Knowledge of the premorbid glenoid shape and the morphological changes the bone undergoes in patients with glenohumeral arthritis can improve surgical outcomes in total and reverse shoulder arthroplasty. Several studies have previously used scapular statistical shape models (SSMs) to predict premorbid glenoid shape and evaluate glenoid erosion properties. However, current literature suggests no studies have used scapular SSMs to examine the changes in glenoid surface area in patients with glenohumeral arthritis. Therefore, the purpose of this study was to compare the glenoid articular surface area between pathologic glenoid cavities from patients with glenohumeral arthritis and their predicted premorbid shape using a scapular SSM. Furthermore, this study compared pathologic glenoid surface area with that from virtually eroded glenoid models created without influence from internal bone remodelling activity and osteophyte formation. It was hypothesized that the pathologic glenoid cavities would exhibit the greatest glenoid surface area despite the eroded nature of the glenoid and the medialization, which in a vault shape, should logically result in less surface area. Computer tomography (CT) scans from 20 patients exhibiting type A2 glenoid erosion according to the Walch classification [Walch et al., 1999] were obtained. A scapular SSM was used to predict the premorbid glenoid shape for each scapula. The scapula and humerus from each patient were automatically segmented and exported as 3D object files along with the scapular SSM from a pre-operative planning software. Each scapula and a copy of its corresponding SSM were aligned using the coracoid, lateral edge of the acromion, inferior glenoid tubercule, scapular notch, and the trigonum spinae. Points were then digitized on both the pathologic humeral and glenoid surfaces and were used in an iterative closest point (ICP) algorithm in MATLAB (MathWorks, Natick, MA, USA) to align the humerus with the glenoid surface. A Boolean subtraction was then performed between the scapular SSM and the humerus to create a virtual erosion in the scapular SSM that matched the erosion orientation of the pathologic glenoid. This led to the development of three distinct glenoid models for each patient: premorbid, pathologic, and virtually eroded (Fig. 1). The glenoid surface area from each model was then determined using 3-Matic (Materialise, Leuven, Belgium). Figure 1. (A) Premorbid glenoid model, (B) pathologic glenoid model, and (C) virtually eroded glenoid model. The average glenoid surface area for the pathologic scapular models was 70% greater compared to the premorbid glenoid models (P < 0 .001). Furthermore, the surface area of the virtual glenoid erosions was 6.4% lower on average compared to the premorbid glenoid surface area (P=0.361). The larger surface area values observed in the pathologic glenoid cavities suggests that sufficient bone remodelling exists at the periphery of the glenoid bone in patients exhibiting A2 type glenohumeral arthritis. This is further supported by the large difference in glenoid surface area between the pathologic and virtually eroded glenoid cavities as the virtually eroded models only considered humeral anatomy when creating the erosion. For any figures or tables, please contact the authors directly

We report the use of the reverse shoulder prosthesis in the revision of a failed shoulder hemiarthroplasty in 19 shoulders in 18 patients (7 men, 11 women) with severe pain and loss of function. The primary procedure had been undertaken for glenohumeral arthritis associated with severe rotator cuff deficiency. Statistically significant improvements were seen in pain and functional outcome. After a mean follow-up of 44 months (24 to 89), mean forward flexion improved by 26.4° and mean abduction improved by 35°. There were six prosthesis-related complications in six shoulders (32%), five of which had severe bone loss of the glenoid, proximal humerus or both. Three shoulders (16%) had non-prosthesis related complications. The use of the reverse shoulder prosthesis provides improvement in pain and function for patients with failure of a hemiarthroplasty for glenohumeral arthritis and rotator cuff deficiency. However, high rates of complications were associated with glenoid and proximal humeral bone loss

