Endoprothetischer Glenoidersatz mit Rekonstruktionsschale (EPOCA RECO®)

Objective

Alleviation of pain, restoration of function and active range of motion in the shoulder in case of cuff tear arthropathy.

Indications

Cuff tear arthropathy with an insufficient coracoacromial arch and salvage operation of failed hemiprosthesis or reverse shoulder prosthesis.

Contraindications

Active or chronic infections. Lesions of the plexus. Insufficiency of deltoid muscle or subscapularis muscle. Neurologic diseases. Young active patients.

Surgical Technique

Deltopectoral approach. Resection of the humeral head and removal of the failed implant, respectively. Periarticular arthrolysis with preservation of neurovascular structures. Exposure of the glenoid and three-point fixation of the reconstruction socket (EPOCA RECO^®) at the glenoid, the acromion and the coracoid process. Cemented fixation of the polyethylene inlay. Cemented or cementless implantation of the humeral stem in 25° retroversion related to the long axis of the forearm. Reconstruction of the subscapularis muscle.

Postoperative Management

Bedding of the arm in a Gilchrist brace. Passive and active- assisted exercises including continuous passive motion.

Results

From 2002 to 2007, a total of 35 reconstruction sockets (EPOCA RECO^®) were implanted in 34 patients (six men, 28 women – one bilateral implantation was performed at an interval of 8 months in a female patient). Five EPOCA RECO^® implants had to be removed due to major complications. Three patients died, another three patients refused the follow-up examination. The remaining 23 patients (three men, 20 women, average age at the time of surgery 76 years [64–88 years]) were examined 2 years (4–60 months) postoperatively. The preoperative gender-related Constant Score was 21 and improved significantly (p < 0.001) to 58 postoperatively. The pain was significantly reduced. Range of motion for active elevation, internal and external rotation was improved (preoperatively/ postoperatively): elevation 37.2°/65°; internal rotation 14.8%/50%; external rotation 11.3%/47.5%. All patients would undergo the operation again. Overall, there were five major and two minor complications (complication rate 20%).     

Biceps Detachment Decreases Joint Damage in a Rotator Cuff Tear Rat Model

Background

Pathology in the long head of the biceps tendon often occurs in patients with rotator cuff tears. Arthroscopic tenotomy is the most common treatment. However, the role of the long head of the biceps at the shoulder and the consequences of surgical detachment on the remaining shoulder structures remain unknown.

Questions/purposes

We hypothesized that detachment of the long head of the biceps, in the presence of supraspinatus and infraspinatus tears, would decrease shoulder function and decrease mechanical and histologic properties of both the subscapularis tendon and the glenoid articular cartilage.

Methods

We detached the supraspinatus and infraspinatus or the supraspinatus, infraspinatus, and long head of the biceps after 4 weeks of overuse in a rat model. Animals were gradually returned to overuse activity after detachment. At 8 weeks, the subscapularis and glenoid cartilage biomechanical and histologic properties were evaluated and compared.

Results

The group with the supraspinatus, infraspinatus, and long head of the biceps detached had greater medial force and decreased change in propulsion, braking, and vertical force. This group also had an increased upper and lower subscapularis modulus but without any differences in glenoid cartilage modulus. Finally, this group had a significantly lower cell density in both the upper and lower subscapularis tendons, although cartilage histology was not different.

Conclusions

Detachment of the long head of the biceps tendon in the presence of a posterior-superior cuff tear resulted in improved shoulder function and less joint damage in this animal model.

Clinical Relevance

This study provides evidence in an animal model that supports the use of tenotomy for the management of long head of the biceps pathology in the presence of a two-tendon cuff tear. However, long-term clinical trials are required.     

Thirty-six consecutive reverse shoulder arthroplasties in cuff arthropathy: our experience with the anterosuperior approach

Background

The purpose of this study was to analyze the results obtained with the anterosuperior approach with reverse shoulder arthroplasty in terms of functional recovery, pain, and stability of the implant.

Methods

In a cohort of 33 patients with cuff arthropathy, 36 consecutive reverse shoulder arthroplasties were implanted by the same surgeon, using the anterosuperior approach, saving the subscapularis tendon. Those cases were evaluated preoperatively and postoperatively after an average of 37 months on the basis of constant score, X-ray evaluation, and incidence of dislocation.

