Primary Glenohumeral Osteoarthritis Research Articles

Glenohumeral osteoarthritis: frequency of underlying diagnoses and the role of arm dominance-a retrospective analysis in a community-based musculoskeletal practice.

Patients with shoulder pain are commonly seen in adult primary care, and are typically referred to musculoskeletal specialists when their symptoms are persistent. Rotator cuff disorders (RCD) most commonly underlie non-traumatic shoulder pain in adults, and glenohumeral osteoarthritis (GHOA) has been considered to be relatively uncommon (Nakagawa et al., J Shoulder Elb Surg 8:580-584, 1999). Our impression has been that GHOA affects significant numbers of patients, is less well studied, and may be under recognized. Among adults referred to a musculoskeletal practice for shoulder pain evaluation, wedetermined the relative numbers of patients with a clinical diagnosis of RCD and GHOA by age and by gender, assessed the role of handedness in GHOA, and the proportion of patients with underlying conditions (versus primary or idiopathic GHOA). We also assessed the frequency of progression to operative management over a defined time interval. This is a retrospective case series of patients presenting to a musculoskeletal referral practice for shoulder pain. Patients with a clinical diagnosis of GHOA were identified with electronic medical records, and then assessed for demographic data, physical measures, comorbidities, and progression to surgical intervention within 2years. Among non-traumatic shoulder pain patients presenting to our practice during a 9-month period in 2013, RCD was diagnosed in 984 patients, and GHOA was diagnosed in 209 patients. 152 of the GHOA patients (73%) had primary (idiopathic) GHOA, without associated inflammatory conditions or cuff arthropathy. Primary GHOA affected the dominant arm in 38.7%, the non-dominant arm in 33.8%, and was bilateral in 27.5%. Patients diagnosed with primary GHOA were older than those with RCD (69.8 ± 12.2 vs 57.1 ± 15.1; p = 0.0001). Women represented 54% of cases of primary GHOA, and their presentation age was older than men (72.9 ± 11.2 vs 66.1 ± 12.4; p = 0.0005). Primary GHOA patients had a mean BMI of 31.0 ± 6.3, 48.7% had hyperlipidemia and 57.2% had hypertension. 24.3% were treated surgically within 2years of follow-up. GHOA is a significant cause of shoulder pain in older age groups, and the majority of these patients have primary (idiopathic) GHOA. Primary GHOA affects dominant and non-dominant arms at similar rates, suggesting that anatomical and/or systemic factors are more important than overuse in GHOA pathogenesis. Given the prominence of GHOA in older age groups, changes in population demographics, and limitations of non-operative treatment, continued increases in shoulder replacement surgery are likely. Efforts to further understand GHOA pathogenesis and develop new, more effective therapies are advocated.

Progression of Glenoid Morphology in Glenohumeral Osteoarthritis.

Walch defined the pathologic characteristics of glenohumeral osteoarthritis on the basis of patterns of glenoid morphology and humeral head subluxation. However, it is unclear how pathologic changes evolve over time. The purpose of this study was to determine whether there are common patterns of pathologic progression based on the Walch classification in primary glenohumeral osteoarthritis and if glenoid bone-loss patterns correlate with rotator cuff fatty infiltration. A retrospective chart review identified 65 shoulders with glenohumeral osteoarthritis for which at least 2 computed tomography (CT) scans had been performed at least 24 months apart. The CT scans were classified using a modification of the Walch classification. The amount and location of glenoid bone loss were measured using a vault model, and rotator cuff fatty infiltration was calculated as a percentage of cross-sectional muscle area. The initial CT scans showed 42 A-type glenoids and 23 B-type glenoids. CT scans made at an average (and standard deviation) of 74 ± 32 months after the initial scans showed that only 8 of the 42 A1 glenoids had evidence of pathologic progression (5 to A2 type and 3 to B type) whereas 17 of 19 B1 glenoids had progressed (15 to B2 and 2 to B3); this difference was significant on univariate and multivariate analysis (p < 0.001). The odds of joint line medialization occurring were 8.1 times higher (95% confidence interval [CI]: 2.1 to 31.4) for B-type glenoids than for A-type glenoids. Among the glenoids that underwent medialization, those classified as B-type showed more medialization over time (estimated change, 0.70 mm/year; p = 0.036), whereas no significant relationship between medialization and time was observed for A-type glenoids (estimated change, 0.013 mm/year; p = 0.95). The median percent fatty infiltration in the infraspinatus muscle was higher in association with B-type glenoids than in association with A-type glenoids on both the initial (14% versus 7%; p < 0.001) and the final follow-up (16% versus 10%; p = 0.003) CT scans. Asymmetric bone loss rarely develops in A1 glenoids, whereas initial posterior translation of the humeral head (B1 glenoids) may be associated with subsequent development and progression of posterior glenoid bone loss over time. Differences in fatty infiltration of the posterior aspect of the rotator cuff were seen between A-type and B-type glenoids, but the clinical relevance of this finding is currently unknown. Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