Introduction. The treatment of glenohumeral arthritis in a young patient poses a significant challenge. Factors that affect decision making include higher activity levels, greater expectations, and concerns of implant longevity. Conflicting results have been reported in the literature. The purpose of this study is to report on our results for resurfacing of the humeral head combined with a biologic glenoid resurfacing using a soft tissue allograft for the treatment of glenohumeral osteoarthritis. Methods. From 2003 to 2009 a retrospective multi-center review of 15 humeral and biologic glenoid resurfacing procedures with a mean age of 36.5 yrs. was performed. Indications for surgery included a diagnosis of glenohumeral arthritis non-responsive to conservative treatment. Exclusion criteria included major glenoid osseous deficiency, advanced rheumatoid arthritis, and chronic infection. Results. Mean follow-up of 57.1 months showed that on average active forward elevation improved from 126.8° to 136° and external rotation improved from 27.1° to 35.3°. The mean pre-operative and post-operative VAS score only improved from 7.9 to 5.1. Five (29%) patients were converted a total shoulder arthroplasty (TSA) at an average of 24 months with no complications in the remaining patients. Discussion. The clinical outcome of humeral head resurfacing with soft tissue resurfacing of the glenoid has not yielded encouraging results, as both pain and function are not significantly improved. Due to the disappointing results of this procedure and high revision rate, it is no longer these authors primary treatment option for OA in the young. Determining the optimal treatment for osteoarthritis in the young patient is still being investigated

Inherent disadvantages of reverse shoulder arthroplasty designs based on the Grammont concept have raised a renewed interest in less-medialised designs and techniques. The aim of this study was to evaluate the outcome of reverse shoulder arthroplasty (RSA) with the fully-constrained, less-medialised, Bayley–Walker prosthesis performed for the treatment of rotator-cuff-deficient shoulders with glenohumeral arthritis. A total of 97 arthroplasties in 92 patients (53 women and 44 men, mean age 67 years (standard deviation (sd) 10, (49 to 85)) were retrospectively reviewed at a mean follow-up of 50 months ((sd 25) (24 to 96)). The mean Oxford shoulder score and subjective shoulder value improved from 47 (sd 9) and 24 points (sd 18) respectively before surgery to 28 (sd 11) and 61 (sd 24) points after surgery (p <  0.001). The mean pain at rest decreased from 5.3 (sd 2.8) to 1.5 (sd 2.3) (p < 0.001). The mean active forward elevation and external rotation increased from 42^°(sd 30) and 9^° (sd 15) respectively pre-operatively to 78^° (sd 39) and 24^° (sd 17) post-operatively (p < 0.001). A total of 20 patients required further surgery for complications; 13 required revision of components. No patient developed scapular notching.

The Bayley–Walker prosthesis provides reliable pain relief and reasonable functional improvement for patients with symptomatic cuff-deficient shoulders. Compared with other designs of RSA, it offers a modest improvement in forward elevation, but restores external rotation to some extent and prevents scapular notching. A longer follow-up is required to assess the survival of the prosthesis and the clinical performance over time.

Cite this article: Bone Joint J 2014;96-B:936–42.

Introduction

Resurfacing of the glenohumeral joint has gained popularity since its first introduction in 1958. Advantages of resurfacing over conventional shoulder arthroplasty include preservation of humeral bone stock, closer replication of individual anatomy, reduction of periprosthetic fracture risk, non-violation of medullary canal, and ease of revision to a stemmed component if needed.

Purpose: The purpose of this retrospective studies is to evaluate the real effectiveness, with clinical and radiologic evalutation, of the eccentric glenosphere and also how a correct position can prevent the scapular notching.

Material and Methods: We inplanted in 18 patients, with eccentric arthopaty, a 36 mm eccentric glenoshere.24 months’ clinical and radiographic follow up. All patient were assessed preoperatively and postoperatively with the Constant Score. In the post-operative radiographic control we have taken in consideration: the presence of notching, psna (prosthesis-scapular neck angle), pgrd (peg glenoid distance), glenoid inclination, craniocaudal position of the glenosphere in relation to the glenoid.

Results: The ROM increased in all level. All of the 18 shoulder had no notching. The craniocaudal position of the glenosphere in relation to the glenoid is 4,3 mm. The PSNA was 92° and the PGRD was 21.2.

Conclusion: The inferior scapular notching is the most important complicance of reverse prosthesis. The results of our study indicate that : the correct positioning of the metal back, at the center of the glenoid (better biomechanics stability), without overhang and with eccentric glenosphere, permits to lower the center of rotation of 4 mm avoiding the notch and so increasing the adduction and abduction range of motion.

Aims

Both anatomical and reverse total shoulder arthroplasty (aTSA and rTSA) provide functional improvements. A reported benefit of aTSA is better range of motion (ROM). However, it is not clear which procedure provides better outcomes in patients with limited foward elevation (FE). The aim of this study was to compare the outcome of aTSA and rTSA in patients with glenohumeral osteoarthritis (OA), an intact rotator cuff, and limited FE.

Aims

To determine the incidence and timing of post-operative fevers following shoulder arthroplasty and the resulting investigations performed.