Results

The constant score increased from 30.4 points preoperatively to 68.3 points. No case of instability was observed.

Conclusions

The good functional results observed with a mean follow-up of approximately 3 years doubtlessly resulted from the correct surgical technique on the glenoid component and the preservation of the anterior wall composed of the subscapularis tendon. Analyzing literature and taking into account our experience, we can say that the anterosuperior approach has certain advantages; this approach takes advantage of the absence of the upper part of the rotator cuff to facilitate exposure of the joint that makes it particularly indicated in cuff arthropathy.     

Reverse Total Shoulder Arthroplasty Improves Function in Cuff Tear Arthropathy

Background  

Early failure due to glenoid loosening with anatomic total shoulder arthroplasty in patients with severe rotator cuff deficiency led to the development of the reverse ball-and-socket shoulder prosthesis. The literature reports improved short-term pain and function scores following modern reverse total shoulder arthroplasty (RTSA) in patients with cuff tear arthropathy (CTA).     

Die metaphys?r verankerte Prothese bei posttraumatischer und prim?rer Omarthrose

Objective

??Bone-saving?? prosthesis designs, e.g., metaphysary fixed implants, are becoming increasingly common in primary arthoplasty of the glenohumeral joints. In primary omarthrosis, this is an accepted procedure. This study shows and evaluates the short-term clinical outcome of posttraumatic omarthrosis patients in comparison with primary omarthrosis patients after ??Eclipse?? implantation.

Patients and methods

From August 2006 to December 2009, a total of 115 metaphysary fixed, stemless shoulder prostheses were implanted for primary omarthrosis (n?=?96) or posttraumatic omarthrosis (n?=?19). All the 115 patients were registered prospectively and examined 6 and 12 months postoperatively. In addition to the radiological studies, the Constant Murley score (CMS) and patient satisfaction were evaluated

Results

Both groups differed significantly in the pre- and postoperative CMS. Implantation of the Eclipse prosthesis led to a highly significant increase in the CMS. There was also a significant increase of the range of motion (ROM) in the posttraumatic group. One year after implantation, 87.5% (n?=?83) of the primary omarthrosis group were ??very satisfied?? or ??satisfied??. In the posttraumatic group, this value was 78.9% (n?=?15). There was 1 early complication (hematoma) and 5 sequelae [2 secondary cuff insufficiencies, 1 luxation with insufficiency of the subscapularis muscle, and 2 glenoid loosenings (2.3 and 3 years after implantation)]. A single complication for the posttraumatic group was reported: one of the two reported secondary cuff insufficiencies.

Conclusion

The implantation of a stemless fixed prosthesis leads in the posttraumatic situation as well as in primary omarthrosis to an identical increase of the CMS. It is a good prosthesis design with rare complications. It is possible to implant the prosthesis independent of the diaphysis of the humerus and malposition of the humeral head.     

Do Less Medialized Reverse Shoulder Prostheses Increase Motion and Reduce Notching?

Background  

Cuff tear arthropathy is the primary indication for total reverse shoulder arthroplasty. In patients with pseudoparalytic shoulders secondary to irreparable rotator cuff tear, reverse shoulder arthroplasty allows restoration of active anterior elevation and painless shoulder. High rates of glenoid notching have also been reported. We designed a new reverse shoulder arthroplasty with a center of rotation more lateral than the Delta prosthesis to address this problem.     

Retroverted glenoid reconstruction using glenoid plate in reverse shoulder arthroplasty

Purpose

The objective of this study is to evaluate the clinical and radiological results of reverse shoulder arthroplasty (RSA) with glenoid plating in a consecutive series of patients affected by cuff tear glenohumeral arthropathy with glenoid retroversion >15°. We hypothesized that autologous humeral head graft may be better stabilized between the baseplate and the native glenoid surface with the use of a glenoid plate.

