Glenoid lateralization and subscapularis repair are independent predictive factors of improved internal rotation after reverse shoulder arthroplasty.

PURPOSE: Reverse shoulder arthroplasty (RSA) has shown improvement in clinical outcomes for various conditions, although some authors expressed concern about the restoration of active internal rotation (AIR). The current study assesses preoperative and intraoperative predictive factors of AIR in patients having a Grammont-style RSA with a minimum five year follow-up. METHODS: We conducted a retrospective multicentric study, including patients operated on with a 155° Grammont-style RSA for cuff-related pathology or primary osteoarthritis with posterior subluxation or an associated cuff tear. Patients were clinically evaluated at a minimum of five year follow-up. Patients with previous surgery or those who had a tendon transfer with the RSA were excluded. Demographic parameters, BMI, preoperative notes, and operative reports were obtained from medical records. AIR was graded according to the constant score system from 0 to 10. RESULTS: A total of 280 shoulders in 269 patients (mean age at surgery, 74.9 ± 5.9 years) met the inclusion criteria and were analyzed. The average follow-up was 8.1 years (range, 5-16 years). Overall, AIR increased from 4.2 (SD 2.5, range 0 to 10) preoperatively to 5.9 (SD 2.6, range 0 to 10) at final follow-up. At the last follow-up, AIR increased in 56% of cases, was unchanged in 26% and decreased in 18%. In 188 shoulders (67%), internal rotation was functional and allowed patients to reach the level of L3 or higher. Multivariable linear regression found the following preoperative clinical factors predictive of worse AIR after RSA: male gender (ß = -1.25 [-2.10; -0.40]; p = 0.0042) and higher values of BMI (ß = -0.085 [-0.17; -0.0065]; p = 0.048). Two surgical factors were associated with better AIR after RSA: glenoid lateralization with BIO-RSA technique (ß = 0.80 [0.043; 1.56]; p = 0.039) and subscapularis repair (ß = 1.16 [0.29; 2.02]; p = 0.0092). CONCLUSIONS: With a mean of eight year follow-up (5 to 16 years), internal rotation was functional (≥ L3 level) in 67% of operated shoulders after Grammont-style RSA; however, two patients out of ten had decreased AIR after surgery. Male patients and those with higher BMIs had worse AIR, with glenoid lateralization (using the BIO-RSA technique) and subscapularis repair, as they are predictive of increased AIR after RSA. LEVEL OF EVIDENCE: Case series, Level IV.

Reverse shoulder arthroplasty in rheumatoid arthritis: survival and outcomes.

BACKGROUND: Despite its potential biomechanical advantages, reverse shoulder arthroplasty (RSA) is still considered to be particularly high risk in rheumatoid patients who are osteoporotic and immunodeficient. Our purpose was to report prosthesis survival, complications, and outcomes of RSA in patients with rheumatoid arthritis (RA) at minimum 5-year follow-up. METHODS: We conducted a retrospective multicenter study including 65 consecutive primary RSAs performed in 59 patients with RA between 1991 and 2010. We excluded rheumatoid patients with previous failed anatomic shoulder arthroplasty. Age at surgery averaged 69 years (range, 46-86 years). A structural bone grafting was performed in 18 cases (45%), using the humeral head in 15 cases (BIO-RSA technique), the iliac crest in 2 cases (Norris technique), and an allograft in 1 case. The mean follow-up was 92 months (range, 60-147 months) or until revision surgery. RESULTS: Revision-free survivorship, using Kaplan-Meier curves, was 96% at 7 years. Two patients had revision surgeries for infections, with associated glenoid loosening in 1 case. No humeral loosening was recorded. The mean adjusted Constant score improved from 36% ± 23% preoperatively to 90% ± 26% postoperatively, and mean Subjective Shoulder Value improved from 21% ± 13% to 85% ± 12%, respectively (P < .001). Active anterior elevation increased from 65° ± 43° to 132° ± 27°, active external rotation increased from 10° ± 26° to 22° ± 27°, and internal rotation improved from buttocks to waist (P < .001). Stable fixation of the baseplate was achieved in all cases (including the 6 patients with end-stage RA), and we did not observe bone graft nonunion or resorption. Preoperative radiologic pattern (centered, ascending, or destructive), presence of acromial fractures or tilt (4 cases, 10%), and scapular notching (55%) on final radiographs were not found to influence outcomes or complication rate. Patients with absent/atrophied teres minor had lower functional results. Overall, 95% of the patients were satisfied with the procedure. CONCLUSION: RSA is a safe and effective procedure for the treatment of RA patients, with a low risk of complications and low rate of revision, regardless of the radiologic presentation and stage of the disease. Rheumatoid patients undergoing primary RSA, with or without glenoid bone grafting, can expect a revision-free survival rate of 96% at 7-year follow-up. RSA offers the benefit of solving 2 key problems encountered in rheumatoid shoulders: glenoid bone destruction and rotator cuff deficiency.

