Ethical committ

*Reprint req

and Trauma Sur

Viale Europa (L

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J Shoulder Elbow Surg (2013) 22, 1639-1649

1058-2746/$ - s

http://dx.doi.org

www.elsevier.com/locate/ymse

Health-related quality of life and functionality afterreverse shoulder arthroplasty

Roberto Castricini, MDa, Giorgio Gasparini, MDb,*, Francesco Di Luggo, MDb,Massimo De Benedetto, MDa, Marco De Gori, MDb, Olimpio Galasso, MDa

aDepartment of Orthopaedic and Trauma Surgery, Casa di Cura ‘‘Villa Verde,’’ Fermo, ItalybDepartment of Orthopaedic and Trauma Surgery, University ‘‘Magna Græcia,’’ Catanzaro, Italy

Background: Modern semiconstrained reverse shoulder arthroplasty (RSA) has shown a great improve-ment in function and range of motion (ROM) in different etiologies, including revision surgery, sequelaeof fractures, or tumors. Few studies have evaluated RSA for primary glenohumeral osteoarthritis, massiverotator cuff tear, or cuff tear arthropathy excluding any other shoulder disease, and data on patients’ qualityof life after this surgery are lacking.Methods: In this prospective cohort study, 80 patients were evaluated after an RSA for either primary oste-oarthritis, massive rotator cuff tear, or cuff tear arthropathy with the Constant-Murley score (CMS), ROM,and Short Form Health Survey (SF-36). A radiologic assessment was performed preoperatively and post-operatively in 62 of these patients.Results: At a mean 5-year follow-up, the cumulative survival rate was 97.3% and significant improve-ments in the CMS and ROM were observed when compared with the baseline values. The CMS was93.2% of the sex- and age-matched normal values. The postoperative SF-36 scores showed no significantdifferences compared with normative data. Younger patients and subjects with worse preoperative condi-tions achieved the greatest benefit after RSA. The length of follow-up was found to be associated with theseverity of scapular notching.Conclusions: This study introduces new predictors for surgical outcomes, and it shows that patients whohad undergone RSA a mean of 5 years earlier exhibit similar functionality and health-related quality of lifewith respect to healthy controls. Physicians should consider these results when discussing the outcomes ofthis surgery with patients.Level of evidence: Level IV, Case Series, Treatment Study.� 2013 Journal of Shoulder and Elbow Surgery Board of Trustees.

Keywords: Reverse shoulder arthroplasty; primary glenohumeral osteoarthritis; massive rotator cuff tear;

cuff tear arthropathy; Constant-Murley score; SF-36; outcome predictors

10

Reverse shoulder arthroplasty (RSA) is currently gainingmomentum as a satisfactory option for patients withsubstantial shoulder pain and dysfunction who cannot be

ee approval: Casa di Cura ‘‘Villa Verde’’ No. 0045/2002.

uests: Giorgio Gasparini, MD, Department of Orthopaedic

gery, School of Medicine, University ‘‘Magna Græcia,’’

ocalit�a Germaneto), 88100 Catanzaro, Italy.

ss: gasparini@unicz.it (G. Gasparini).

ee front matter � 2013 Journal of Shoulder and Elbow Surgery

/10.1016/j.jse.2013.01.020

reliably treated with conventional arthroplasty. Indeed, anincreasing volume of patients worldwide routinely undergoRSA for a broad spectrum of pathologies.35 After its firstintroduction in the 1970s, the constrained reverse ball-and-socket shoulder prosthesis showed doubtful clinicalsuccess, primarily because of excessive shear forces andthe failure of the glenoid component.35 The semicon-strained RSA was designed by Paul Grammont in 1987,20

Board of Trustees.

Table I Baseline characteristics of patients (N ¼ 80)

Patient data Mean � SD (range) or n (%)

SexFemale 59 (73.8%)Male 21 (26.3%)

Civil statusMarried 54 (67.5%)Widowed 26 (32.5%)

Educational levelIlliteracy 18 (22.5%)Elementary school 51 (63.8%)Middle school 9 (11.3%)High school 2 (2.5%)

EmploymentUnemployed 26 (32.5%)Employed 11 (13.8%)Retired 43 (53.8%)

Previous shoulder surgery 4 (5%)Initial diagnosisMRCT 34 (42.6%)Primary OA 33 (41.3%)CTA 13 (16.3%)

Age at operation (y) 72.54 � 5.03 (61-86)Affected sideRight 56 (70%)Left 24 (30%)

Preoperative Hamada grade1 6 (12.8%)2 20 (42.6%)3 8 (17.0%)4 9 (19.2%)5 4 (8.5%)

Preoperative severity index 1.2 � 0.1 (1-1.6)Follow-up (mo) 60.1 � 18.1 (36-99)