Methods

Twenty consecutive patients affected by cuff tear arthropathy with glenoid retroversion >15° (B2 or C according to Walch classification) were enrolled in this study. To reconstruct the glenoid, a dedicated plate was used in addition to the standard reverse shoulder baseplate and the glenosphere. Clinical and radiological assessment was performed using constant score (CS), subjective shoulder value (SSV), X-rays and CT scan at 6, 12 and 24 months of follow-up. Healing and resorption of the graft and detection of the glenoid version were assessed.

Results

Sixteen patients were available for final follow-up. The mean preoperative retroversion of the glenoid was 24°, while the post-op was 2° (p = 0.002). At 24 months of follow-up, mean CS and SSV were 61 and 70. Respect to preoperative scores, the results were statistically significant (p < 0.001). The last CT scan revealed: a complete healing of the graft in 100% of cases; graft resorption less than 25% in two patients (12.5%); glenoid retroversion of 4°. A negative statistically significant correlation was found between final CS and preoperative glenoid retroversion (0.039).

Conclusions

The present study reports the favorable outcomes of retroverted glenoid reconstruction with glenoid plates in RSA, an alternative method to address severe glenoid deficiency.

Level of evidence

Level IV, case series with no comparison group.

     

Zementfreier Oberflächenersatz bei Dislokationsarthropathie des Schultergelenks

Background

Only a few reports in the literature describe that total shoulder replacement provides better functional results in dislocation arthropathy than hemiarthroplasty. Nevertheless, the risk of aseptic loosening in young and active patients is high after long-term follow-up. We evaluated the results of cementless humeral head resurfacing in this group.

Methods

We evaluated 29 patients with dislocation arthropathy who had been followed up for a mean of 39 months. The mean age at the time of operation was 43.7±14.7 years. Preoperatively, cuff deficiency was seen in 11 cases.

Results

The mean adjusted Constant score improved from 16.8±15.2% to 78.1±21.9%. Negative prognostic factors turned out to be female sex, age, cuff tears especially of the subscapularis tendon, and previous bone block procedures. Revision was performed in five patients, and two developed painful glenoid erosion which required conversion to total shoulder arthroplasty.

Conclusion

Cementless humeral head replacement is a viable option in the treatment of dislocation arthropathy. Revision can be performed easily since the bone stock has been preserved. On the basis of our data, humeral head replacement in patients <40 years with dislocation arthropathy offers promising short- to midterm results with an acceptable complication rate.     

Short and midterm results of reverse shoulder arthroplasty according to the preoperative etiology

Background

Reverse shoulder arthroplasty (RSA) has shown promising results for cuff tear arthropathy but the indication has been extended to fracture sequelae and revision shoulder arthroplasty with different preconditions. Further, the clinical relevance of inferior scapular notching for different etiologies is uncertain. Our hypothesis was that preoperative etiology as well as the occurrence of scapular notching would significantly influence the clinical outcome.

Methods

We reviewed 76 reverse shoulder arthroplasties for cuff tear arthropathy (45 patients), fracture sequelae (10 patients) and revision arthroplasty (21 patients) retrospectively. The follow-up consisted of 71 patients and the mean follow-up period was 23 months (±14 months). All patients were evaluated postoperatively using the Constant score adjusted for age and gender and the simple shoulder test. A radiological investigation was performed preoperatively and at the time of the final follow-up including the evaluation of scapular notching according to Sirveaux. For further evaluation of scapular notching, patients were separated into three groups according to the inferior glenosphere overlap: negative or no inferior overlap ?6–0 mm), mild overlap (1–4 mm) and pronounced overlap (5–9 mm).

Results

After a mean follow-up of 23 months the average age- and gender-adjusted Constant score (CS) was 77.8 % (±26 %). According to the etiology, patients with cuff tear arthropathy (CTA) showed a higher CS of 83 % compared with patients with fracture sequelae (CS 73 %) and compared with patients who had undergone RSA as a revision for failed shoulder arthroplasty (CS 69 %). The difference was significant comparing the cuff tear arthropathy patients with the revision surgery patients (p = 0.035). Within the group of fracture sequelae, patients with type three sequelae according to the Boileau classification (surgical neck nonunion) had a significantly worse outcome compared with the type four fracture sequelae patients (severe tuberosity dislocation) (CS 57 vs. 87 %, p = 0.01). The overall complication rate was 27 % with 8 % infections and 9 % dislocations. Revision surgery was necessary in 11.5 % with removal or replacement of the implants in 8 %. Inferior scapular notching was detected in 43 % of the patients. These patients had an inferior CS (70 ± 18 %) compared with patients without scapular notching (84 ± 25 %, p = 0.015). The incidence of scapular notching was significantly reduced with an increasing inferior overlap of the glenosphere.