Aims. Corticosteroid injections are often used to manage glenohumeral arthritis in patients who may be candidates for future total shoulder arthroplasty (TSA) or reverse shoulder arthroplasty (rTSA). In the conservative management of these patients, corticosteroid injections are often provided for symptomatic relief. The purpose of this study was to determine if the timing of corticosteroid injections prior to TSA or rTSA is associated with changes in rates of revision and periprosthetic joint infection (PJI) following these procedures. Methods. Data were collected from a national insurance database from January 2006 to December 2017. Patients who underwent shoulder corticosteroid injection within one year prior to ipsilateral TSA or rTSA were identified and stratified into the following cohorts: < three months, three to six months, six to nine months, and nine to 12 months from time of corticosteroid injection to TSA or rTSA. A control cohort with no corticosteroid injection within one year prior to TSA or rTSA was used for comparison. Univariate and multivariate analyses were conducted to determine the association between specific time intervals and outcomes. Results. In total, 4,252 patients were included in this study. Among those, 1,632 patients (38.4%) received corticosteroid injection(s) within one year prior to TSA or rTSA and 2,620 patients (61.6%) did not. On multivariate analysis, patients who received corticosteroid injection < three months prior to TSA or rTSA were at significantly increased risk for revision (odds ratio (OR) 2.61 (95% confidence interval (CI) 1.77 to 3.28); p < 0.001) when compared with the control cohort. However, there was no significant increase in revision risk for all other timing interval cohorts. Notably, Charlson Comorbidity Index ≥ 3 was a significant independent risk factor for all-cause revision (OR 4.00 (95% CI 1.40 to 8.92); p = 0.036). Conclusion. There is a time-dependent relationship between the preoperative timing of corticosteroid injection and the incidence of all-cause revision surgery following TSA or rTSA. This analysis suggests that an interval of at least three months should be maintained between corticosteroid injection and TSA or rTSA to minimize risks of subsequent revision surgery. Cite this article: Bone Joint J 2022;104-B(5):620–626

Background. Rotator cuff atrophy evaluated with computed tomography scans has been associated with asymmetric glenoid wear and humeral head subluxation in glenohumeral arthritis. Magnetic resonance imaging has increased sensitivity for identifying rotator cuff pathology and has not been used to investigate this relationship. The purpose of this study was to use MRI to assess the association of rotator cuff muscle atrophy and glenoid morphology in primary glenohumeral arthritis. Methods. 132 shoulders from 129 patients with primary GHOA were retrospectively reviewed and basic demographic information was collected. All patients had MRIs that included appropriate orthogonal imaging to assess glenoid morphology and rotator cuff pathology and were reviewed by two senior surgeons. All patients had intact rotator cuff tendons. Glenoid morphology was assigned using the modified-Walch classification system (types A1, A2, B1, B2, B3, C, and D) and rotator cuff fatty infiltration was assigned using Goutallier scores. Results. 46 (35%) of the shoulders had posterior wear patterns (23 type B2s, 23 type B3s). Both the infraspinatus and teres minor independently had significantly more fatty infiltration in B2 and B3 type glenoids compared to type A glenoids (p<0.001). There was a greater imbalance in posterior rotator cuff muscle fatty atrophy in B2 and B3 type glenoids compared to type A glenoids (p<0.001). However, there was no difference in axial plane imbalance between B2 and B3 glenoids (p=1.00). There was increased amount fatty infiltration of the infraspinatus among B2 and B3-type glenoids compared to type A glenoids on multivariate analysis controlling for age and gender (p<0.001). Conclusions. These results identify significant axial plane rotator cuff muscle imbalances in B2 and B3-type glenoids compared to concentrically worn glenoids, favoring a relative increase in fatty infiltration of the infraspinatus and teres minor compared to the subscapularis in glenoids with patterns of posterior wear. For any figures or tables, please contact authors directly