1640 R. Castricini et al.

and despite its initial indication for the treatment of massiverotator cuff tears (MRCTs) with cuff tear arthropathy (CTA),its use rapidly extended to other pathologic shoulder con-ditions, including primary osteoarthritis (OA),47 tumors,11

proximal humeral fractures,48 and revision shoulder repla-cement.6 RSA has been shown to be effective in treatingshoulder pseudoparalysis, showing pain relief and mot-ion improvements with patient satisfaction after short-termfollow-up.1,10,47,49 Despite these encouraging results, fewstudies to date have performed a midterm or long-termsurvivorship analysis of RSA patients with CTA, MRCT,or primary OA,14,44 and even less is known about possiblepredictors of midterm or long-term outcomes of thisprocedure. Furthermore, data on patients’ quality of lifeafter RSA, as assessed by validated tools, are lacking.

The purpose of this study is to report the midtermsurvival rate, health-related quality of life (HRQoL), andfunctionality of the shoulder after RSA in a prospectiveseries of patients with MRCT, CTA, or primary gleno-humeral OA and identify the possible predictors of clinicaloutcomes.

Methods

Study population

The study protocol was approved by the local ethical committee,and the research was performed in compliance with the HelsinkiDeclaration. Inclusion criteria were (1) age greater than 18 yearsat operation and (2) primary RSA. Exclusion criteria were prox-imal humeral fractures and fracture sequelae, rheumatoid arthritis,tumors, evidence of an active infection, allergic reactions to metalimplants, alcohol abuse, a predicted survival of less than 6 months,a patient’s unwillingness to cooperate, and legal incapacitation.One hundred nine patients fulfilling the inclusion and exclusioncriteria were operated on at our institution between 2003 and2008. Of these, 5 (4.6%) refused to participate in the studybecause of a lack of interest or the inability to return for scheduledvisits. In addition, 15 patients (13.8%) were lost to follow-up, and9 patients (8.3%) died of unrelated causes. Data were available for80 patients (cases), who represented 80% of the survivors (TableI). At surgery, patients’ ages averaged 72.5 � 5.0 years (range,61-86 years), and patients had a diagnosis of either irreparableMRCT, CTA, or primary glenohumeral OA according to clinicaland radiographic features.23,37 The diagnostic criteria for anirreparable MRCT were grade 3 tendon retraction (based on theclassification system of Patte41) and/or grade 3 or 4 fatty infil-tration (based on the classification system of Goutallier et al19)shown on magnetic resonance images.15 All the patients gaveinformed consent for participation in the study, which was per-formed with prospective data collection.

Clinical evaluation

A complete clinical history was obtained from all patients.Baseline social, anthropometric, educational, and occupationalvariables that might be associated with the outcomes were gath-ered through a study-specific questionnaire. All the participants

then underwent a structured assessment using an expandedoutcome set based on previously published measures and defini-tions summarized in Table II. Information about comorbidity wasgathered in an interview with the patient using the CumulativeIllness Rating Scale (CIRS),29 and the severity index was calcu-lated as the sum score on the CIRS divided by the morbidity count(ie, the number of diseases).17 Before surgery and at the lastfollow-up available, a standardized examination of the shoulder’srange of motion (ROM) was conducted with the patient’s besteffort at active direct forward flexion, abduction, and external andinternal rotation. In detail, patients performed flexion andabduction while standing and actively moving each outstretchedarm simultaneously. Both external rotation and internal rotationwere performed while patients were seated with the elbows at theirsides in adduction.

The preoperative Constant-Murley score (CMS)9 and post-operative CMS were measured in all the patients, and a digitaldynamometer (Myometer 500 N; Atlantech Medical Devices,Nottingham, UK) was used for power evaluation. Patients wereconsidered a treatment success if their CMS at the study’sendpoint was at least 80% of the standard age- and sex-relatedvalue.16,26 An absolute CMS of 30 or less or a CMS for pain of10 or less at the final follow-up were considered poor clinicalresults.22 For both ROM and the CMS, the recovery rate (RR)

Table II Clinical and imaging assessment

Scale or finding Purpose Definitions and details

Clinical, demographic, and functional parametersCIRS Comorbidities Summative score for 13 independent organ area domains, each scored from 1 (none)

to 5 (extremely severe); the CIRS category ‘‘muscle, bone and skin diseases’’ wasexcluded from analysis

CMS Shoulder functionality Two objective scales: patient’s ROM (40 points) and power (25 points)Two subjective scales: pain (15 points) and impact on ADLs (20 points)

SF-36, Italian version General quality of life Eight scales: physical functioning, role-physical, bodily pain, general health, vitality,social functioning, role-emotional, and mental health

Two summary measures: physical component summary and mental componentsummary

Study-specific questionnaire Civil status Married or widowedEducational level Illiteracy, primary school, middle school, or high schoolEmployment Unemployed, employed, or retiredUse of painkillers No use, use for <4 d monthly, use for 4-10 d monthly, or use for >10 days monthly