"Shaped" humeral head autograft reverse shoulder arthroplasty : Treatment for primary glenohumeral osteoarthritis with significant posterior glenoid bone loss (B2, B3, and Ctype).

Posterior glenoid bone loss in primary glenohumeral osteoarthritis (GHOA) presents achallenge when considering replacement surgery. Results with anatomic shoulder arthroplasty are unpredictable due to posterior humeral instability and limited bone stock for glenoid component fixation. To describe and evaluate the results of a"shaped" humeral head autograft with reverse shoulder arthroplasty (RSA) for the treatment of primary GHOA with significant posterior glenoid bone loss and an intact, functional rotator cuff. We retrospectively reviewed 29 "shaped" humeral head autografts with RSA for the treatment of GHOA with B2 (n= 16), B3 (n= 10), or C (n= 3) glenoid morphology based on the Walch classification system. Average glenoid retroversion was 32.3°. Humeral head autografts were "shaped" to match each patient's individual glenoid morphology. Functional outcome scores, range of motion, strength, and radiographic outcomes were evaluated. At average follow-up of 34.6months (range 23.7-88.9months), significant improvements were seen in all functional outcome scores, ranges of motion, and strength (p<0.01). No recurrent instability or glenoid fixation failure occurred. Two complications (1superficial and 1deep infection) in 2patients were identified. All autografts incorporated without radiographic evidence of loosening. Scapular notching was observed in 8shoulders. No negative correlations were identified with glenoid morphology. "Shaped" humeral head autograft with RSA for the treatment of primary GHOA with significant posterior glenoid bone loss is associated with excellent clinical and radiographic outcomes and alow complication profile at short- to mid-term follow-up.

Anatomic humeral head replacement with a press-fit prosthesis: An in vivo radiographic study.

Successful total shoulder arthroplasty is, in part, dependent on anatomic reconstruction of the glenohumeral joint. The purpose of this study was to evaluate the post-operative anatomy of total shoulder arthroplasty with an anatomic implant design in patients with primary glenohumeral osteoarthritis and compare it to published normative anatomic measurements. Fifty-one patients (56 shoulders) with primary glenohumeral osteoarthritis were treated with a press-fit humeral component as part of a total shoulder arthroplasty (Aequalis, Tornier, Edina, Minnesota). Analysis of postoperative true anterior posterior radiographs was performed with use of a custom software algorithm. The mean humeral inclination (head-shaft angle), mean humeral implant anatomical humeral axis, mean greater tuberosity height, and mean humeral head center offset (medial offset) were 135.4±5.1°, 1.73±1.7°, 6.9±2.4 mm, and 3.8±1.8 mm, respectively. All parameters were within the ranges reported in the literature for normal shoulders except the mean humeral head center offset, which was less than reported in the literature. Anatomic parameters of a total shoulder arthroplasty can be achieved with an anatomically designed, modular adaptable press-fit design. Reduced medial humeral head center offset was likely dependent upon implant specific design parameters.

Radiographic and clinical comparison of pegged and keeled glenoid components using modern cementing techniques: midterm results of a prospective randomized study