Conclusions

In conclusion, we found the preoperative etiology to influence the clinical results after RSA with superior results given for cuff tear arthropathy and inferior results for revision arthroplasty and fracture sequelae type three. Further, we found a correlation between scapular notching and the clinical outcome. The inferior scapular notching was significantly reduced by an increased inferior glenosphere overlap.

Level of evidence

Level IV, case series, treatment study.     

Arm Squeeze Test: a new clinical test to distinguish neck from shoulder pain

Purpose

Objective of this study is to evaluate the diagnostic values of the Arm Squeeze Test. The test consists in squeezing the middle third of the upper arm.

Methods

1,567 patients were included in this study. Diagnosis of cervical nerve root compression or shoulder disease was clinically formulated and confirmed with imaging before performing test. 350 healthy volunteers were recruited as controls. The test was positive when score on a VAS Scale was 3 points or higher on squeezing the middle third of the upper arm compared to acromioclavicular (AC) joint and anterolateral-subacromial area.

Results

Patients were subdivided as follows: 903 with rotator cuff tear, 155 with shoulder adhesive capsulitis, 101 with AC joint arthropathy, 55 with calcifying tendonitis, and 48 affected by glenohumeral arthritis. The study sample included 305 patients with cervical nerve root compression from C5 to T1 with shoulder radicular pain. The test was positive in 295/305 (96.7 %) of patients with cervical nerve root compression, compared to 35/903 (3.87 %), 3/155 (1.93 %), 0/101 (0 %), 1/55 (1.81 %) and 4/48 (8.33 %) of those with rotator cuff tear, adhesive capsulitis, AC arthropathy, calcifying tendonitis and glenohumeral arthritis, respectively. A positive result was obtained in 14/350 asymptomatic subjects (4 %). If patients with cervical nerve root compression were compared to controls and patients with shoulder diseases, the test had sensitivity of 0.96 and specificity from 0.91 to 1.

Conclusions

The Arm Squeeze Test may be useful to distinguish cervical nerve root compression from shoulder disease in case of doubtful diagnosis. A positive result to this test may lead to cervical etiology of the shoulder pain.     

Prevalence of subscapularis tears and accuracy of shoulder ultrasound in pre-operative diagnosis

Purpose

Subscapularis tears can be difficult to diagnose and their treatment requires advanced arthroscopic skills. The objective of this study was to find the prevalence of subscapularis tears on arthroscopic examination of shoulders with rotator cuff pathology and to determine the accuracy of pre-operative ultrasound in diagnosing these tears.

Method

Ultrasound and intra-operative reports of 236 patients who underwent shoulder arthroscopy for rotator cuff pathology by the senior author at his institution were compared. Prevalence of subscapularis tear was noted and classified using Lafosse classification system. Ultrasound reports and intra-operative findings were compared to determine the accuracy, sensitivity and specificity of ultrasound in detecting subscapularis tears.

Results

The prevalence of subscapularis tears in patients needing rotator cuff repair was found to be 31.4 %. A total of 6.4 % of patients needing a rotator cuff repair had an isolated subscapularis tear. The sensitivity of ultrasound was 39.5 % and specificity 93.1 % in detection of these tears. The overall accuracy of ultrasound was 75.8 %. Sensitivity of ultrasound was low (42.8 %) for smaller (type 1 and 2) tears and higher (79 %) for larger (types 3, 4, 5) tears. The overall positive predictive value of USS was 73.1 % and negative predictive value 76.4 %.

Conclusion

The shoulder surgeon should be skilled in diagnosing and repairing subscapularis tendon tears arthroscopically and cannot completely rely on pre-operative ultrasound scans in ruling out smaller tears as its sensitivity in diagnosing smaller tears is quite low. Unsettling anterior shoulder pain with a normal ultrasound may need further arthroscopic evaluation to rule out missed subscapularis tears.