Imaging assessmentHamada Radiographic classification Stage 1: minimal radiographic changes

Stage 2: narrowing of subacromial space �5 mmStage 3: erosion and acetabulization of acromion secondary to superior migration of

humeral headStage 4: glenohumeral arthritis without (4a) and with (4b) acetabulizationStage 5: humeral head osteonecrosis

Modified Gruen Humeral radiolucencies Zone 1: near greater tuberosityZone 2: near lateral metaphysisZone 3: near lateral diaphysisZone 4: at tip of humeral implantZone 5: near medial diaphysisZone 6: near medial metaphysis

Melis Glenoid radiolucencies Classification of any radiolucent lines around glenoid screws, around peg, or belowbaseplate based on their width (<2 mm or �2 mm)

Sirveaux Scapular notching Grade 1: defect contained within inferior pillar of scapular neckGrade 2: erosion of scapular neck to level of inferior fixation screw of glenosphere

baseplateGrade 3: erosion extended over fixation screwGrade 4: erosion progressed to undersurface of baseplate

HRQoLandfunctio

nality

afterRSA

1641

1642 R. Castricini et al.

was computed using the following formula: RR ¼ (Postoperativevalue � Preoperative value)/Postoperative value � 100. The po-stoperative assessment of patients included the official Italianversion of the Short Form Health Survey questionnaire (ShortForm 36 [SF-36]) to measure HRQoL,2 and standard recommen-dations for questionnaire administration were followed in thecollection of all data.3 As previously described,30,31 the SF-36results were compared with the published data.3 Patients obs-erved a pain medication–free interval 3 days before each evalua-tion. Intraoperative or postoperative complications were noted.

Imaging assessment

A radiologic assessment was performed preoperatively and post-operatively in 62 patients. The radiographic evaluation was basedon an axillary radiograph, 2 true anteroposterior views of theglenohumeral joint (ie, a 40� posterior oblique radiograph withexternal rotation of the humerus and a 40� posterior obliqueradiograph with internal rotation of the humerus), and a scapularlateral view of the shoulder. A trained musculoskeletal radiologistwho was unaware of the patients’ clinical features reviewed eachpatient’s radiographic studies. The preoperative MRCT and CTAradiographs were graded as previously described by Hamadaet al.23 Evidence of humeral radiolucencies was evaluated with thesystem described by Gruen et al21 adapted to the shoulder.32

Humeral loosening was defined as a radiolucent line of 2 mm orgreater in 3 or more contiguous zones.8 Radiolucencies around theglenoid component were evaluated according to Melis et al.32

Glenoid loosening was considered to be present when 2 mmlucent lines or a shift in position between postoperative andfollow-up radiographs was noted or when the component wasdisplaced.32 Periprosthetic calcifications were evaluated as previ-ously described.7 Radiographs were also evaluated for scapularnotching on the basis of the criteria of Sirveaux et al.43

Operative technique and postoperative protocol

All procedures were performed by 1 surgeon (R.C.) with thepatient under general anesthesia with an interscalene nerve blockin the beach-chair position. In brief, a deltopectoral approach wasadopted in all patients. The subscapularis tendon was sectioned atthe level of the anatomic neck of the humerus and, after implan-tation, was not repaired in any case. A Delta III implant (DePuy,Saint-Priest, France), which is based on the Grammont designwith a medialized center of rotation, was used in all patients. Thehumeral head was osteotomized in neutral retroversion. Thehumeral canal was then reamed, and a standard-length humeralstem was cemented. The cement (Palacos RþG; Heraeus GmbH,Wehrheim, Germany) was prepared with the use of a vacuummixing device (Palamix; Heraeus GmbH) following the instruc-tions of the manufacturer. Intramedullary plugs were used in allcases to increase the cement-bone interface pressure during theinsertion of the humeral component.

The glenoid baseplate was fixed into position with four 3.5-mmunlocking screws. A 36-mm glenosphere with a neutral offset wasplaced in all cases. A surgical drain was applied in all cases, andits use was discontinued after 24 hours. Postoperatively, patientsused a 15�-to-30� abduction shoulder immobilizer for 3 weeks andperformed pendulum exercises on a daily basis. Afterward, theimmobilizer was discontinued, passive and active-assisted ROM

exercises were begun, and patients were permitted to use theirextremities for activities of daily living (ADLs). After a 2-monthperiod, patients were allowed to begin strengthening the shoulder.

