arthroplasty, hemiarthroplasty, and reverse shoulder arthroplasty) increased significantly from 52,397 procedures (95% confidence interval [CI], 47,093-57,701) in 2009 to 67,184 cases (95% CI, 60,638-73,731) in 2011. Reverse shoulder arthroplasty accounted for 42% of all primary shoulder arthroplasty procedures in 2011. The concomitant diagnosis of osteoarthritis and rotator cuff impairment was found in only 29.8% of reverse shoulder arthroplasty cases. The highest rate of reverse shoulder arthroplasty was in the 75- to 84-year-old female subgroup (77 per 100,000 persons; 95% CI, 67-87). Revision cases comprised 8.8% and 8.2% of all shoulder arthroplasties in 2009 and 2011, respectively, and 35% of revision cases were because of mechanical complications/loosening whereas 18% were because of dislocation.

CONCLUSIONS

The utilization of primary shoulder arthroplasty significantly increased in just a 3-year time span, with a major contribution from reverse shoulder arthroplasty in 2011. Indications appear to have expanded because a large percentage of patients did not have rotator cuff pathology. The burden from revision arthroplasties was also substantial, and efforts to optimize outcomes and longevity of primary shoulder arthroplasty are needed.

A novel osteotomy in shoulder joint replacement based on analysis of the cartilage/metaphyseal interface

BACKGROUND

The accuracy of reconstruction is thought to impact on functional outcome following glenohumeral joint arthroplasty. The objective of this study was to define an area of minimal anatomic variation at the cartilage/metaphyseal interface of the proximal humerus to optimize the osteotomy of the humeral head, enabling accurate reconstruction with a prosthetic component.

METHODS

Hand held digitization and 3D surface laser scanning techniques were used to digitize 24 cadaveric arms and determine the normal geometry. Each humeral head was then examined to identify the most consistent anatomical landmarks for the ideal osteotomy plane to optimize humeral component positioning.

FINDINGS

The novel, posterior referencing, osteotomy resulted in a mean increase in retroversion of only 0.4° when compared to the original geometry. A traditional anterior referencing osteotomy, by comparison, produced a mean increase in retroversion of 11°. In addition, the novel osteotomy only increased axial diameter by 0.71mm and head height by 0.02mm compared to an anterior referencing osteotomy (3.0mm and 2.7mm respectively).

INTERPRETATION

The traditional osteotomy, referencing the anterior border of the cartilage/metaphyseal interface potentially resulted in an increase in prosthetic head size and retroversion. The novel osteotomy, referencing from the posterior cartilage/metaphyseal interface enabled a more accurate recovery of head geometry. Importantly, the increase in retroversion created by the traditional osteotomy was not replicated with the novel technique. Referencing from the posterior cartilage/metaphyseal interface produced a more reliable osteotomy, more closely matching the original humeral geometry.

LEVEL OF EVIDENCE

Basic Science, Anatomic study, Computer model.

High incidence of hemiarthroplasty for shoulder osteoarthritis among recently graduated orthopaedic surgeons

BACKGROUND

Primary glenohumeral osteoarthritis is a common indication for shoulder arthroplasty. Historically, both total shoulder arthroplasty (TSA) and hemi-shoulder arthroplasty (HSA) have been used to treat primary glenohumeral osteoarthritis. The choice between procedures is a topic of debate, with HSA proponents arguing that it is less invasive, faster, less expensive, and technically less demanding, with quality of life outcomes equivalent to those of TSA. More recent evidence suggests TSA is superior in terms of pain relief, function, ROM, strength, and patient satisfaction. We therefore investigated the practice of recently graduated orthopaedic surgeons pertaining to the surgical treatment of this disease.

QUESTIONS/PURPOSES

We hypothesized that (1) recently graduated, board eligible, orthopaedic surgeons with fellowship training in shoulder surgery are more likely to perform TSA than surgeons without this training; (2) younger patients are more likely to receive HSA than TSA; (3) patient sex affects the choice of surgery; (4) US geographic region affects practice patterns; and (5) complication rates for HSA and TSA are not different.