Pyrocarbon interposition shoulder arthroplasty: preliminary results from a prospective multicenter study at 2 years of follow-up.

BACKGROUND: The concept of free interposition arthroplasty proved successful for small joints of the hand, wrist, and foot, particularly after the use of implants coated with pyrocarbon, which enhanced their tribologic and elastic properties. The present study reports preliminary outcomes of a pyrocarbon-coated interposition shoulder arthroplasty (PISA) implant. METHODS: This was a prospective study of 67 consecutive patients who underwent shoulder PISA at 9 centers. The mean age at surgery was 51 years, with only 12 patients older than 60 years. The indications for surgery were primary glenohumeral arthritis in 42, avascular necrosis in 13, and secondary arthritis in 12 patients. RESULTS: Revision surgery was performed in 7 patients (10.4%), 2 (3.0%) were lost to follow-up, and the outcome assessments were incomplete in 3 (4.4%). This left 55 patients, aged 49.3 ± 12.0 years, with complete outcomes assessments at a mean follow-up of 26.8 ± 3.4 months. The Constant score improved from 34.1 ± 15.1 preoperatively to 66.1 ± 19.7 postoperatively. The radiographic findings revealed erosion in 6 glenoids and thinning of 3 humeral tuberosities. CONCLUSION: In a cohort of young arthritic patients, PISA renders clinical scores and implant survival comparable to those of hemishoulder arthroplasty but remain inferior to those results reported for total shoulder arthroplasty. The study enabled identification of contraindications and potential causes of failure that wererelated to the concept of free interposition and smaller radius of curvature of the sphere. Until long-term results are available, this type of innovative implant should remain to be tested in a few specialized shoulder centers.

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.

Surgical technique arthroscopic posterior glenoidplasty for posterosuperior glenoid impingement in throwing athletes.

BACKGROUND: Posterosuperior glenoid impingement (PSGI) is the repetitive impaction of the supraspinatus tendon insertion on the posterosuperior glenoid rim in abduction and external rotation. While we presume the pain is mainly caused by mechanical impingement, this explanation is controversial. If nonoperative treatment fails, arthroscopic débridement of tendinous and labral lesions has been proposed but reportedly does not allow a high rate of return to sports. In 1996, we proposed adding abrasion of the bony posterior rim, or glenoidplasty. DESCRIPTION OF TECHNIQUE: After arthroscopic assessment of internal impingement in abduction-extension-external rotation, extensive posterior labral and partial tendinous tear débridement is performed. Glenoidplasty involves recognition of a posterior glenoid spur and when present subsequent abrasion with a motorized burr. METHODS: We retrospectively reviewed 27 throwing athletes treated between 1996 and 2008. Age averaged 27 years. CT arthrogram showed bony changes on the posterior glenoid rim in 21 shoulders. We evaluated 26 of the 27 patients at a minimum followup of 19 months (mean, 47 months; range, 19-123 months). RESULTS: Eighteen of the 26 patients resumed their former sport level. Six improved but had to change to an inferior sport level or another sport. Two patients did not improve after the procedure, one of whom changed sport practice. There were no complications or posterior instability. In the 15 patients who had radiographs at followup times from 20 to 87 months, we observed no arthritis or osteophyte. CONCLUSIONS: Comparison with an earlier series of soft tissue débridement shows glenoidplasty improves the likelihood of resuming a former sport level in patients with PSGI. LEVEL OF EVIDENCE: Level IV, therapeutic study. See Guidelines for Authors for a complete description of levels of evidence.