Statistical analysis

The mean, standard deviation, and range were reported for thecontinuous variables, whereas counts described the categoricalvariables. The Student t test was used to test the significance of thedifferences. Univariate linear and logistic analyses were first per-formed to select the variables to be included in the models ofa forward stepwise multiple regression analysis. Only explanatoryand confounding variables that showed a trend toward an associationwith the outcome of interest (ie, P � .1) in the univariate analysiswere inserted in these models. In the multiple linear regressionanalysis, total adjusted R2 for the model and changes in R2 for theindependent contribution of single predictors were calculated toassess the total variance in the outcome variable accounted for bythe whole model and the single explanatory variables, respectively.In the case of collinearity between the explanatory variables, onlythe best-fitting models (eg, those including the collinear explanatoryvariable accounting for the most relevant variation in the variance ofthe outcomes) were adopted. Explanatory and confounding variablesincluded in the analysis were age (continuous), sex (categorical),Hamada grade (discrete), civil status (categorical), educational level(discrete), employment (discrete), CIRS severity index (continuous),previous surgery (categorical), length of follow-up (continuous),preoperative flexion (continuous), preoperative abduction (contin-uous), preoperative external rotation (continuous), preoperativeinternal rotation (continuous), preoperative total CMS (continuous),preoperative pain CMS (continuous), preoperative ADL CMS(continuous), preoperative ROM CMS (continuous), and preopera-tive power CMS (continuous). Postoperative flexion (continuous),flexion RR (continuous), postoperative abduction (continuous),abduction RR (continuous), postoperative external rotation (contin-uous), external rotation RR (continuous), postoperative internalrotation (continuous), internal rotation RR (continuous), post-operative total CMS (continuous), total CMS RR (continuous),postoperative pain CMS (continuous), pain CMS RR (continuous),postoperative ADL CMS (continuous), ADL CMS RR (continuous),postoperative ROM CMS (continuous), ROM CMS RR (contin-uous), postoperative power CMS (continuous), power CMS RR(continuous), postoperative physical component summary (contin-uous), postoperative mental component summary (continuous),complications (categorical), calcifications (categorical), humeralradiolucencies (categorical), glenoid radiolucencies (categorical),scapular notching (discrete), and the use of painkillers (discrete)were treated as outcomes, and the effects of possible predictors werechecked for their values.

Survival curves were established with the Kaplan-Meiermethod.25 Failures were considered if at least 1 component ofthe prosthesis required exchange after the first operation. For thesurvival analysis, patients without failure were censored on thedate of the competing endpoint or study end date, whicheveroccurred first. The difference in cumulative survivorship accord-ing to etiology (ie, MRCT/CTA and primary glenohumeral OA)was assessed with the log-rank test.

To calculate the power (1 � b error probability; 2 tailed)achieved by our statistical tests, we considered the actual samplesize, observed effect size, and a value ¼ .05. GraphPad Prismsoftware (version 5.0; GraphPad, San Diego, CA, USA), SPSS

Table III Comparison between baseline and follow-up values

Preoperative Postoperative RR)

ROMFlexion 100� � 20� (50�-150�) 150� � 29� (70�-180�) 30.9%Abduction 81� � 19� (40�-120�) 133� � 35� (50�-180�) 44.4%External rotation 17� � 11� (0�-40�) 37� � 17� (0�-70�) 21.7%Internal rotation 47� � 14� (20�-70�) 64� � 14� (30�-80�) 34.9%

CMSTotal 23 � 7 (6-42) 66 � 11 (34-85) 64.2%Pain 2 � 3 (0-5) 14 � 2 (5-15) 83.1%ADLs 7 � 2 (4-12) 17 � 3 (10-20) 58.3%ROM 13 � 5 (2-24) 29 � 6 (12-40) 53.7%Power 1 � 1 (0-5) 6 � 3 (1-15) 79.7%

) RR ¼ (Postoperative value – Preoperative value)/Postoperative value � 100.

Table IV Mean CMSs in patients and sex- and age-matched population norms

Women Men

Patients Controls % Patients Controls %

Aged 60-69 y 67.1 70 96.0% 71.7 83 86.4%Aged �70 y 63.0 69 91.3% 74.5 75 99.3%

HRQoL and functionality after RSA 1643

software (version 17.0; SPSS, Chicago, IL, USA), and G*Powersoftware (version 3.1; Institut f€ur Experimentelle Psychologie,Heinrich Heine Universit€at, D€usseldorf, Germany) were used forthe database construction and the statistical analysis. P < .05 wasconsidered significant.