METHODS

We queried the American Board of Orthopaedic Surgery's database to identify practice patterns of orthopaedic surgeons taking their board examination. We identified 771 patients with primary glenohumeral osteoarthritis treated with TSA or HSA from 2006 to 2011. The rates of TSA and HSA were compared based on the treating surgeon's fellowship training, patient age and sex, US geographic region, and reported surgical complications.

RESULTS

Surgeons with fellowship training in shoulder surgery were more likely (86% versus 72%; OR 2.32; 95% CI, 1.56-3.45, p<0.001) than surgeons without this training to perform TSA rather than HSA. The mean age for patients receiving HSA was not different from that for patients receiving TSA (66 versus 68, years, p=0.057). Men were more likely to receive HSA than TSA when compared to women (RR 1.54; 95% CI, 1.19-2.00, p=0.0012). The proportions of TSA and HSA were similar regardless of US geographic region (Midwest HSA 21%, TSA 79%; Northeast HSA 25%, TSA 75%; Northwest HSA 16%, TSA 84%; South HSA 27%, TSA 73%; Southeast HSA 24%, TSA 76%; Southwest HSA 23%, TSA 77%; overall p=0.708). The overall complication rates were not different with the numbers available: 8.4% (15/179) for HSA and 8.1% (48/592) for TSA (p=0.7555).

CONCLUSIONS

The findings of this study are at odds with the recommendations in the current clinical practice guidelines for the treatment of glenohumeral osteoarthritis published by the American Academy of Orthopaedic Surgeons. These guidelines favor using TSA over HSA in the treatment of shoulder arthritis. Further investigation is needed to clarify if these practice patterns are isolated to recently graduated board eligible orthopaedic surgeons or if the use of HSA continues with orthopaedic surgeons applying for recertification.

LEVEL OF EVIDENCE

Level III, therapeutic study. See Instructions for Authors for a complete description of levels of evidence.

Isokinetic strength differences between patients with primary reverse and total shoulder prostheses: muscle strength quantified with a dynamometer

BACKGROUND

Range of motion after total shoulder arthroplasty is better than after reverse shoulder arthroplasty, however with similar clinical outcome. It is unclear if this difference can only be found in the different range of motion or also in the force generating capacity.

QUESTIONS

(1) are isokinetically produced joint torques of reverse shoulder arthroplasty comparable to those of total shoulder arthroplasty? (2) Does this force-generating capacity correlate with functional outcome?

METHODS

Eighteen reverse shoulder arthroplasty patients (71years (SD 9years)) (21 shoulders, follow-up of 21months (SD 10months)) were recruited, 12 total shoulder arthroplasty patients (69years (SD 9years)) (14 shoulders, follow-up of 35months (SD 11months)). Pre- and post-operative Constant-Murley scores were obtained; two isokinetic protocols (ab-/adduction and ex-/internal rotations) at 60°/s were performed.

FINDINGS

Twelve of 18 reverse shoulder arthroplasty patients generated enough speed to perform the test (13 shoulders). Mean ab-/adduction torques are 16.3Nm (SD 5.6Nm) and 20.4Nm (SD 11.8Nm). All total shoulder arthroplasty patients generated enough speed (14 shoulders). Mean ab-/adduction torques are 32.1Nm (SD 13.3Nm) and 43.1Nm (SD 21.5Nm). Only 8 reverse shoulder arthroplasty patients (9 shoulders) could perform ex-/internal rotation tasks and all total shoulder arthroplasty patients. Mean ex-/internal rotation torques are 9.3Nm (SD 4.7Nm) and 9.2Nm (SD 2.1Nm) for reverse shoulder arthroplasty, and 17.9Nm (SD 7.7Nm) and 23.5Nm (SD 10.6Nm) for total shoulder arthroplasty. Significant correlations between sub-scores: activity, mobility and strength and external rotation torques for reverse shoulder arthroplasty. Moderate to strong correlation for sub-scores: strength in relation to abduction, adduction and internal rotation torques for total shoulder arthroplasty.