Glenoid component loosening remains a significant issue after anatomic shoulder arthroplasty. Pegged glenoid components have shown better lucency rates than keeled components in the short term; however, midterm to long-term results have not fully been determined. We previously reported early outcomes of the current randomized controlled group of patients, with higher glenoid lucency rates in those with a keeled glenoid. The purpose of this study was to evaluate the radiographic and clinical outcomes of these components at minimum 5-year follow-up. Fifty-nine total shoulder arthroplasties were performed in patients with primary glenohumeral osteoarthritis. Patients were randomized to receive either a pegged or keeled glenoid component. Three raters graded radiographic glenoid lucencies. Clinical outcome scores and active mobility outcomes were collected preoperatively and at yearly postoperative appointments. Of the 46 shoulders meeting the inclusion criteria, 38 (82.6%) were available for minimum 5-year radiographic follow-up. After an average of 7.9 years, radiographic lucency was present in 100% of pegged and 91% of keeled components (P = .617). Grade 4 or 5 lucency was present in 44% of pegged and 36% of keeled components (P = .743). There were no differences in clinical outcome scores or active mobility outcomes between shoulders with pegged and keeled components at last follow-up. Within the initial cohort, 20% of the keeled shoulders (6 of 30) and 7% of the pegged shoulders (2 of 29) underwent revision surgery (P = .263). Kaplan-Meier analysis showed no significant difference in survival rates between groups (P = .560). At an average 7.9-year follow-up, non-ingrowth, all-polyethylene pegged glenoid implants are equivalent to keeled implants with respect to radiolucency, clinical outcomes, and need for revision surgery.

Clinical and radiological results 7years after Copeland shoulder resurfacing arthroplasty in patients with primary glenohumeral osteoarthritis: an independent multicentre retrospective study.

The aim of this multicentre cohort study was to evaluate the midterm outcomes and survival after cementless stemless resurfacing arthroplasty (CSRA) in a series of 33 shoulders in 27 patients with primary osteoarthritis. Clinical outcome assessment included: Constant-Murley score (CMS); Simple Shoulder Test (SST); Disability of Arm, Shoulder, Hand (DASH); EuroQol-5D (EQ-5D) utility scores; Numerous Rating Scale (NRS) for pain. Radiographs were assessed by two independent observers for oversizing, radiolucency, glenohumeral subluxation, glenoid erosion and subsidence. Correlations between the clinical and radiological outcomes were calculated. Complications were registered, and revision and survival rates were calculated. Mean age at time of surgery and mean follow-up time were, respectively, 67.7 (range 50.2-85.1) and 7.2years (range 5.7-9.3years). Means (SD) for CMS, age- and gender-adjusted CMS, SST, DASH and EQ-5D utility scores were: 56.4 (20.2), 76.5 (25.0), 54.0 (29.8), 37.6 (23.3) and 0.8 (0.1), respectively. NRS for pain was 2.0 and 3.8, respectively, in rest and during activities. Radiographic assessment of the CSRAs showed oversizing in 54.5%; radiolucency in 18.2%; superior glenohumeral subluxation in 33.3%; glenoid erosion in 45.5%; and subsidence in 3.0%. Perioperative complications did not occur. Revision surgery was performed in one patient (3.0%). For primary osteoarthritis, the CSRA showed good clinical but poor radiological outcomes at midterm follow-up.

Clinical and Radiographic Outcomes of the Ream-and-Run Procedure for Primary Glenohumeral Arthritis.

The ream-and-run procedure can provide improvement in shoulder function and comfort for selected patients with primary glenohumeral arthritis who wish to avoid a prosthetic glenoid component. The purpose of this study was to evaluate factors associated with medialization of the humeral head after this procedure as well as the relationship of medialization to the clinical outcome. We collected patient, shoulder, and procedure characteristics along with Simple Shoulder Test (SST) scores before surgery and at the time of follow-up. Medialization was determined by comparing the position of the humeral head prosthesis in relation to the scapula on postoperative baseline radiographs made within 6 weeks after surgery with that on comparable follow-up radiographs made ≥18 months after surgery. Two-year clinical outcomes were available for 101 patients (95% were male). Comparable radiographs at postoperative baseline and follow-up evaluations were available for 50 shoulders. For all patients, the mean SST score (and standard deviation) increased from 4.9 ± 2.8 preoperatively to 10.3 ± 2.4 at the latest follow-up (p < 0.001). Significant clinical improvement was observed for glenoid types A2 and B2. Shoulders with a type-A2 glenoid morphology, with larger preoperative scapular body-glenoid angles, and with lower preoperative SST scores, were associated with the greatest clinical improvement. Clinical outcome was not significantly associated with the amount of medialization. The ream-and-run procedure can be an effective treatment for advanced primary glenohumeral osteoarthritis in active patients. Further study will be necessary to determine whether medialization affects the clinical outcome with follow-up of >2 years. Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Reverse shoulder arthroplasty