Results

Clinical and radiologic results

At the last follow-up (mean, 60 � 18 months; range, 36-99months), patients were aged 78 � 6 years (range, 67-91years). As shown in Table III, active ROM and CMSdomains showed an improvement from the preoperativeto postoperative evaluations (P < .001 for all). No patientswith a postoperative CMS of 30 or less were noted, and8 patients (10%) reported poor pain relief (ie, painCMS �10). Postoperative CMS was 93% of the sex- andage-matched normal values,26 with 63 of 80 treatmentshaving been successful. In detail, the CMS, stratified intosex- and age-matched groups, is reported in Table IVin comparison with the sex- and age-matched normativedata.26 The postoperative SF-36’s physical and mentalcomponent summary mean scores measured 44 � 10(range, 17-57) and 45 � 10 (range, 20-59), respectively.The subjects’ SF-36 scores, stratified into age groups, arereported in Table V and showed no significant differencesin comparison with the age-matched normative data.3

When patients were stratified according to etiology(ie, MRCT/CTA vs primary glenohumeral OA), both gr-oups improved with surgery (P < .001 for ROM and CMS

domains), and as shown in Table VI, no significant differ-ences were noted for either postoperative value. Similarly,no differences were found in the postoperative SF-36domains between the groups.

In 4 patients (5%), complications developed: dislocation(2), infection (1), and hematoma (1). The dislocationsoccurred in a 69-year-old man who underwent an RSA forCTA and in a woman aged 72 years with primary gleno-humeral OA; both patients underwent successful revisionwith a polyethylene exchange. A penicillin-susceptiblestreptococcal prosthetic joint infection occurred 20 daysafter surgery in a 78-year-old woman with primary gleno-humeral OA, and she was treated with intravenouslyadministered antimicrobial therapy, debridement, andretention of the prosthesis. A hematoma occurred 15 daysafter the RSA for primary glenohumeral OA in a womanaged 76 years, and it was drained with no need for removalof the implant.

Radiographs from 62 of 80 patients showed peri-prosthetic calcifications in 29 patients (47%) and 1-mmhumeral radiolucencies in 5 patients (8%). Radiolucencieswere noted in zone 1 (2), zone 6 (2), zone 4 (1), and zone7 (1) (1 of the patients showed radiolucencies simulta-neously in zones 1 and 6). Nine glenoid components (15%)exhibited incomplete radiolucencies of less than 2 mm thatextended around the baseplate and the inferior screw (5) orcentral peg (4). None of these radiolucencies were presenton the initial postoperative radiograph. Of 62 patients,44 (71%) had evidence of scapular notching: 31 casesshowed grade 1 notching, 10 had grade 2 notching, 2 hadgrade 3 notching, and 1 had grade 4 notching.

Table V SF-36 scores in patients and age-matched population norms

Age group 65-74 y Age group �75 y

Patients (n ¼ 25) Controls P value Patients (n ¼ 55) Controls P value

PF 69.2 � 25.5 (15-100) 67.3 � 26 .912 71.3 � 22.5 (15-95) 45.6 � 35.2 .101RP 52.1 � 50.5 (0-100) 60.0 � 40.4 .806 52.6 � 44.0 (0-100) 45.5 � 53.1 .802BP 57.5 � 29.6 (10-100) 62.8 � 29.1 .785 63.4 � 25.4 (22-100) 48.3 � 36.3 .373GH 61.7 � 19.4 (25-92) 51.6 � 21.5 .438 57.5 � 17.6 (25-87) 40.7 � 28.7 .172VT 60.0 � 25.3 (15-100) 55.0 � 21.1 .759 57.1 � 22.0 (15-100) 42.8 � 28.8 .287SF 62.5 � 19.2 (37.5-87.5) 72.9 � 24.9 .441 67.0 � 23.1 (25-100) 58.3 � 32.5 .572RE 75.0 � 38.0 (0-100) 70.5 � 36.8 .855 66.7 � 45.8 (0-100) 50.9 � 54.2 .592MH 60.0 � 19.0 (32-88) 60.4 � 21.0 .969 60.4 � 20.0 (24-96) 52.3 � 29.8 .546PCS 42.8 � 12.0 (12.7-56.6) 42.7 � 9.1 .989 44.1 � 8.6 (28.8-56.2) 35.8 � 10.7 .149MCS 45.7 � 8.3 (32.2-58.6) 45.8 � 8.7 .992 44.5 � 11.8 (20.4-58.8) 41.4 � 11.1 .645

BP, Bodily pain; GH, general health; MCS, mental component summary; MH, mental health; PCS, physical component summary; PF, physical functioning;

RE, role-emotional; RP, role-physical; SF, social functioning; VT, vitality.