Patients receiving reverse total shoulder arthroplasty (RTSA) often have osseous erosions because of glenohumeral arthritis, leading to increased surgical complexity. Glenoid implant fixation is a primary predictor of the success of RTSA and affects micromotion at the bone-implant interface. Augmented implants which incorporate specific geometry to address superior erosion are currently available, but the clinical outcomes of these implants are still considered short-term. The objective of this study was to investigate micromotion at the glenoid-baseplate interface for a standard, 3 mm and 6 mm lateralized baseplates, half-wedge, and full-wedge baseplates. It was hypothesized that the mechanism of load distribution from the baseplate to the glenoid will differ between implants, and these varying mechanisms will affect overall baseplate micromotion. Clinical CT scans of seven shoulders (mean age 69 years, 10°-19° glenoid inclinations) that were classified as having E2-type glenoid erosions were used to generate 3D scapula models using MIMICS image processing software (Materialise, Belgium) with a 0.75 mm mesh size. Each scapula was then repeatedly virtually reconstructed with the five implant types (standard,3mm,6mm lateralized, and half/full wedge; Fig.1) positioned in neutral version and inclination with full backside contact. The reconstructed scapulae were then imported into ABAQUS (SIMULIA, U.S.) finite element software and loads were applied simulating 15°,30°,45°,60°,75°, and 90° of abduction based on published instrumented in-vivo implant data. The micromotion normal and tangential to the bone surface, and effective load transfer area were recorded for each implant and abduction angle. A repeated measures ANOVA was used to perform statistical analysis. Maximum normal micromotion was found to be significantly less when using the standard baseplate (5±4 μm), as opposed to the full-wedge (16±7 μm, p=0.004), 3 mm lateralized (10±6 μm, p=0.017), and 6 mm lateralized (16±8 μm, p=0.007) baseplates (Fig.2). The half-wedge baseplate (11±7 μm) also produced significantly less micromotion than the full-wedge (p=0.003), and the 3 mm lateralized produced less micromotion than the full wedge (p=0.026) and 6 mm lateralized (p=0.003). Similarly, maximum tangential micromotion was found to be significantly less when using the standard baseplate (7±4 μm), as opposed to the half-wedge (12±5 μm, p=0.014), 3 mm lateralized (10±5 μm, p=0.003), and 6 mm lateralized (13±6 μm, p=0.003) baseplates (Fig.2). The full wedge (11±3 μm), half-wedge, and 3 mm lateralized baseplate also produced significantly less micromotion than the 6 mm lateralized (p=0.027, p=012, p=0.02, respectively). Both normal and tangential micromotion were highest at the 30° and 45° abduction angles (Fig.2). The effective load transfer area (ELTA) was lowest for the full wedge, followed by the half wedge, 6mm, 3mm, and standard baseplates (Fig.3) and increased with abduction angle. Glenoid baseplates with reduced lateralization and flat backside geometries resulted in the best outcomes with regards to normal and tangential micromotion. However, these types of implants are not always feasible due to the required amount of bone removal, and medialization of the bone-implant interface. Future work should study the acceptable levels of bone removal for patients with E-type glenoid erosion and the corresponding best implant selections for such cases. For any figures or tables, please contact the authors directly

Shoulder arthroplasty is effective at restoring function and relieving pain in patients suffering from glenohumeral arthritis; however, cortex thinning has been significantly associated with larger press-fit stems (fill ratio = 0.57 vs 0.48; P = 0.013)1. Additionally, excessively stiff implant-bone constructs are considered undesirable, as high initial stiffness of rigid fracture fixation implants has been related to premature loosening and an ultimate failure of the implant-bone interface2. Consequently, one objective which has driven the evolution of humeral stem design has been the reduction of stress-shielding induced bone resorption; this in-part has led to the introduction of short stems, which rely on metaphyseal fixation. However, the selection of short stem diametral (i.e., thickness) sizing remains subjective, and its impact on the resulting stem-bone construct stiffness has yet to be quantified. Eight paired cadaveric humeri (age = 75±15 years) were reconstructed with surgeon selected ‘standard’ sized and 2mm ‘oversized’ short-stemmed implants. Standard stem sizing was based on a haptic assessment of stem and broach stability per typical surgical practice. Anteroposterior radiographs were taken, and the metaphyseal and diaphyseal fill ratios were quantified. Each humerus was then potted in polymethyl methacrylate bone cement and subjected to 2000 cycles of compressive loading representing 90º forward flexion to simulate postoperative seating. Following this, a custom 3D printed metal implant adapter was affixed to the stem, which allowed for compressive loading in-line with the stem axis (Fig.1). Each stem was then forced to subside by 5mm at a rate of 1mm/min, from which the compressive stiffness of the stem-bone construct was assessed. The bone-implant construct stiffness was quantified as the slope of the linear portion of the resulting force-displacement curves. The metaphyseal and diaphyseal fill ratios were 0.50±0.10 and 0.45±0.07 for the standard sized stems and 0.50±0.06 and 0.52±0.06 for the oversized stems, respectively. Neither was found to correlate significantly with the stem-bone construct stiffness measure (metaphysis: P = 0.259, diaphysis: P = 0.529); however, the diaphyseal fill ratio was significantly different between standard and oversized stems (P < 0.001, Power = 1.0). Increasing the stem size by 2mm had a significant impact on the stiffness of the stem-bone construct (P = 0.003, Power = 0.971; Fig.2). Stem oversizing yielded a construct stiffness of −741±243N/mm; more than double that of the standard stems, which was −334±120N/mm. The fill ratios reported in the present investigation match well with those of a finite element assessment of oversizing short humeral stems3. This work complements that investigation's conclusion, that small reductions in diaphyseal fill ratio may reduce the likelihood of stress shielding, by also demonstrating that oversizing stems by 2mm dramatically increases the stiffness of the resulting implant-bone construct, as stiffer implants have been associated with decreased bone stimulus4 and premature loosening2. The present findings suggest that even a small, 2mm, variation in the thickness of short stem humeral components can have a marked influence on the resulting stiffness of the implant-bone construct. This highlights the need for more objective intraoperative methods for selecting stem size to provide guidelines for appropriate diametral sizing. For any figures or tables, please contact the authors directly