INTERPRETATION

Shoulders with a total shoulder arthroplasty are stronger. This can be explained by the absence of rotator cuff muscles and (probably) medialized center of rotation in reverse shoulder arthroplasty. The strong correlation between external rotation torques and post-operative Constant-Murley sub-scores demonstrates that external rotation is essential for good clinical functioning in reverse shoulder arthroplasty.

Accuracy of patient-specific guided glenoid baseplate positioning for reverse shoulder arthroplasty

BACKGROUND

The accuracy of reproducing a surgical plan during shoulder arthroplasty is improved by computer assistance. Intraoperative navigation, however, is challenged by increased surgical time and additional technically difficult steps. Patient-matched instrumentation has the potential to reproduce a similar degree of accuracy without the need for additional surgical steps. The purpose of this study was to examine the accuracy of patient-specific planning and a patient-specific drill guide for glenoid baseplate placement in reverse shoulder arthroplasty.

METHODS

A patient-specific glenoid baseplate drill guide for reverse shoulder arthroplasty was produced for 14 cadaveric shoulders based on a plan developed by a virtual preoperative 3-dimensional planning system using thin-cut computed tomography images. Using this patient-specific guide, high-volume shoulder surgeons exposed the glenoid through a deltopectoral approach and drilled the bicortical pathway defined by the guide. The trajectory of the drill path was compared with the virtual preoperative planned position using similar thin-cut computed tomography images to define accuracy.

RESULTS

The drill pathway defined by the patient-matched guide was found to be highly accurate when compared with the preoperative surgical plan. The translational accuracy was 1.2 ± 0.7 mm. The accuracy of inferior tilt was 1.2° ± 1.2°. The accuracy of glenoid version was 2.6° ± 1.7°.

CONCLUSION

The use of patient-specific glenoid baseplate guides is highly accurate in reproducing a virtual 3-dimensional preoperative plan. This technique delivers the accuracy observed using computerized navigation without any additional surgical steps or technical challenges.

Short stem shoulder replacement

Context:

It is agreed that it is important to anatomically reproduce the proximal humeral anatomy when performing a prosthetic shoulder replacement. This can be difficult with a long stemmed prosthesis, in particular if there is little relationship of the metaphysis to the humeral shaft. The ‘short stem’ prosthesis can deal with this problem.

Aims:

A prospective study assessed the results of total shoulder arthroplasty using a short stem humeral prosthesis, a ceramic humeral head, and a pegged cemented polyethylene glenoid.

Materials and methods:

Patients with primary shoulder osteoarthritis were recruited into this prospective trial and pre-operatively had the ASES, Constant, SPADI, and DASH scores recorded. The patients were clinically reviewed at the two weeks, eight weeks, one year, and two year mark with completion of a data form. Radiological evaluation was at the eight week, one year and two year follow-up. At the one and two year follow-up the satisfaction rating, the range of passive and active motion, Constant, ASES, SPADI, DASH and pain results were recorded and analysed with SPPS 20.

Results:

During the study period 97 short stem, ceramic head total shoulder replacements were carried out. At the time of follow-up 12 were two years from operation and 38 one year from operation. Active elevation was overall mean 160 degrees. Constant scores were 76 at 1 year, and 86 at 2 years, ASES 88 and 93, and satisfaction 96% and 98% respectively at one and 2 year follow up. There were no problems during insertion of the humeral prosthesis, or any radiolucent lines or movement of the prosthesis on later radiographs.

Conclusion:

The short stem prosthesis had no complications, and on follow up radiographs good bone fixation. These fairly short term clinical results were overall good.