Reverse polarity total shoulder arthroplasty is an innovation primarily designed to treat the rotator cuff-deficient shoulder by increasing constraint and thereby addressing the challenges of pseudoparalysis. Forward elevation can be regained, pain and quality of life can be improved. Recently, there has been an expansion in both the breadth of indications and the volume of surgeries performed. We aim to review current practice and direction of travel. The impact of rotator cuff tear arthropathy (CTA) is often significant and disabling. This condition is associated with painful arthrosis of the shoulder in conjunction with instability, which allows the humeral head to escape antero-superiorly. The resulting loss of function in the shoulder is aptly described as ‘pseudoparalysis’. Figure 1 shows the normal deltoid function around a shoulder with an intact soft-tissue envelope, and the superior migration that results when the superiorly directed force vector is not neutralised. Conventional anatomical arthroplasty of the shoulder fails to restore function in these patients due to the inadequate stability of the joint around a central point of pivot, combined with an inability of the surrounding muscles to compensate for a weak or torn rotator cuff. Fig. 1 Proximal migration in cuff tear arthropathy with resulting deltoid dysfunction- schematic This combination results in a complex and disabling condition that has vexed shoulder surgeons since the early days of development in shoulder arthroplasty systems. A better understanding of shoulder biomechanics and the mechanisms of failure in total shoulder arthroplasty led to the development of reverse shoulder arthroplasty (RSA) designs. While the original indication was CTA, there has been a rapid expansion of indications to include a spectrum of pathologies: proximal humeral fractures and trauma sequelae; massive cuff tears; tumours; primary glenohumeral osteoarthritis (OA); and the revision of failed shoulder arthroplasties. Themistocles Gluck most likely developed a shoulder arthroplasty in the …

The incidence and effect of fatty atrophy, positive tangent sign, and rotator cuff tears on outcomes after total shoulder arthroplasty

Treatment choices for total shoulder arthroplasty (TSA) in the absence of full-thickness rotator cuff tears (RCTs) are not clearly defined in current literature. This study investigated the prevalence and effect of preoperative partial-thickness RCTs and muscular degenerative changes on postoperative outcomes after TSA. Medical records and magnetic resonance imaging studies were reviewed for patients who underwent TSA for primary glenohumeral osteoarthritis with minimum 2-year follow-up to determine preoperative tear classification, Goutallier grade, and supraspinatus tangent sign. Postoperative pain on the visual analog scale, range of motion, and patient outcomes scores were obtained to correlate preoperative RCT status, Goutallier grading, tangent sign, and postoperative outcomes. Patients with full-thickness RCT on preoperative magnetic resonance imaging were excluded. Forty-five patients met all inclusion criteria (average age, 65 ± 10 years; average follow-up, 43 months). Of the patients undergoing TSA, 40% had a significant (>50% thickness) partial RCT. Grade 3 to 4 Goutallier changes were noted in 22% of all patients, and 13% demonstrated grade 3 to 4 changes in the context of no tear. Positive tangent sign was present in 7% of all patients. The preoperative Goutallier grade of the infraspinatus was significantly negatively correlated with postoperative forward elevation (P = .02) and external rotation (P = .05), but rotator cuff pathology, including tear status, Goutallier grade, and the presence of a tangent sign, did not correlate with postoperative functional outcome scores. Even in the absence of a full-thickness RCT, rotator cuff atrophy, fatty infiltration, and partial thickness tearing are common findings. Although postoperative range of motion is correlated to Goutallier changes of the infraspinatus, rotator cuff pathology is not correlated to outcomes after TSA; therefore, one may proceed with TSA without concern of their effect on postoperative outcomes.

The medium- and long-term outcome of total shoulder arthroplasty for primary glenohumeral osteoarthritis in middle-aged patients.