Glenoid loosening and failure in anatomical total shoulder arthroplasty: is revision with a reverse shoulder arthroplasty a reliable option?

INTRODUCTION: Our purpose was to evaluate if, in case of aseptic glenoid loosening and failure in anatomical total shoulder arthroplasty (TSA), revision by a reverse shoulder arthroplasty (RSA) is a reliable therapeutic option. METHODS: Retrospective multicenter cohort study of 37 consecutive anatomical TSA revised by RSA for aseptic glenoid loosening or failure. The decision to implant a RSA was related to the presence of associated complications: rotator cuff tears (n = 24), subscapularis insufficiency (n = 29), prosthetic instability (n = 13), and glenoid bone deficiency (n = 37). The patients were reviewed clinically and radiographically at a mean follow-up of 47 months (range, 24-104). RESULTS: Eighty-six percent of the patients were satisfied or very satisfied. The average Constant score increased from 24 to 55 pts (P < .0001) and active anterior elevation from 68° to 121° (P < .0001). Twenty-two of the 29 (76%) associated bone grafts were incorporated in the glenoid. Eight patients (21%) needed a subsequent reoperation because of recurrent or new complications: glenoid loosening (n = 3), prosthetic anterior instability (n = 3), and humeral subsidence (n = 2); the reverse prosthesis had to be converted to a hemiarthroplasty in 1 patient and removed in another. CONCLUSION: Revision with a RSA is a reliable therapeutic option which provides the double benefit of glenoid bone stock reconstruction by fixing the bone graft with the help of the baseplate and screws and of solving the problem of soft tissue insufficiency and prosthetic instability. However, surgeons should be aware that the rate of postoperative complications and subsequent reoperations is high, and that the surgical technique is demanding.

Midterm results of pyrocarbon interposition shoulder arthroplasty: good outcomes after posttraumatic osteonecrosis without malunion of the tuberosities.

Background: In vitro data demonstrate the potential benefits of the pyrocarbon as a bearing material against cartilage or bone. And pyrocarbon-free interposition arthroplasty has been used with positive outcomes for over 10 years for hand and wrist joint replacements. This study reports the midterm results of a Pyrocarbon Interposition Shoulder Arthroplasty (PISA) in primary and secondary glenohumeral osteoarthritis and in avascular osteonecrosis. Methods: This prospective noncontrolled, multicenter study included 67 consecutive patients who underwent PISA in France and Sweden. Results: A cohort of 48 patients, aged 50 ± 12 years, was available for clinical assessment at a mean follow-up of 67.6 ± 9.3 months. A favorable change was reported with a mean absolute Constant score improvement of 32 ± 20 points. The highest Constant score improvement was observed in patients with avascular osteonecrosis (42 ± 18 points; P ≤ .0001). Between the earliest and the latest follow-up, radiographic analyses revealed only 2 major glenoid erosions and 4 tuberosity thinnings and thus that 86.4% of 44 shoulders remained stable with no or minor radiologic evolutions. The survival rate was 84 % at 65 months of follow-up considering all causes of revision. Conclusion: The radiographic findings seem to confirm the interest of pyrocarbon in preserving bony surfaces. But the risk of tuberosity thinning suggests considering the use of PISA with caution in most degenerative glenohumeral joint pathologies, although the midterm outcomes highlight PISA as a suitable solution for patients presenting with posttraumatic osteonecrosis without malunion of the tuberosities and with an intact rotator cuff.

Reverse prostheses in arthropathies with cuff tear: are survivorship and function maintained over time?