Background: Rotator cuff tears involving the subscapularis are less common than those involving the posterior superior rotator cuff. The purpose of this study is to report the results of repair of isolated tears of the subscapularis. Methods: Eighty-four shoulders that had undergone open repair of the subscapularis tendon were reviewed. The mean age at surgery was 53.2 years. The mean interval from onset of symptoms to surgery was 12.5 months. Fifty-seven tears were traumatic, and twenty-seven were degenerative in etiology. Twenty-three of the tears involved the superior third of the subscapularis tendon, forty-one involved the superior two thirds, and twenty were complete tears. Fifty-four shoulders had a dislocation or subluxation of the long head of the biceps tendon, while ten shoulders had a rupture of the long head of the biceps tendon. Forty-eight shoulders underwent concomitant biceps tenodesis; thirteen shoulders underwent concomitant biceps tenotomy; and four shoulders underwent concomitant recentering of the biceps. Patients were evaluated clinically and radiographically at a mean fortyfive month follow-up (range 24 to 132 months). Results: The mean Constant score increased from 55.0 points preoperatively to 79.5 points postoperatively (p< 0.001). Seventy-five patients were satisfied or very satisfied with the result. Preoperatively, four patients had mild glenohumeral arthritis. Postoperatively, twenty-five patients had mild glenohumeral arthritis and two patients had moderate glenohumeral arthritis. Tenodesis or tenotomy of the biceps tendon at the time of subscapularis repair was associated with improved subjective and objective results independent of the preoperative condition of the biceps tendon

Shoulder resurfacing arthroplasty is a bone conserving option for patients with glenohumeral arthritis. We report the early results of this procedure at our unit with a minimum follow up of 2 years (mean follow up of 36 months). A historical analysis of prospectively collected clinical data was reviewed on a consecutive series of 22 patients (mean age of 73 years) with end stage gleno-humeral arthrosis who had undergone humeral resurfacing hemiarthroplasty performed by a single surgeon. Pain and function were assessed using the Oxford shoulder score and patient satisfaction was recorded. Radiographs were evaluated for implant loosening. 82% of patients had significant improvement in their oxford shoulder score from pre-operatively to two years post-operatively. Complications included one case of intra-operative conversion to a stemmed hemiarthroplasty due to fracture of the humeral head, one case of adhesive capsulitis that required MUA and arthroscopic capsular release and two cases of revision to a total shoulder replacement for pain. Humeral resurfacing arthroplasty is a viable treatment option for glenohumeral arthritis with good short term results