Promising medium-term results from total shoulder arthroplasty (TSA) have been reported for the treatment of primary osteoarthritis in young and middle-aged patients. The aim of this study was to evaluate the long-term functional and radiological outcome of TSA in the middle-aged patient. The data of all patients from the previous medium-term study were available. At a mean follow-up of 13 years (8 to 17), we reviewed 21 patients (12 men, nine women, 21 shoulders) with a mean age of 55 years (37 to 60). The Constant-Murley score (CS) with its subgroups and subjective satisfaction were measured. Radiological signs of implant loosening were analysed. Two shoulders (two patients) were revised and in two shoulders of two different patients, revision surgery was recommended. The mean CS increased from 23.3 (10 to 45) pre-operatively to 56.5 (26 to 81; p < 0.0001), but with a decrease in CS from 62.8 (38 to 93) to 56.5 (26 to 81) between medium- and long-term follow-up (p = 0.01). Without revision surgery, 18 patients (95%) rated their result as good or very good. The mean radiolucent line score for the glenoid components increased from 1.8 (0 to 6) to 8.2 (2 to 18) between medium- and long-term follow-up (p < 0.001). TSA in young and middle-aged patients leads to improvement in clinical function and a relatively high satisfaction rate. However, clinical or radiological glenoid loosening worsens in the long term. Further studies are needed to optimise the treatment options in this patient population. Cite this article: Bone Joint J 2017;99-B:939-43.

Outcome and revision rate of uncemented glenohumeral resurfacing (C.A.P.) after 5-8years.

Resurfacing of the glenohumeral joint for patients with glenohumeral arthritis has gained popularity since the first introduction. We report the mid-term results of the Global C.A.P. uncemented resurfacing shoulder prosthesis (DePuy Synthes). From January 2007 to December 2009, 48 humeral cementless resurfacing prostheses in 46 patients were performed. All patients were diagnosed with primary glenohumeral osteoarthritis. Patients were contacted for review; the Constant Score, visual analog pain scale, Dutch Simple Shoulder Test, SF-12 scores and physical examination were assessed both preoperatively and yearly postoperatively. Complications and revision surgery were documented. Radiographs were evaluated for component size, offset, inclination, height, loosening and subluxation. Forty-six patients (12 males) with a mean age of 72years old (range 59-89) were included. At a mean 6.4-year follow-up (range 5-8), the Constant Score, visual analog pain scale and the Dutch Simple Shoulder Test scores improved significantly (p < 0.05) from baseline. Three patients were lost to follow-up. One patient died and two patients were not able to attend the follow-up appointments, due to other health-related issues. Eleven patients (23%) had a revision operation. The most important findings of this study of the Global C.A.P. shoulder resurfacing arthroplasty were an increase of range of motion, a reduction of pain complaints, but a concerning high rate of revision after mid-term follow-up. Therapeutic Level IV.

Cement stress predictions after anatomic total shoulder arthroplasty are correlated with preoperative glenoid bone quality

We hypothesized that biomechanical parameters typically associated with glenoid implant failure after anatomic total shoulder arthroplasty (aTSA) would be correlated with preoperative glenoid bone quality. We developed an objective automated method to quantify preoperative glenoid bone quality in different volumes of interest (VOIs): cortical bone, subchondral cortical plate, subchondral bone after reaming, subchondral trabecular bone, and successive layers of trabecular bone. Average computed tomography (CT) numbers (in Hounsfield units [HU]) were measured in each VOI from preoperative CT scans. In parallel, we built patient-specific finite element models of simulated aTSAs to predict cement stress, bone-cement interfacial stress, and bone strain around the glenoid implant. CT measurements and finite element predictions were obtained for 20 patients undergoing aTSA for primary glenohumeral osteoarthritis. We tested all linear correlations between preoperative patient characteristics (age, sex, height, weight, glenoid bone quality) and biomechanical predictions (cement stress, bone-cement interfacial stress, bone strain). Average CT numbers gradually decreased from cortical (717 HU) to subchondral and trabecular (362 HU) bone. Peak cement stress (4-10 MPa) was located within the keel hole, above the keel, or behind the glenoid implant backside. Cement stress, bone-cement interfacial stress, and bone strain were strongly negatively correlated with preoperative glenoid bone quality, particularly in VOIs behind the implant backside (subchondral trabecular bone) but also in deeper trabecular VOIs. Our numerical study suggests that preoperative glenoid bone quality is an important parameter to consider in aTSA, which may be associated with aseptic loosening of the glenoid implant. These initial results should now be confronted with clinical and radiologic outcomes.