BACKGROUND: The use of reverse shoulder arthroplasty has considerably increased since first introduced in 1985. Despite demonstrating early improvement of function and pain, there is limited information regarding the durability and longer-term outcomes of this prosthesis. QUESTIONS/PURPOSES: We determined complication rates, functional scores over time, survivorship, and whether radiographs would develop signs of loosening. PATIENTS AND METHODS: We retrospectively reviewed 527 reverse shoulder arthroplasties performed in 506 patients between 1985 and 2003. Clinical and radiographic assessment was performed in 464 patients with a minimum followup of 2 years and 148 patients with a minimum followup of 5 years (mean, 7.5 years; range, 5-17 years). Cumulative survival curves were established with end points being prosthesis revision and Constant-Murley score of less than 30 points. RESULTS: Eighty-nine of 489 had at least one complication for a total of 107 complications. Survivorship free of revision was 89% at 10 years with a marked break occurring at 2 and 9 years. Survivorship to a Constant-Murley score of less than 30 was 72% at 10 years with a marked break observed at 8 years. We observed progressive radiographic changes after 5 years and an increasing frequency of large notches with long-term followup. CONCLUSIONS: Although the need for revision of reverse shoulder arthroplasty was relatively low at 10 years, Constant-Murley score and radiographic changes deteriorated with time. These findings are concerning regarding the longevity of the reverse shoulder arthroplasty, and therefore caution must be exercised when recommending reverse shoulder arthroplasty, especially in younger patients. LEVEL OF EVIDENCE: Level IV, therapeutic study. See Guidelines for Authors for a complete description of levels of evidence.

Scapular notching in reverse shoulder arthroplasty: is it important to avoid it and how?

BACKGROUND: Scapular notching, erosion of the scapular neck related to impingement by the medial rim of the humeral cup during adduction, is a radiographic sign specific to reverse shoulder arthroplasty (RSA). Its clinical and radiological consequences remain unclear. QUESTIONS/PURPOSES: Therefore, we: (1) determined the incidence of notching in a large series, (2) described the natural history of notching, (3) determined whether notching is related to functional scores or (4) radiographic signs of failure, and (5) identified factors related to notch development. PATIENTS AND METHODS: We retrospectively reviewed 448 patients who underwent a Grammont-type RSA (461 shoulders) with a mean followup of 51 months (range, 24-206 months). RSA was implanted for cuff tear arthropathy or osteoarthritis with cuff deficiency. We assessed scapular notching using AP views standardized under fluoroscopy. Clinical assessment included Constant-Murley score and range of motion. Aside from notching, radiographic assessment included evaluation of humeral and glenoid radiolucent lines. RESULTS: Notching occurred in 68% of cases. It appeared early, but its later evolution was variable. Notching was associated with followup, strength, passive and active elevation, humeral radiolucent lines, and glenoid lucent lines. It also correlated with a higher rate in patients with preoperative superior erosion. CONCLUSIONS: Scapular notching is frequent, generally progresses, and is associated with deterioration of some clinical parameters and radiolucent lines. We believe the preoperative pattern of glenoid erosion is of particular importance due to its influence on the surgeon's glenoid preparation and base-plate positioning. It is crucial to avoid cranial position and superior tilt. LEVELS OF EVIDENCE: Level IV, Therapeutic study. See Guidelines for Authors for a complete description of levels of evidence.

Clinical and Radiological Results of Hemiarthroplasty and Total Shoulder Arthroplasty for Primary Avascular Necrosis of the Humeral Head in Patients Less Than 60 Years Old.

BACKGROUND: Total shoulder arthroplasty (TSA) and hemiarthroplasty (HA) have shown good clinical outcomes in primary avascular necrosis of the humeral head (PANHH) both in short and long terms. The purpose of this study was to assess the complications, the clinical and radiological outcomes of shoulder arthroplasty in young patients with PANHH. METHODS: One hundred and twenty-seven patients aged under 60 years old and suffering from PANHH were operated with arthroplasty. Patients were assessed clinically and radiographically before surgery with a minimum of 2 years of follow up (FU). RESULTS: HA was performed on 108 patients (85%). Two patients were revised for painful glenoid wear after 2 and 4 years. TSA was performed on 19 patients (15%). Five TSA had to be revised for glenoid loosening (n = 4) or instability (n = 1). Revision rate was 26% with TSA and 2% with HA. There were no significant differences between HA and TSA in terms of clinical outcomes. CONCLUSIONS: With a mean FU of 8 years, HA and TSA improved clinical outcomes of patients with PANHH. HA revisions for painful glenoid wear were rare (2%). The revision rate was excessively high with TSA (26%).