Table VI Comparisons between postoperative clinical results based on diagnosis

MRCT and CTA OA P value

ROMFlexion 148� � 32� (70�-180�) 152� � 25� (95�-180�) .858Abduction 130� � 36� (50�-180�) 138� � 33� (70�-180�) .393External rotation 37� � 16� (0�-60�) 38� � 18� (10�-70�) .96Internal rotation 63� � 15� (30�-80�) 65� � 14� (40�-80�) .542

CMSTotal 66 � 11.7 (34-82) 67.0 � 10.5 (48-85) .891Pain 14.4 � 2.0 (5-15) 14.6 � 1.5 (10-15) .807ADLs 17.3 � 3.0 (10-20) 17.4 � 3.0 (12-20) .802ROM 28.6 � 6.7 (12-38) 29.4 � 5.5 (16-40) .867Power 5.8 � 3.2 (2-15) 5.5 � 3.3 (1-14) .686

SF-36PF 66.9 � 25.3 (15-95) 75.4 � 20.2 (40-100) .334RP 50.0 � 47.0 (0-100) 55.8 � 45.8 (0-100) .78BP 59.3 � 29.1 (10-100) 63.6 � 24.1 (32-100) .701GH 57.0 � 21.9 (25-92) 62.1 � 10.7 (45-77) .718VT 55.8 � 23.4 (15-100) 61.5 � 19.9 (15-100) .572SF 62.5 � 21.9 (25-100) 69.0 � 21.2 (25-100) .404RE 66.7 � 44.3 (0-100) 74.4 � 41.2 (0-100) .637MH 61.6 � 19.7 (24-96) 58.5 � 17.5 (32-96) .533PCS 42.1 � 10.7 (17.2-56.6) 45.7 � 8.6 (33.4-56.3) .347MCS 45.1 � 10.1 (25.7-58.6) 44.9 � 9.7 (20.4-58.8) .936

BP, Bodily pain; GH, general health; MCS, mental component summary; MH, mental health; PCS, physical component summary; PF, physical functioning;

RE, role-emotional; RP, role-physical; SF, social functioning; VT, vitality.

1644 R. Castricini et al.

Correlation and regression analysis

Models of univariate regression analysis showed that ayounger age predicts higher postoperative flexion (P ¼ .01,b ¼ �0.28), abduction (P ¼ .02, b ¼ �0.27), externalrotation (P ¼ .001, b ¼ �0.35), internal rotation (P ¼ .003,b ¼ �0.33), total CMS (P ¼ .04, b ¼ �0.23), and ADLCMS (P ¼ .01, b ¼ �0.30). Younger patients also exhibitedan inclination toward the development of radiolucent linesaround the humeral stem (P ¼ .003, b ¼ �0.37).

As shown in Table VII, age-weighted stepwiseregression models showed major determinants (ie, those

explaining a variation in the variance of the outcome ofthe model �3%) of postoperative outcomes. The base-line values of CMS domains were negatively associatedwith the respective RRs. The length of follow-upbehaved as a positive predictor of scapular notching,with an increase of severity over time, although thisexplanatory variable accounted for only a small amountof the variation in this index. Greater use of painkillerswas directly associated with previous shoulder surgery(ie, arthroscopic debridement in a 77-year-old womanand a 69-year-old man [who both had MRCT] and ina 64-year-old woman with primary OA, as well as

Table VII Major determinants of surgical outcomes based on age-weighted multiple linear regression analysis

Explanatory variables Surgical outcome b P value Total adjusted R2 R2 change

Preoperative total CMS Total CMS RR �0.769 <.001 0.707 66.6%Preoperative pain CMS Pain CMS RR �0.986 <.001 0.972 97.3%Preoperative ADL CMS ADL CMS RR �0.746 <.001 0.55 55.6%Preoperative ROM CMS ROM CMS RR �1.284 <.001 0.646 56.8%Preoperative power CMS Power CMS RR �0.7 <.001 0.483 49.0%Length of follow-up Scapular notching 0.315 .013 0.084 9.9%Previous surgery Use of painkillers 0.281 .012 0.067 7.9%

ROM, range of motion; CMS, Constant-Murley score; ADL, activities of daily living; RR, recovery rate ¼ (postoperative value – preoperative value)/

postoperative value � 100.

HRQoL and functionality after RSA 1645

lipoma excision from the deltoid region of a 73-year-oldman with MRCT).

Survival analysis

In 2 patients (3%), failure occurred because of prosthesisdislocations with a further implant exchange; with thisvalue as an endpoint, survivorship was 100% at 2 years,99% at 5 years, and 66% at the last follow-up available (ie,99 months), with a cumulative survival rate of 97% (Fig. 1).When the curves were segmented according to etiology,cumulative survivorship was 98% and 97% for the MRCT/CTA and OA patients, respectively (Fig. 2). No significantdifference was shown in terms of survival between the2 groups (hazard ratio, 0.1 [95% confidence interval,0.01-5.09]; P ¼ .248).

Figure 1 Kaplan-Meier curves of RSA survival rate in wholepopulation.

Discussion

Modern semiconstrained RSAs have shown a greatimprovement in function and ROM in a wide range ofclinical studies with different etiologies,38 including revi-sion surgery,10,49 sequelae of fractures,6 or tumors.47

However, as shown in Table VIII, few studies have evalu-ated the RSA for OA, CTA, or MRCT excluding any othershoulder disease. Further weaknesses that limit the possi-bility of drawing firm conclusions from these studies arethe involvement of multiple centers with many surgeonsperforming surgery, the retrospective design, and the lackof patient-based quality-of-life evaluations; in this study,we tried to overcome some of these limitations.