Radiographs and computed tomography scans show similar observer agreement when classifying glenoid morphology in glenohumeral arthritis

Glenohumeral subluxation and glenoid morphology are commonly evaluated in primary osteoarthritis by use of the Walch classification. The reliability of this classification system has been analyzed only by computed tomography (CT). The purpose of this study was to determine the reliability of plain axillary radiographs compared with CT scans. Three shoulder surgeons blindly and independently evaluated the radiographs and CT scans of 75 consecutive shoulders with primary glenohumeral osteoarthritis. Each observer classified all shoulders according to Walch in 4 separate sessions, each 6 weeks apart. There were 2 sessions using only radiographs and 2 using only CT scans. The order of shoulders evaluated was randomized. The first reading by the most senior observer based on CT was arbitrarily used as the "gold standard" (A1, 21; A2, 13; B1, 12; B2, 28; C, 1). The average intraobserver agreement for radiographs was 0.66 (substantial; 0.66, 0.59, and 0.74 for each observer). The average intraobserver agreement for CT scans was 0.60 (moderate; 0.53, 0.61, and 0.65). Pairwise comparisons between observers showed higher agreement for radiographs than for CT scans (0.48 vs. 0.39). The average agreement for observations on radiographs and CT scans was 0.42 (moderate; 0.40, 0.37, and 0.50). In this study, intraobserver agreement using the Walch classification based on axillary radiographs was substantial and compared favorably with agreement based on CT scans. The Walch classification provides a useful frame of reference when assessing subluxation and glenoid morphology in primary glenohumeral osteoarthritis, but not unlike other classification systems, it does not allow perfect agreement among observers.

Paper #29 - Anatomic shoulder arthroplasty with plication of the posterior capsule compared to reverse shoulder arthroplasty for osteoarthritis with B2 glenoid: a matched cohort study

Introduction: A subset of patients with primary glenohumeral osteoarthritis presents with posterior subluxation and eccentric posterior glenoid bone loss (B2 glenoid). Posterior capsular plication is sometimes required to balance the shoulder when performing an anatomic shoulder arthroplasty. More recently, reverse arthroplasty has been advocated for glenohumeral osteoarthritis with severe posterior subluxation. To date, no study has compared these two alternatives for shoulders with marked posterior subluxation. The purpose of this study was to compare the clinical and radiographic outcomes of a matched cohort of shoulders with B2 glenoids treated with either anatomic total shoulder arthroplasty (TSA) with plication of the posterior capsule or a reverse shoulder arthroplasty (RSA). Methods: All shoulder arthroplasties performed for glenohumeral osteoarthritis at a single institution between 1975 and 2013 were reviewed to identify two matched cohorts. Group 1 included 15 TSA in shoulders with B2 glenoids that required posterior capsule plication. Group 2 included 16 RSA in shoulders with B2 glenoids. Both groups were similar in terms of age (70 ± 7.5 years vs 72 ± 5.4 years), BMI (31 ± 3.9 vs 32. ± 1.6) and follow-up (42.8 ± 18.4 vs 35.1 ± 14.2). The records of these patients were reviewed to determine pain, range of motion (ROM), strength, Neer rating scale, simple shoulder test, ASES score, satisfaction, complications, reoperations, radiolucency lines and implant loosening. Radiographic information was obtained preoperatively, in the immediate postoperative period and at last radiographic follow-up. Results: With the numbers available, at most recent follow-up, there were no significant differences in pain (P = .2), forward flexion (P = .7), external rotation (P = .5), internal rotation (P = .4), forward flexion strength (P = .3), abduction strength (P = .8), external rotation strength (P = .5), internal rotation strength (P = .8), ASES scores (P = .08), or satisfaction (P = .3). The simple shoulder test score was significantly better in TSA compared to RSA (10.6 vs 8.5, P = .01). There were no reoperations in either group. Radiographically, in the TSA group there were 2 shoulders with glenoid loosening, 2 shoulders with progressive cuff insufficiency, and 1 shoulder with recurrent posterior subluxation and 1 additional shoulder with recurrent posterior subluxation and glenoid loosening. In the RSA, there were no cases of loosening or notching. Conclusions: The overall clinical outcome of anatomic TSA in patients with a B2 glenoid and subluxation requiring posterior capsular plication seems to be similar to the outcome of RSA in patients with a B2 glenoid. However, the rate of radiographic glenoid loosening, cuff insufficiency, and recurrent posterior subluxation after TSA remains of concern.