Internal impingement of the shoulder: An international survey of 261 orthopaedic surgeons.

BACKGROUND: Internal impingement of the shoulder (IIS) is a specific disorder of young overhead-throwing athletes that was first described in 1991. The many non-operative and surgical treatments suggested to date have produced mixed outcomes. The objective of this study was to compare the practices of surgeons in France versus other countries regarding the diagnosis and treatment of IIS. HYPOTHESIS: Diagnostic and therapeutic practices regarding IIS differ between surgeons in France and in other countries. MATERIAL AND METHODS: A 21-item questionnaire in French and English was emailed to the 1300 members of the French Arthroscopy Society and to surgeons from countries other than France. The questionnaire collected information on knowledge about IIS (2 items), the frequency of IIS in clinical practice (2 items), the diagnosis of IIS (6 items), the non-operative and surgical treatment of IIS (3 and 5 items, respectively), and return-to-sports rates after treatment for IIS (3 items). RESULTS: The completed questionnaire was sent back by 261 surgeons, 206 in France and 55 in other countries, including 42 in Japan. Among the respondents, 90% knew about IIS. Experience with IIS in terms of number of patients seen or surgical treatments performed was greater in the international group (45% vs. 19% in France, p<0.001). Posterior shoulder pain in the arm cocking position was the most widely recognised symptom (99% in France, 74% internationally, p<0.001), followed by excessive external rotation during arm abduction (55% vs. 65%, p=0.23). The most commonly sought lesions were those of the postero-superior labrum and articular surface of the rotator cuff. Rotator cuff debridement was among the surgical options according to most respondents (74% vs. 70%). In contrast, postero-superior glenoidplasty was cited almost only by surgeons in France (67% vs. 4%, p<0.001). The proportion of patients who are able to return to sports was estimated at 50% to 75% by most respondents. DISCUSSION: Most respondents had theoretical knowledge about IIS, but surgery was rarely performed in France. Only very few athletes in France play baseball, which is responsible for most sports injuries of the shoulder seen in Japan. This fact, combined with differences in the lesions or even the diagnoses, may have contributed to the differences in the responses to the survey items between the French and international groups.

Internal impingement of the shoulder in overhead athletes: Retrospective multicentre study in 135 arthroscopically-treated patients.

BACKGROUND: Internal impingement of the shoulder (IIS) is the leading cause of chronic shoulder pain in overhead throwing athletes. No consensus exists about which techniques are optimal when surgery is in order. The available studies are limited by small sample sizes and short follow-ups. The primary objective of this study was to assess return-to-sports (RtS) outcomes after surgical treatment for IIS. A favourable RtS outcome (RtS+) was defined as returning to the previous sport at the same or a higher level. HYPOTHESIS: The main hypothesis was that surgical treatment resulted in an RtS+ outcome. The secondary hypothesis was that epidemiological factors, pre- and intra-operative anatomical factors, and specific surgical procedures were associated with higher RtS+ rates. MATERIAL AND METHODS: A retrospective multicentre design was used. We included 135 patients with IIS managed arthroscopically using any of the following procedures: anterior capsulorrhaphy, posterior capsulotomy/capsulectomy, postero-superior labral debridement, posterior glenoidplasty, and rotator cuff tear debridement or repair. Follow-up was at least 1 year. The patients were divided into two groups based on whether they had an RtS+ outcome as defined above or an RtS- outcome defined as a return to the previous sport at a lower level, a switch to another sport, or an inability to engage in any sport. The Kerlan-Jobe Orthopaedic Clinic (KJOC) and Constant's score were used to evaluate subjective and objective shoulder function. RESULTS: Mean follow-up was 7.9 years. Of the 135 patients, 120 (90%) returned to sports after surgery including 70 (52%) to the previous sport at the same level (RtS+ outcome). By univariate analysis, the following factors were associated with an RtS+ outcome: male sex, rotator cuff tear documented intra-operatively, absence of a greater tuberosity cyst on pre-operative imaging studies, and cuff tear debridement. Anterior capsulorrhaphy was associated with worse post-operative pain. DISCUSSION: The RtS+ rate in this study differed from previously reported values, due to differences in the sports practiced by the patients and to considerable variability in the surgical techniques used. The positive association between presence of a rotator cuff tear and an RtS+ outcome is at variance with most of the previously published data. Some of the apparent discrepancies between our results and those from other countries may be ascribable to differences in the most popular sports. LEVEL OF EVIDENCE: IV.