     

Prospective clinical study of a novel biodegradable sub-acromial spacer in treatment of massive irreparable rotator cuff tears

Purpose

The purposes of this prospective non-randomized study were to confirm the feasibility of the biodegradable sub-acromial spacer (InSpace?) implantation in patients with massive irreparable rotator cuff tear and to determine the safety profile and functional results 3 years post-implantation.

Methods

Twenty patients were implanted with the InSpace? device and assessed up to 3 years of post-implantation. Improvement in shoulder function was assessed using Constant score, while ease of use of the system was recorded by surgeons as were device-related adverse events.

Results

Twenty patients were available for assessment. Implantation was performed arthroscopically in all patients, and a range of deployment time was 2–20 min. The mean total Constant score increased from 33.4 to 65.4 points at 3 years. There was an improvement of 6.4 points in subjective pain score which commenced at 1 week post-operatively and was sustained until 3 years of follow-up. Also activities of daily living and motions commenced improvement by 9.4 and 7.7 points, respectively. Improvement in power was only evident at 18 months of follow-up but was sustained at 3 years.

Conclusions

Arthroscopic deployment of a co-polymer biodegradable spacer (balloon) into the sub-acromial space for an irreparable rotator cuff tear was found to be low-risk and simple procedure associated with improvement in shoulder function and low rate of complications.

Level of evidence

IV; therapeutic case series     

Die inverse Schulterendoprothese zur Behandlung der Defektarthropathie

OBJECTIVE: Total shoulder replacement for restoration of function and for pain relief of damaged glenohumeral joint accompanied by extensive irreparable cuff defect. INDICATIONS: Any painful shoulder arthropathy with insufficient and irreparable rotator cuff, especially primary defect arthropathy, rheumatoid arthritis with extensive rotator cuff defect, arthropathy after reconstruction of rotator cuff, mutilating rheumatoid arthritis, and crystal-induced arthropathy. Relative: failure of primary shoulder replacement in the presence of an irreparable cuff defect. CONTRAINDICATIONS: Structural or neurogenic lesion of deltoid muscle. Advanced glenoid destruction. Relative: age < 65 years. SURGICAL TECHNIQUE: Anterosuperior or deltopectoral approach. Exposure of glenoid. Resection of humeral head at epi-metaphyseal junction. Complete detachment of anterior, inferior, and posterior capsule from glenoid neck. Preparation of glenoid for cement-free fixation of glenoid base plate (metaglène). Preparation of humeral shaft for implantation of humeral component in 0-10 degrees of retroversion. Screwing of glenosphere to base plate. Insertion of cemented or cement-free modular humeral component. RESULTS: Between 10/1997 and 03/2001, a reverse total shoulder arthroplasty was done in 57 patients (14 men, 43 women; average age 70.1 years). Average follow-up time was 18.2 months. 98% of patients would agree to repeat surgery. Average Constant Score adjusted to age and gender was 94%, 97% for patients not having undergone previous surgery. All patients reported complete or almost complete freedom of pain. On the condition that the deltoid muscle was not damaged during previous surgery, a good improvement of power and function could be obtained. All functional parameters were normal for the patient's age with the exception of a slight limitation of internal rotation (average L5). The power of maintained abduction also corresponded in general to age-specific values. Only grade 1 or 2 inferior glenoid notching was observed but never reaching or surpassing the inferior screw (grade 3 or 4); no glenoid base plate loosening.     

Aussagekraft der Magnetresonanztomographie bei der präoperativen Diagnostik von Rotatorenmanschetten- und Labrumläsionen der Schulter

Background

MR imaging is the method of choice in the identification of soft tissue structures. In shoulder injuries, it is widely used for the diagnosis of rotator cuff and labral lesions. In this study, the significance of MR imaging was evaluated by correlating the preoperative imaging with the results from shoulder arthroscopy.