Interest in the glenoid hull method for analyzing humeral subluxation in primary glenohumeral osteoarthritis

Posterior humeral subluxation is the main cause of failure of total shoulder arthroplasty. We aimed to compare humeral head subluxation in various reference planes and to search for a correlation with retroversion, inclination, and glenoid wear. We included 109 computed tomography scans of primary glenohumeral osteoarthritis and 97 of shoulder problems unrelated to shoulder osteoarthritis (controls); all computed tomography scans were reconstructed in the anatomic scapular plane and the glenoid hull plane that we defined. In both planes, we measured retroversion, inclination, glenohumeral offset (Walch index), and scapulohumeral offset. Retroversion in the scapular plane (Friedman method) was lower than that in the glenoid hull plane for controls and for arthritic shoulders. The threshold of scapulohumeral subluxation was 60% and 65% in the scapular plane and glenoid hull plane, respectively. The mean upward inclination was lower in the scapular plane (Churchill method) than in the glenoid hull plane (Maurer method). In the glenoid hull plane, 35% of type A2 glenoids showed glenohumeral offset greater than 75%, with mean retroversion of 25.6° ± 6° as compared with 7.5° ± 7.2° for the "centered" type A2 glenoids (P < .0001) and an upward inclination of -1.4° ± 8° and 6.3° ± 7° (P = .03), respectively. The correlation between retroversion and scapulohumeral offset was r = 0.64 in the glenoid hull plane and r = 0.59 in the scapular plane (P < .05). Measurement in the glenoid hull plane may be more accurate than in the scapular plane. Thus, the glenoid hull method allows for better understanding type B3 of the modified Walch classification.

Responsiveness and Internal Validity of Common Patient-Reported Outcome Measures Following Total Shoulder Arthroplasty.

The Constant-Murley (Constant) score, Western Ontario Osteoarthritis of the Shoulder (WOOS) index, American Shoulder and Elbow Surgeons (ASES) score, and Single Assessment Numeric Evaluation (SANE) score are commonly used to assess patient-reported function following shoulder surgery. However, psychometric properties for these tools are mostly unknown for patients with primary glenohumeral arthritis who have undergone anatomic total shoulder arthroplasty (TSA). The purposes of this study were to (1) compare the responsiveness and internal validity between the 4 patient-reported outcomes (PROs) and (2) identify PRO score values associated with patient satisfaction after TSA. A total of 234 primary TSAs were performed for primary glenohumeral osteoarthritis with a 2-year or greater follow-up. The Constant score, WOOS index, ASES score, SANE score, and patient satisfaction were assessed preoperatively and 2 to 5 years postoperatively. Effect sizes, standardized response means, and relative efficiency were calculated to determine responsiveness, and internal validity was determined via the presence of floor and/or ceiling effects. Receiver operator characteristic (ROC) curves were constructed to identify the minimum outcome score that could correctly identify a satisfied patient. At final follow-up, 88% of patients were satisfied. The PROs had large effect sizes and standardized response means (≥0.83). The minimum score that most correctly identified a patient as satisfied was 78 for ASES score, 18 for WOOS index, 73 for Constant score, and 58 for SANE score. However, the ASES score, WOOS index, and SANE score had marked postoperative ceiling effects, whereas the Constant score was the most responsive and internally valid tool. These results suggest that the Constant score should serve as the primary PRO for patients with primary glenohumeral arthritis, whereas the WOOS index, ASES score, and SANE score could be supplementary assessments. [Orthopedics. 2017; 40(3):e513-e519.].

Classifications in Brief: Walch Classification of Primary Glenohumeral Osteoarthritis.

Classifications in Brief: Walch Classification of Primary Glenohumeral Osteoarthritis.

Reverse Total Shoulder Arthroplasty without Bone-Grafting for Severe Glenoid Bone Loss in Patients with Osteoarthritis and Intact Rotator Cuff.