Complications of shoulder arthroplasty for osteoarthritis with posterior glenoid wear

BACKGROUND

Anatomical total shoulder arthroplasty (TSA) for glenohumeral osteoarthritis (OA) and severe posterior glenoid wear may entail early postoperative complications (recurrence of posterior subluxation, glenoid loosening). To avoid these mechanical problems, reverse shoulder arthroplasty (RSA) has recently been proposed, mainly for its intrinsic stability. Our purpose was to present the results of TSA and RSA in glenohumeral OA with posterior glenoid wear of at least 20°.

HYPOTHESIS

By virtue of its constrained design, RSA could prevent recurrence of posterior subluxation and limit the occurrence of mechanical complications.

MATERIALS AND METHODS

A consecutive series of 23 patients (27 shoulders) were treated for glenohumeral OA with total shoulder prostheses: 19 TSAs and 8 RSAs. Mean age was 70 years (range, 47-85 years), mean retroversion angle 28° (20°-50°) and mean subluxation index 74% (57-89%). Constant Score, Subjective Shoulder Value (SSV), QuickDASH and Simple Shoulder Test (SST) were measured, and radiological examinations were performed at a mean follow-up of 52 months (24-95 months).

RESULTS

TSA and RSA patients respectively displayed Constant Scores of 65 and 65, SSV of 79% and 74%, QuickDASH of 16 and 27, and SST of 88 and 78. Two patients underwent surgical revision of TSA because of glenoid loosening; 52% of TSA patients presented complete radiolucent lines and 11% recurrence of posterior subluxation.

CONCLUSION

Complications are frequently observed after shoulder arthroplasty for OA with severe glenoid retroversion. RSA could be an alternative to TSA for selected patients, independently of rotator cuff status. Studies on RSA in this specific indication with longer follow-up are now needed.

LEVEL OF EVIDENCE

Level IV; retrospective case series.

Resurfacing hemiarthroplasty compared to stemmed hemiarthroplasty for glenohumeral osteoarthritis: a randomised clinical trial

PURPOSE

The aim of this study was to conduct a randomised, clinical trial comparing stemmed hemiarthroplasty and resurfacing hemiarthroplasty in the treatment of glenohumeral osteoarthritis.

METHODS

A total of 40 shoulders (35 patients) were randomised to stemmed hemiarthroplasty or resurfacing hemiarthroplasty and evaluated three and 12 months postoperatively using the Constant-Murley score (CMS) and Western Ontario Osteoarthritis of the Shoulder (WOOS) index.

RESULTS

There were no statistically significant differences in age, gender or pre-operative scores except for WOOS at baseline. Two patients were lost to follow-up. Significant improvements in CMS and WOOS were observed at one year after both arthroplasty designs. At one year, the mean CMS was 48.9 (range 6-80) after resurfacing hemiarthroplasty and 59.1 (range 0-88) after stemmed hemiarthroplasty {mean difference 10.2 [95 % confidence interval (CI) -3.3 to 23.6], P = 0.14}. The mean WOOS was 59.2 (range 5.2-100.0) and 79.4 (range 12.8-98.6), respectively [mean difference 20.2 (95 % CI 3.4-36.9), P = 0.02]. No major complications occurred and there were no revisions.

CONCLUSIONS

The effects of resurfacing hemiarthroplasty tended to be inferior to those of stemmed hemiarthroplasty. It is unclear whether this reflects a real difference in effect or baseline differences due to the limited number of randomised patients. We suggest there is a need for a larger, more definitive trial.

A glenoid reaming study: how accurate are current reaming techniques?

BACKGROUND

Correct reaming of a degenerative glenoid can be a difficult procedure. We investigated how the quality of the reamed surface is influenced by different reamers, by the surgeon's experience, and by glenoid erosion patterns.

MATERIAL AND METHODS

Three shoulder surgeons performed reaming procedures with different types of reamers (flat, convex, K-wire guided, and nipple guided) on a series of similarly sized uniconcave and biconcave glenoids. The reproducibility of reaming and the effect of different reamers on different-shaped glenoids were measured and evaluated.