Methods

From 8/2003 to 8/2007, 162 arthroscopic shoulder examinations in 161 patients were performed. In 146 of these patients, MR imaging was performed before surgery. Images in the transverse, paracoronal, and parasagittal planes using T1- and T2-weighting were obtained. The retrospective study included 146 patients (60 women, 86 men, mean age 52 years). MRI was performed after shoulder injury or in the case of unexplainable, persisting shoulder pain because of clinical aspects of the examination. MR imaging is compared with the arthroscopic findings. The χ² test and contingency tables were used for statistical evaluation.

Results

A transmural rotator cuff tear was diagnosed preoperatively by MRI in 76 patients. During shoulder arthroscopy, 82 transmural cuff tears were found. One tear identified by MRI could not be verified by arthroscopy. A total of 7 lesions were not identified preoperatively, which included 4 cases of subscapularis tendon and 1 of the supraspinatus tendon. Thus, sensitivity of MR imaging was 0.90 with a specificity of 0.91. A labral lesion was diagnosed by MRI in 16 patients, while during arthroscopy, 31 labral lesions were found. One MRI lesion could not be confirmed. Except for one lesion, none of the 13 SLAP lesions could be diagnosed by MRI. Thus, the sensitivity of MR imaging was 0.52 and specificity was 0.89.

Discussion

Native MR imaging is a reliable diagnostic procedure for the evaluation of transmural rotator cuff tears. Labral lesions, however, and especially SLAP lesions can not always be identified during routine native MRI. Here special scans, for instance in the ARBER position, or contrast-enhanced techniques should be taken into consideration to improve the correlation to arthroscopic results.     

Anatomical glenoid reconstruction via a J-bone graft for recurrent posttraumatic anterior shoulder dislocation

Objective

To reconstruct the anatomical glenoid shape in cases of osseous glenoid rim defects after recurrent posttraumatic anterior shoulder dislocation to restore stability without severely compromising the range of motion.

Indications

Osseous glenoid defects after recurrent posttraumatic anterior shoulder dislocation. Suitable for primary stabilization as well as for revision surgery in cases previously operated on.

Contraindications

Recurrent anterior shoulder dislocations without glenoid rim defects. Hyperlax shoulders with multidirectional instability. Patients over 60?years of age due to compromised bone quality. Teenage patients due to incomplete apophyseal fusion at the iliac crest.

Surgical technique

The subscapularis tendon and capsule are split. The humeral head is retracted laterally, and the glenoid defect is prepared and abraded with a rasp. A bicortical iliac crest bone block including crest and outer cortex is harvested and molded in a J-shaped manner. To incorporate the graft, a crevice on the glenoid rim is produced using a chisel. The keel is fitted into the preformed crevice with a spiked impactor. The graft??s surface is contoured using a high-speed burr.

Results

A total of 47?shoulders were followed-up after an average of 90?months (range 25?C152?months). The mean Rowe scores were 94.3 for the affected shoulder and 96.8 for the uninjured shoulder. The Constant scores reached 93.5 and 95?points, respectively. Loss of external rotation was 4.4°. In addition, 24?shoulders were followed-up by computed tomography (CT). There were no recurrences, with the exception of one traumatic graft fracture. Of 19?patients with arthropathy at follow-up, 11?already had arthropathy prior to the procedure.     

CT scan evaluation of glenoid component fixation: a prospective study of 27 minimally cemented shoulder arthroplasties

Background

Glenoid component failure is the most common complication of total shoulder arthroplasty. It can be correlated with failure of the component itself to resist wear and deformation, failure of fixation or failure of the glenoid bone. Anchor Peg Glenoid component (Depuy^®) seems to have a higher bone fixation in biomechanical canine model: it is a all-polyethylene, concave component with one circumferentially fluted, central, interference-fit peg and three small cemented peripheral pegs.

Materials and methods

We realized a prospective study of Anchor Peg total shoulder arthroplasty, included 27 patients suffering from primary arthrosis or arthritis, without rotator cuff tear. A clinical and radiographic evaluation was performed at 3 months, 1 and 2 years; a CT scan was made in postoperative and analyzed central peg’s bone integration 1 year later.