Total shoulder arthroplasty (TSA) is an effective treatment for end-stage glenohumeral arthritis. The use of high modulus uncemented stems causes stress shielding and induces bone resorption of up to 63% of patients following TSA. Shorter length stems with smaller overall dimensions have been studied to reduce stress shielding, however the effect of humeral short stem varus-valgus positioning on bone stress is not known. The purpose of this study was to quantify the effect of humeral short stem varus-valgus angulation on bone stresses after TSA. Three dimensional models of eight male cadaveric humeri (mean±SD age:68±6 years) were created from computed tomography data using MIMICS (Materialise, Belgium). Separate cortical and trabecular bone sections were created, and the resulting bone models were virtually reconstructed three times by an orthopaedic surgeon using an optimally sized short stem humeral implant (Exactech Preserve) that was placed directly in the center of the humeral canal (STD), as well as rotated varus (VAR) or valgus (VAL) until it was contacting the cortex. Bone was meshed using a custom technique which produced identical bone meshes permitting the direct element-to-element comparison of bone stress. Cortical bone was assigned an elastic modulus of 20 GPa and a Poisson's ratio of 0.3. Trabecular bone was assigned varying stiffness based on CT attenuation. A joint reaction force was then applied to the intact and reconstructed humeri representing 45˚ and 75˚ of abduction. Changes in bone stress, as well as the expected bone response based on change in strain energy density was then compared between the intact and reconstructed states for all implant positions. Both varus and valgus positioning of the humeral stem altered both the cortical and trabecular bone stresses from the intact states. Valgus positioning had the greatest negative effect in the lateral quadrant for both cortical and trabecular bone, producing greater stress shielding than both the standard and varus positioned implant. Overall, the varus and standard positions produced values that most closely mimicked the intact state. Surprisingly, valgus positioning produced large amounts of stress shielding in the lateral cortex at both 45˚ and 75˚ of abduction but resulted in a slight decrease in stress shielding in the medial quadrant directly beneath the humeral resection plane. This might have been a result of direct contact between the distal end of the implant and the medial cortex under loading which permitted load transfer, and therefore load-reduction of the lateral cortex during abduction. Conversely, when the implant was placed in the varus angulation, noticeable departures in stress shielding and changes in bones stress were not observed when compared to the optimal STD position. Interestingly, for the varus positioned implant, the deflection of the humerus under load eliminated the distal stem-cortex contact, hence preventing distal load transfer thus precluding the transfer of load

Aims. Shoulder arthroplasty is effective in the management of end-stage glenohumeral joint arthritis. However, it is major surgery and patients must balance multiple factors when considering the procedure. An understanding of patients’ decision-making processes may facilitate greater support of those considering shoulder arthroplasty and inform the outcomes of future research. Methods. Participants were recruited from waiting lists of three consultant upper limb surgeons across two NHS hospitals. Semi-structured interviews were conducted with 12 participants who were awaiting elective shoulder arthroplasty. Transcribed interviews were analyzed using a grounded theory approach. Systematic coding was performed; initial codes were categorized and further developed into summary narratives through a process of discussion and refinement. Data collection and analyses continued until thematic saturation was reached. Results. Two overall categories emerged: the motivations to consider surgery, and the information participants used to inform their decision-making. Motivations were, broadly, the relief of pain and the opportunity to get on with life and regain independence. When participants’ symptoms and restrictions prevented them enjoying life to a sufficient extent, this provided the motivation to proceed with surgery. Younger participants tended to focus on maintaining employment and recreational activities, and older patients were eager to make the most of their remaining lifetime. Participants gathered information from a range of sources and were keen to optimize their recovery where possible. An important factor for participants was whether they trusted their surgeon and were prepared to delegate responsibility for elements of their care. Conclusion. Relief of pain and the opportunity to get on with life were the primary reasons to undergo shoulder arthroplasty. Participants highlighted the importance of the patient-surgeon relationship and the need for accurate information in an accessible format which is relevant to people of different ages and functional demands. Cite this article: Bone Jt Open 2024;5(7):543–549