RESULTS

The center and direction of reaming were constant for all surgeons in the case of type A glenoids. For type B2 glenoids, the center and direction of reaming differed significantly between surgeons. The congruity of the reamed surface was better after flat reaming than after convex reaming. Whether the reamers were guided by a central K-wire or by a nipple had no significant effect on the reamed surface. The experience of the surgeon had no effect on the congruity of reaming.

CONCLUSIONS

Reaming of a uniconcave glenoid is reproducible, but reaming of a biconcave glenoid seems much more difficult. Erosion and deformity of the glenoid influence the accuracy of reaming the most. Surgical experience plays a less important role. We conclude that there is a need for guidance in reaming of biconcave glenoids.

Correction of acquired glenoid bone loss in osteoarthritis with a standard versus an augmented glenoid component

BACKGROUND

The magnitude and anatomic consequences of pathologic acquired glenoid retroversion and posterior bone loss that can be surgically corrected with a standard versus an augmented glenoid component have not been studied extensively in a surgical patient population.

MATERIALS AND METHODS

Twenty-nine patients with glenohumeral osteoarthritis, acquired posterior bone loss, and increased retroversion were studied by use of a three-dimensional computer surgical simulation. For each case, amount of medialization was measured as the linear distance from the lateral aspect of the glenoid vault model to the center of the articular implant surface. Simulation of implant placement at 0° or 6° was performed with use of a standard glenoid having a uniform thickness and an asymmetric thickness augmented component.

RESULTS

An increased amount of medialization was seen with the standard glenoid, 8.3 ± 4.1 mm, compared with 3.8 ± 3.3 mm with use of the augmented glenoid implant (P < .001). When glenoid retroversion was corrected to 0°, pathologic version was shown to have strong and significant relationship to the amount of medialization for both the standard (R(2) = 0.825) and augmented (R(2) = -0.68) glenoid implant. There was an increased ability to correct greater amounts of pathologic version with less medialization by use of an augmented step glenoid compared with a standard anchor peg glenoid.

DISCUSSION

Correction of moderate to severe glenoid retroversion by asymmetric reaming cannot always be done with use of a standard component, and if it is done, it will result in greater medialization of the joint line. Use of an augmented component can allow complete correction of retroversion and minimize the effect of medialization.

Outcome and risk of revision following shoulder replacement in patients with glenohumeral osteoarthritis

This thesis includes four studies focusing on the functional outcome, shoulder-specific quality of life and risk of revision following shoulder replacement in patients with glenohumeral osteoarthritis without symptomatic rotator cuff pathology. The Danish version of WOOS, translated according to international standardized guidelines, had substantial psychometric properties comparable to the original version. It is recommendable to use WOOS in the evaluation of patients with glenohumeral osteoarthritis treated with shoulder replacement. Data from DSR showed that the shoulder specific quality of life following total shoulder arthroplasty was superior to that of hemiarthroplasty (resurfacing hemiarthroplasty and stemmed hemiarthroplasty). The difference between stemmed hemiarthroplasty and resurfacing hemiarthroplasty was small and did not exceed the minimal clinically important difference. The revision rate following resurfacing hemiarthroplasty was surprisingly high compared with previous reports but there were no statistical significant differences in revision rate between arthroplasty designs. The shoulder specific quality of life and revision rate in patients under the age of 55 was worrying. The use of resurfacing hemiarthroplasty has relied on the results from case series only. The efficacy in the treatment of glenohumeral osteoarthritis has been promising but the CMS found in the randomized clinical trial indicate that the functional outcome may be inferior to that of stemmed hemiarthroplasty and less favourable than previously reported. However, the limited number of patients may have influenced the results and a larger definitive RCT is needed.Shoulder replacement is relevant and effective in the treatment of glenohumeral osteoarthritis; however, resurfacing hemiarthroplasty was associated with a poorer outcome and a higher risk of revision than previously assumed especially in patients under the age of 55. Based on data from this thesis, and based on existing knowledge, it seems like total shoulder arthroplasty should be preferred in the treatment of glenohumeral osteoarthritis. Shoulder replacement is rarely indicated in younger patients where other treatment options (e.g., physiotherapy; intraarticular injections of hyaluronate; and joint preserving surgery) should be considered until the efficacy of shoulder replacement has been more thoroughly documented.