Treating shoulders with osteoarthritis, an intact rotator cuff, and substantial glenoid bone loss is challenging. One option is reaming the glenoid flat and inserting a reverse prosthesis. This study reports the subjective, objective, and radiographic results of reverse total shoulder arthroplasty (RTSA) in this population. We retrospectively reviewed 42 consecutive patients (23 women; mean age, 71 years [range, 53 to 89 years]) with primary glenohumeral osteoarthritis, intact rotator cuffs, and Walch type-A2 (n = 19), B2 (n = 5), or C glenoids (n = 18) who had undergone a total of 42 RTSAs with glenoid reaming without bone-grafting between 2008 and 2013 (mean follow-up, 36 months [range, 24 to 66 months]). All patients were evaluated before and after surgery subjectively (using a visual analog scale for pain and 5 shoulder-specific outcome instruments), objectively (with goniometric examination of shoulder range of motion), and radiographically (to assess baseplate loosening and degree of scapular notching). One baseplate (2%) failed, requiring revision surgery. There were no other signs of baseplate loosening in any patient at the last follow-up. Preoperatively to postoperatively, pain improved significantly (p < 0.001), as did all patient-reported outcome measures and the following range-of-motion parameters (p ≤ 0.001): active abduction, active flexion, and active external rotation with the arm elevated 90°. Eight (19%) of the patients had notching. RTSA without bone-grafting and with medialization of the baseplate in patients with osteoarthritis and severe glenoid bone loss resulted in significant improvement in pain and function with reliable short-term implant survivorship and may be a good alternative to anatomical TSA. Longer follow-up is needed to determine the relative advantages and disadvantages. This was an "off-label" indication for this device. Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

A modification to the Walch classification of the glenoid in primary glenohumeral osteoarthritis using three-dimensional imaging

Since Walch and colleagues originally classified glenoid morphology in the setting of glenohumeral osteoarthritis, several authors have reported varying levels of interobserver and intraobserver reliability. We propose several modifications to the Walch classification that we hypothesize will increase interobserver and intraobserver reliability. We propose the addition of the B3 and D glenoids and a more precise definition of the A2 glenoid. The B3 glenoid is monoconcave and worn preferentially in its posterior aspect, leading to pathologic retroversion of at least 15° or subluxation of 70%, or both. The D glenoid is defined by glenoid anteversion or anterior humeral head subluxation. The A2 glenoid has a line connecting the anterior and posterior native glenoid rims that transects the humeral head. Using 3-dimensional computed tomography glenoid reconstructions, 3 evaluators used the original Walch classification and the modified Walch classification to classify 129 nonconsecutive glenoids on 4 separate occasions. Reliabilities were assessed by calculating κ coefficients. Interobserver reliabilities improved from an average of 0.391 (indicating fair agreement) using the original classification to an average of 0.703 (substantial agreement) using the modified classification. Intraobserver reliabilities improved from an average of 0.605 (moderate agreement) to an average of 0.882 (nearly perfect agreement). When 3-dimensional glenoid reconstructions and the modified Walch classification described herein are used, improved interobserver and intraobserver reliabilities are obtained.

A three-dimensional comparative study on the scapulohumeral relationship in normal and osteoarthritic shoulders

Eccentric loading due to humeral translation is associated with worse clinical outcomes in hemiarthroplasty and total shoulder arthroplasty. The purpose of this study was to evaluate the 3-dimensional relationship of the humeral head to the scapula (scapulohumeral relationship) in nonpathologic shoulders and in shoulders with primary osteoarthritis. Three-dimensional reconstructions of computed tomography scans of 151 nonpathologic shoulders (control group) and 110 shoulders with primary glenohumeral arthritis (OA group) were analyzed by measuring the anterior-posterior, inferior-superior, and medial-lateral position of the humeral head in relation to the scapula. Shoulders were classified as centered (type A) or posteriorly subluxed (type B) according to the Walch classification of glenoid morphology. Reproducibility and differences in scapulohumeral relationship were statistically analyzed. The scapulohumeral relationship could be determined reliably: the intraclass correlation coefficient ranged between 0.780 and 0.978; the typical error of measurement ranged between 2.4% and 5.0%. Both type A and type B shoulders showed significant posterior translation of the humeral head (P <.001). Type B shoulders had significantly more posterior translation than type A shoulders (P <.001). A tendency of inferior translation was noted, although with only marginal statistical significance (P = .051). In each morphology class, a medial deviation of the humeral head, representing a reduced glenohumeral distance, was measured (P <.001). The main characteristics of primary glenohumeral osteoarthritis are posterior humeral head translation relative to the scapula, reduced glenohumeral distance, and a tendency toward inferior humeral head translation in both type A and type B shoulders.