We showed that patients who had undergone an RSAa mean of 5 years earlier had a similar midterm HRQoLwith respect to age-matched healthy controls. Only 1 study,with a shorter follow-up of patients, used the SF-36 in theevaluation of RSA after CTA.36 The authors showed poorerresults in comparison with the average population but didnot report the preoperative and postoperative scores or theirimprovements after surgery. It is tempting to speculate thatthe high SF-36 scores we obtained are influenced by theinitial selection of patients. Indeed, it has been previously

shown that patients with CTA, MRCT, and OA have thebest final clinical and functional outcomes after RSA.47

Our ROM and CMS results are consistent with those ofprevious reports on RSA after a shorter6,10,34,43 or similar14

follow-up period. No significant correlations between theROM or CMS results and the length of follow-up wereobserved. This finding concurs with data previously re-ported by Sirveaux et al,43 who showed that the CMS wasnot significantly affected by the length of follow-up 44months after RSA for CTA. These combined observationssuggest that clinical results after RSA are stable over time,at least in the midterm, after which a decrease in functionalscores can be expected.14 We observed no significantdifferences in total CMS and its domains when the patientswere divided according to etiology, and this finding concurswith previous observations that patients with CTA, MRCT,and primary OA do not differ significantly from oneanother after RSA with respect to postoperative CMS.35,47

Caution should be exercised when one is interpretingthese results because we noted a low statistical power of thetests used to detect the possible differences. The observedcase number may be too small to detect real differences

Figure 2 Kaplan-Meier curves of RSA survival rate comparingMRCT/CTA and OA patients.

1646 R. Castricini et al.

between the values. A total sample size of 341 patients pergroup for a given power of 80% would be required on thebasis of the reported CMS values to compare the differentetiologies in a randomized controlled clinical trial, andperforming a similar study with this sample size is clearlychallenging.

The similar CMS results that were noted when thepatients were stratified based on etiology confirm that,along with the classical indication for MRCT/CTA,4 RSAmay be effectively used in patients with primary gleno-humeral OA.48 We acknowledge that patients with gleno-humeral OA are commonly scheduled to undergo anatomictotal shoulder arthroplasty (TSA). However, in our study,patients with primary glenohumeral OAwere aged 73 yearson average, and these data suggested that they be treatedwith RSA. Indeed, aging is a major risk factor for rotatorcuff tears,50 and treatment with anatomic TSA may becomplicated by secondary rotator cuff dysfunction. A16.8% incidence of cuff rupture has been noted afteranatomic TSA; cuff rupture is significantly associated withloosening of components,51 which has a recently reportedincidence of 32%.12

Interestingly, we compared CMS values after RSA withsex- and age-matched normal values,26 showing similarscores. In our regression models, the baseline values of theCMS domains were negatively associated with the respectiveRRs; thus, the worse the preoperative shoulder condition, thehigher the possibility of an improvement with surgery.Accordingly, patients with the highest ROM achieved littlebenefit in ROM and pain relief after RSA,45 and the CMSvalues had doubled after RSA in patients with shoulderpseudoparesis (ie, active flexion <90�).49 Our study alsoshowed that the improvements in both ROM and CMS arehigher in younger patients, and these data are in agreementwith previous observations of older patients showing lowerpostoperative CMS and ROM values after RSA.7,18

We showed a complication rate of 5%, which isnoticeably lower than the overall rate (24%) reported ina recent systematic review of 21 RSA cohort studies,52 andwe may explain this discrepancy by assuming that thedefinition of complications greatly differs among thestudies. A further possible explanation of the low rate ofcomplications that we observed may be that all the patientsin our study had primary arthroplasties and it is well knownthat the complication rate is higher after revision RSA incomparison with primary RSA.46

We detected 8% and 15% rates of humeral and glenoidradiolucencies, respectively, which are lower values thanthose reported by other authors with shorter13 or longer32

observation times. We failed to uncover significant corre-lations between the presence or severity of radiolucenciesand the clinical outcomes, which confirms a previousobservation that humeral radiolucencies do not significantlyaffect the postoperative CMS values.8 For the first time, weshowed that younger patients have an inclination toward thedevelopment of radiolucent lines around the humeral stem.We can hypothesize that younger patients, having betterfunctional outcomes, might overuse the shoulder. However,it should be noted that we could not show any relationshipbetween radiolucencies and component loosening becauseno loosening was reported in this series. This concurs withthe 97% survival rate that we determined when a compo-nent revision was considered as the endpoint. This value ishigher than the values reported in other studies aftera similar follow-up period.22,43 We detected no significantsurvival differences when the curve was segmented byetiology. Guery et al22 previously showed that the survivalrate for RSAs in shoulders without a diagnosis of CTA issignificantly lower than that in patients with CTA becauseof the rapid loosening exhibited by the former group ofpatients. However, they included individuals with rheuma-toid arthritis, fractures, or replacements of anatomic TSAsin the subgroup of patients who did not have CTA. Thus,any comparison with our findings is not possible because ofdifferent patient characteristics.