Effect of glenoid cementation on total shoulder arthroplasty for degenerative arthritis of the shoulder: a review of the New Zealand National Joint Registry

BACKGROUND

Despite the lack of literature showing improved results compared with cemented designs, uncemented glenoid components are still commonly used in total shoulder arthroplasty (TSA). Most studies comparing cemented with uncemented glenoids involve small numbers or include patients with inflammatory arthritis.

METHODS

New Zealand National Joint Registry data was used to compare the outcomes of uncemented and cemented glenoids in TSA performed for degenerative arthritis. Measured variables were the revision rate and the Oxford Shoulder Score (OSS).

RESULTS

Data were retrieved on 1596 patients, with a mean follow-up 3.5 years (range 2-10.7 years), 1065 of whom had a cemented glenoid. There were no significant differences in any preoperative factors between the 2 groups. The revision rate for uncemented glenoids was 4.4 times higher than for cemented glenoids (1.92 vs. 0.44 revisions per 100 component-years, P < .001). Age <55 years was an independent risk factor for revision (P < .001). The most common reason for revision was rotator cuff wear (35.5%) in the uncemented glenoids and loosening (36.3%) in the cemented glenoids. The difference in the mean OSS between the 2 groups was less than 1 point at 6 months (P = .109) and at 5 years (P = .377).

CONCLUSION

Uncemented glenoids had a markedly higher revision rate. Patients aged <55 years have the highest revision rate regardless of glenoid fixation method. The higher revision rate in the uncemented glenoid group persisted when the effect of young age was corrected for. There was no clinically or statistically significant difference in the OSS results for clinical outcome between the two groups.

LEVEL OF EVIDENCE

Level III, retrospective cohort, treatment study.

3D CT assessment of the relationship between humeral head alignment and glenoid retroversion in glenohumeral osteoarthritis

BACKGROUND

Glenoid bone loss associated with advanced glenohumeral arthritis is frequently accompanied by subluxation of the humeral head with subsequent inferior outcomes of shoulder arthroplasty. We hypothesized that the relationship between the center of the humeral head and the perpendicular to the glenoid fossa plane differs from, and is independent of, the relationship between the center of the humeral head and the plane of the scapula.

METHODS

Three-dimensional computed tomography (3D CT) imaging was performed on sixty patients with advanced osteoarthritis and fifteen controls with no osteoarthritis to define the baseline relationship between the center of the humeral head and the perpendicular to the glenoid fossa plane and the plane of the scapula. Correlations between these variables and the amount of bone loss and glenoid version were assessed.

RESULTS

There was a strong linear relationship (p &lt; 0.001) between glenoid retroversion and the center of the humeral head in relation to the center line of the scapula (humeral-scapular alignment). Humeral head alignment in relation to the glenoid plane (humeral-glenoid alignment) was variable and not strongly correlated with the amount of glenoid retroversion. The average glenoid retroversion for the normal shoulders was -3.5°, and the average humeral-scapular alignment offset percentage was -2.3%. The average humeral-glenoid alignment offset for the normal shoulders was 0.5 mm with an average humeral-glenoid alignment offset percentage of 0.9%.

CONCLUSIONS

The location of the humeral head in relation to the glenoid can be defined as displacement from the plane of the scapula and from the perpendicular of the glenoid plane. These two measures are independent of one another. The data suggest that each measurement may represent a different effect on glenoid loading.

CLINICAL RELEVANCE

The importance of this study is that it presents quantitative data and clear guidelines to define two measurements of glenohumeral alignment as separate and important variables. The clinical relevance of these methods will be further defined when they are correlated with clinical outcomes.