Introduction. Total shoulder arthroplasty (TSA) is an effective treatment to restore shoulder function and alleviate pain in the case of glenohumeral arthritis [1]. Stress shielding, which occurs when bone stress is reduced due to the replacement of bone with a stiffer metallic implant, causes bone resorption of up to 9% of the humeral cortical thickness following TSA [2]. Shorter length stems and smaller overall geometries may reduce stress shielding [3], however the effect of humeral head backside contact with the resection plane has not yet been fully investigated on bone stress. Therefore, the purpose of this study was to quantify the effect of humeral head contact conditions on bone stresses following TSA. Methods. 3D models of eight male left cadaveric humeri (68±6 years) were generated from CT data using MIMICS. These were then virtually prepared for reconstruction by an orthopaedic surgeon to accept a short-stem humeral implant (Exactech Equinoxe® Preserve) that was optimally sized and placed centrally in the humeral canal. The humeral head was positioned in the inferior-medial position such that contact was achieved on the medial cortex, and no contact existed on the lateral cortex. Three different humeral head backside contact conditions were investigated (Figure 1); full backside contact (FULL), contact with only the inferior-medial half of the resection (INF), and contact with only the superior-lateral half of the resection (SUP). Cortical bone was assigned an elastic modulus of 20 GPa and a Poisson's ratio of 0.3. Trabecular bone was assigned varying stiffness based on CT attenuation [4]. A joint reaction force was then applied representing 45˚ and 75˚ of abduction [5]. Changes in bone stress, as well as the expected bone response based on change in strain energy density [6] was then compared between the intact and reconstructed states. Results. For cortical bone, the full backside contact altered bone stress by 28.9±5.5% compared to intact, which was significantly less than the superior (37.0±3.9%, P=0.022) and inferior (53.4±3.9%, P<0.001) backside contact conditions. Similar trends were observed for changes in trabecular bone stress relative to the intact state, where the full backside contact altered bone stress by 86.3±27.9% compared to intact, compared to the superior and inferior contact conditions, which altered bone stress by 115.2±45.0% (P=0.309) and 197.4±80.2% (P=0.024), respectively. In terms of expected bone response, both the superior and inferior contact resulted in an increase in bone volume with resorbing potential compared to the full contact (Figure 2). Discussion and Conclusions. The results of this study show that full humeral head backside contact with the humeral resection plane is preferable for short stem humeral TSA implants with the head in the inferior-medial position. As expected, the superior contact typically increased resorption potential in the medial quadrant due to the lack of load transfer, however interestingly the inferior contact increased resorption potential in both the lateral and medial quadrants. Analysis of implant micromotion showed that medial liftoff of the implant occurred, which resulted in a lack of load transfer in the most medial aspect of the resection plane. For any figures or tables, please contact the authors directly

The long head of the biceps tendon has been proposed as a source of pain in patients with rotator cuff tears. The purpose of this study is to evaluate the objective, subjective, and radiographic results of arthroscopic biceps tenotomy in selected patients with rotator cuff tears. Three hundred seven arthroscopic biceps tenotomies were performed in patients with full thickness rotator cuff tears. All patients had previously failed appropriate nonoperative management. Patients were selected for arthroscopic tenotomy if the tear was thought to be irreparable or the patient was older and not willing to participate in the rehabilitation required following rotator cuff repair. One hundred eleven shoulders underwent a concomitant acromioplasty. The mean age at surgery was 64.3 years. The mean preoperative radiographic acromiohumeral interval measured 6.6 mm. Patients were evaluated clinically and radiographically at a mean 57 months follow-up (range 24 to 168 months). The mean Constant score increased from 48.4 points preoperatively to 67.6 points postoperatively (p < 0.0001). Eighty-seven percent of patients were satisfied or very satisfied with the result. Nine patients underwent an additional surgical procedure (three for attempt at rotator cuff repair and six for reverse prostheses for cuff tear arthropathy). The acromiohumeral interval decreased by a mean. 1.3 mm during the follow-up period and was associated with longer duration of follow-up (p < 0.0001). Preoperatively, 38% of patients had glenohumeral arthritis; postoperatively, 67% of patients had glenohumeral arthritis. Concomitant acromioplasty was statistically associated with better subjective and objective results only in patients with an acromiohumeral distance greater than 6 mm. Fatty infiltration of the rotator cuff musculature had a negative influence on both the functional and radiographic results (p < 0.0001). Arthroscopic biceps tenotomy in the treatment of rotator cuff tears in selected patients yields good objective improvement and a high degree of patient satisfaction. Despite these improvements, arthroscopic tenotomy does not appear to alter the progressive radiographic changes that occur with long standing rotator cuff tears