We detected a mean rate of scapular notching of 71%,similar to rates reported in studies with a shorter follow-upperiod6,43 but lower than rates reported after a similar44 orlonger32 observation time. It is tempting to speculate that thelower reported rate of notching is the result of the surgicalapproach that we used, combined with the caudal positioningof the glenosphere baseplate. Indeed, the deltopectoralapproach commonly yields a lower incidence of scapularnotching compared with the anterosuperior approach.32,39

Moreover, the craniocaudal positioning of the glenospherebaseplate has been described as the most important predictorof scapular notching after RSA.42 Our regression analysesshowed that the severity of scapular notching increased withthe length of follow-up, thus confirming previous find-ings.5,14,28 Melis et al32 described an association between thefrequency of scapular notching and both the age of thepatients and the length of follow-up. It should be considered

Table VIII Clinical studies evaluating RSA for either MRCT, CTA, or primary OA

Authors Design Patients FU(mo)

Diagnosis Implant Complicationrate

SF-36(PCS/MCS)

Preoperative/postoperative CMS

Preoperative/postoperativeflexion

Preoperative/postoperativeabduction

Preoperative/postoperative ER

Preoperative/postoperative IR

Leung et al.,27

2012P 32 36 CTA Varied 25% d d 66�/113� d 29�/33� L3/T12

Favard et al.,14

2011R 148 90 MRCT, CTA, OA Varied 22% d 24/62 NS/129� d NS/11� d

Jobin et al.,24

2012P 37 16 CTA Varied 4% d d 38�/144� d d L4/L3

Naveed et al.,36

2011NS 43 39 CTA Delta III 16% NS/NS 17/59 55�/105� NS/85� d d

Nolan et al.,40

2011R 67 24 CTA NS 23% d 28/62 61�/121� d 14�/15� d

Favard et al.,13

2006NS 129 50 CTA Varied 12% d 23/65 72�/135� d 8�/11� d

Mol�e et al.,33

2006NS 39 43 MRCT NS 17% d 28/63 80�/133� d 10�/13� d

Walch et al.,46

2006NS 19 37 OA Varied 10% d 24/65 87�/142� d 4�/18� 3�/5�

Sirveaux et al.,43

2004NS 80 44 CTA Delta III 15% d 23/66 73�/138� d 3�/11� d

Vanhove et al.,45

2004R 14 31 CTA Delta III 7% d NS/60 d d d d

Valenti et al.,44

2001NS 39 84 CTA Delta III 23% d 21/63 60�/120� d d d

Current study P 80 60 MRCT, CTA, OA Delta III 5% 44/45 23/66 100�/150� 81�/133� 17�/37� 47�/64�

ER, External rotation; FU, follow-up; IR, internal rotation; MCS, mental component summary; NS, not stated; P, prospective; PCS, physical component summary; R, retrospective.

HRQoLandfunctio

nality

afterRSA

1647

1648 R. Castricini et al.

that the effect of scapular notching on functional outcomesstill remains controversial39: we failed to find any significantcorrelation between scapular notching and the clinicalresults, thus confirming the previous findings.14

Certain weaknesses in our study design limit the con-clusions that can be drawn from our data. First, the lowstatistical power of the test used to compare clinical resultsbased on etiology might have obscured some significantdifferences. Moreover, caution should be exercised ininterpreting the radiographic results because only 62 of80 patients had postoperative follow-up radiographs ava-ilable for evaluation. Despite these limitations, this studyprovides useful information on the midterm follow-up ofpatients undergoing an RSA, with important methodologicstrengths: the prospective design; the strict exclusion cri-teria; the use of an integrated outcome assessment withreliable and valid measures, with numerical scores andregression analysis; the length of follow-up; and the ho-mogeneous characteristics of the sample population, with1 surgeon performing all the operations according to thesame operative and postoperative protocol.

Conclusions

RSA allows for CMS and HRQoL results comparable tothe values of the normal population with a lowcomplication rate at midterm follow-up. Youngerpatients and subjects with worse preoperative conditionsachieved the greatest benefit after surgery, independentlyfrom the etiology. Long-term studies should be per-formed to confirm that these successful results aremaintained over time.

Disclaimer

The authors, their immediate families, and any researchfoundations with which they are affiliated have notreceived any financial payments or other benefits fromany commercial entity related to the subject of this article.

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