Is posterosuperior contact a normal occurrence in the shoulder?

Posterosuperior (or internal) impingement at the shoulder is defined as contact between the underside of the supraspinatus or infraspinatus tendons with the posterosuperior labrum during extreme external rotation and abduction. In many cases, this contact damages the tendon and causes mirror posterosuperior labrum deterioration. The primary aim of this study was to define whether this contact occurs normally in patients who do not have a rotator cuff tear. METHODS: We evaluated 100 shoulders in 100 patients. All patients were operated on in the beach chair position. After introducing the scope through the posterior portal, contact between the articular side of the rotator cuff and the posterosuperior labrum was noted as being present or absent when the arm was cocked in 90° abduction and 90° external rotation (90/90) then the arm was cocked in 140° abduction and maximum external rotation (140/Max). RESULTS: Contact was observed in 69% of patients in the 90/90 cocked position and in 94% of patients in the 140/Max cocked position. We found a correlation between the presence of rotator cuff and/or labrum lesions and the patient regularly performing arm-cock movements (p=0.035). DISCUSSION: Contact between the underside of the supraspinatus tendon and the posterosuperior labrum occurs physiologically. Repetitive arm-cock movements may contribute to macroscopic lesions of the underside of the rotator cuff and posterosuperior labrum. LEVEL OF EVIDENCE: IV, basic science study.

Scapular notching in reverse shoulder arthroplasty.

The causes and consequences of scapular notching after reverse shoulder arthroplasty (RSA) were investigated in 326 consecutive patients (337 shoulders) undergoing RSA between 1991 and 2003. Patients underwent 269 (80%) primary RSAs and 68 revisions of unconstrained shoulder prosthesis. At last follow-up (average, 47 months; range, 24-120 months) 62% had scapular notching. Notching frequency and extension were correlated to the length of follow-up (P = .0005). Notching was more frequent in cuff tear arthropathy (P = .0004), grade 3 or 4 fatty infiltration of the infraspinatus (P = .01), and narrowed acromiohumeral distance (P < .0001). Glenoids preoperatively oriented superiorly were more at risk for notching (P = .006). More notching occurred when the RSA was implanted using an anterosuperior approach vs a deltopectoral approach (P < .0001). Notching was correlated with humeral radiolucencies in proximal zones (P < .0001) and with glenoid radiolucent lines (P < .0001). Positioning of the baseplate definitely influences scapular notching. High positioning of the baseplate and superior tilting must be avoided.

Prosthetic replacement in the treatment of osteoarthritis of the shoulder: early results of 268 cases.

Two hundred sixty-eight anatomically designed shoulder arthroplasties for primary osteoarthritis were reviewed at a mean follow-up of 30 months. The Constant score adjusted for age and sex was 38% preoperatively and 97% at follow-up. Good or excellent results were observed in 77% of patients, and 94% were satisfied or very satisfied. Mean active forward elevation was 145 degree postoperatively, and all clinical parameters improved. Glenoid radiolucent lines were present in 58% of cases and were associated with a less satisfactory objective result. Postoperative active forward elevation, strength, and Constant score were inversely related to a tear of the supraspinatus or fatty degeneration of the infraspinatus. Patients who underwent biceps tenodesis had better pain relief. Complications occurred in 8.6% of cases, and 4.9% of shoulders required reoperation. Good early results can be obtained with nonconstrained shoulder arthroplasty in primary osteoarthritis.