Aims: Outcomes for a RSP to treat either a previous operated shoulder (revision procedure) was compared to a primary RSP. Methods: 20 Primary RSP (6M, 14F) for an irreparable rotator cuff tear (IRCT) with glenohumeral arthritis/anterior superior arch deþciency and 31 revision RSP (10M, 21F) (previous rotator or cuff surgery, hemi or total shoulder arthroplasty) were evaluated at an average of 24 months postoperatively. Mean age at the time of RSP was 72.3 for primaries 67.2 for revisions. Assessment with pre- and postoperatively SF-36, SST, ASES scores, physical exam, satisfaction surveys, and radiographs was performed. Results: Primary RSP improvements/Revision RSP improvements were: 9.4 sf-36 PCS/6.3 sf-36 PCS, 1.8 SST/1.6 SST, 31.8 ASES/17.5 ASES (p< 0.05), 49.2 elevation/14.2 elevation (p< 0.05) and 57.8 external rotation/30 external rotation. 71.3% Excellent/good/. 56% Excellent/good (p< 0.05), 21.4% satisfactory/33.3% satisfactory, 7.1% unsatisfactory outcome/9.5% unsatisfactory outcome. Complications only occurred in the revisions including component disassociation, glenoid loosening, recurrent instability, and infection. Conclusion: Primary RSP provides predictable improvements in pain and function with minimal complications. Revision RSP has a higher complication rate and improvements in pain and function are less reliable. Conventional shoulder arthroplasty for patients with IRCT with glenohumeral arthritis/anterior superior arch deþciency has resulted in adequate pain relief but functional improvement has not been predictable. Thus, the initial operative selection for these patients must consider the effect of a failed reconstructive attempt on patient outcomes

Introduction. Pathophysiology of glenohumeral arthritis differs depending upon type of arthritis. Osteoarthritis. Post-traumatic arthritis. Inflammatory arthritis (i.e. RA). Arthritis of instability. Crystalline arthritis (Milwaukee shoulder, cuff tear arthropathy). Avascular necrosis. Natural history as well as response to treatment are both pathology dependent. Soft-tissue involvement. Rotator cuff tear. Soft tissue contracture. Secondary osseous deformity. Regional osteopenia. Glenoid wear (concentric versus eccentric). Humeral collapse. Surgical options. Joint-sparing techniques. Arthroscopic capsular release/ joint debridement/synovectomy. Open debridement, subscapularis lengthening. Open capsular interposition. Osteotomy. Glenoid. Humeral. Cartilage transplantation. Arthrodesis. Resection arthroplasty. Joint replacement. Unconstrained. Hemiarthroplasty. Total shoulder replacement. Constrained. Joint-sparing Techniques. These techniques are only useful in patients with early changes or who are too young and active for joint replacement. Arthroscopic debridement or capsular release. Young patients. Normal joint alignment. Severe asymmetric capsular contracture (i.e. arthritis of instability). Open debridement. Large humeral osteophytes. Subscapularis lengthening. Open capsular interposition. Lateral edge of anterior capsule sutured to posterior labrum. Less severe degrees of contracture, subscapularis must be repaired anatomically. Osteotomy. Only useful in situations where there is abnormal humeral or glenoid alignment. Glenoid – posterior opening wedge for osteoarthritis in combination with posterior glenoid hypoplasia or increased retroversion. Humeral – most useful for post-fracture deformity (i.e. varus of the surgical neck). Cartilage Transplantation. Very early experience and really only attempted in any numbers in the knee. Chondrocyte transplantation very expensive and tedious. Currently, the most popular techniques involve transplanting plugs or cores of articular cartilage, subchondral bone, and cancellous bone. Autograft- harvest from non-weight-bearing or less weight-bearing area the same or different bone. Lateral femoral condyle. Posterolateral humeral head. Allograft. Early attempts limited by chondrocyte viability after harvest. Improved processing techniques have recently improved chondrocyte survival to 60–70%. Offers the desirable option of being able to preoperatively match radii of curvature of implant to donor site. Arthrodesis. Fortunately, rarely indicated. Patients miss the ability to rotate the humerus. Indications. Brachial plexus injury. Combined deltoid and rotator cuff deficiency. Young heavy labourer. Sepsis. Severe bone loss. Requires functional trapezius and serratus anterior. Resectional Arthroplasty (Jones Procedure). Even more rarely indicated than arthrodesis. Function is better if rotator cuff is attached to proximal humerus. Indications. Sepsis. Failed arthroplasty. Combined deltoid and rotator cuff deficiency. Conclusions. Hemiarthroplasty or total shoulder replacement with unconstrained implants is the surgical treatment of choice in the vast majority of patients with glenohumeral arthritis. Joint-sparing procedures are indicated in young patients with early, less extensive changes. Arthrodesis and resection arthroplasty are rarely indicated, except under unusual circumstances of soft-tissue deficiency, nerve injury, or sepsis. Cartilage transplantation shows promise in very select patients