Results

Improvement of postoperative Constant score and radiographic good results were correlated with satisfactory subjective results reported by patients. We observed radiolucent lines under glenoid component in 3 cases. Twenty-six CT scans were available at 1 year: it showed complete bone integration around the central peg in 21 cases and partial peripheral bone integration in four cases. Only one patient had any tissue integration around the peg, probably because of his implantation near cortical bone of scapular spine.

Discussion/conclusion

Long-term result of arthroplasty is correlated with glenoid durable fixation to underlying bone: this study shows higher fixation of glenoid component with bone integration of central peg. However, these results will have to be confirmed in a later revision.     

Cuff tear arthropathy is best treated with a reverse total shoulder arthroplasty

Cuff tear arthropathy is the arthritic eroded collapse of the glenohumeral joint with progressive superior humeral migration in the setting of long-standing rotator cuff insufficiency. The ideal management of cuff tear arthropathy remains elusive. Current arthroplasty options include hemiarthroplasty or reverse shoulder arthroplasty. Proper clinical and radiographic evaluation is essential in decision making in order to optimize outcomes. Acromio-humeral distance (AHD), as measured on plain radiographs, as well as fatty degeneration of the rotator cuff muscles on MRI are reliable tools for decision making. AHD < 7 mm correlates well with complete tear of the supraspinatus while AHD < 5 mm indicates infraspinatus involvement with significant muscular atrophy. Hemiarthroplasty remains an option for providing pain relief; however, continued development of superior migration and glenoid erosion remains a concern. The conversion to reverse total shoulder arthroplasty after hemiarthroplasty can be difficult due to glenoid bone loss. Recent literature supports the use of reverse total shoulder arthroplasty over hemiarthroplasty for cuff tear arthropathy with significant differences in functional outcome. Here, we discuss the radiographic evaluation of cuff tear arthropathy and review the treatment options and why we advocate the use of the reverse prosthesis.     

How to deal with glenoid type B2 or C? How to prevent mistakes in implantation of glenoid component?

Background

Although TSA has been shown to significantly yield better outcomes than hemiarthroplasty, glenoid prosthesis loosening remains the most common complication. Inadequate primary fixation enables the glenoid component to move. In primary glenohumeral osteoarthritis (GHOA), glenoid involvement and proper morphology vary considerably. Postero-inferior glenoid hypoplasia could be associated with some degree of osteoarthritis. According to Walch, 24 % of glenoids in GHOA are type B2 or C (excessive posterior retroversion), which increases the challenge for the glenoid component fixation.

Materials and methods

A total of 30 cases of TSR with glenoid type B2 (20 cases) and type C (10 cases) were reviewed. Mean follow-up was 11.2 months. A metal-backed (MB) glenoid component was implanted, with a posterior bone graft reconstruction. Pre- and post-operative clinical evaluation was done using the Constant–Murley score and the SST from Matsen.

Results

There is no glenoid loosening, no joint narrowing and no radiolucent line. There was no bone graft osteolysis. With 4 patients revised (4 conversions from TSR to RSR for 3 instabilities and 1 secondary rotator cuff tear), on the overall 30 patients cohort, Constant score pain increased from 1.6 to 13.4, forward flexion from 92° to 146° and Constant score from 27 (36 %) to 70 (95 %). The statistical difference between pre- and post-operative values is greatly significant.

Conclusion

Although MB prostheses have been noted to have a higher rate of loosening than full-cemented PE, this is not our experience, even in case of glenoid type B2 or C, where the technical challenge is demanding and most of the time a posterior bone graft is necessary.     

Metallosis‐Induced Conversion Shoulder Arthroplasty: A Unique Experience and Literature Review

Background

Total shoulder arthroplasty (TSA) can fail for several reasons, such as component loosening, periprosthetic fracture, instability, infection, soft tissue failure, or joint overstuffing. Severe metallosis without loose glenoid components after TSA may result in the need for revision to reverse TSA.

Case presentation

Four years before the current presentation, an 86-year-old woman suffered from right shoulder pain and swelling. The initial diagnosis was osteoarthritis of the shoulder joint, for which she underwent TSA. Four years later, she complained of shoulder joint pain, swelling, and limited range of motion. On sonography, subscapularis and supraspinatus tendon tears were identified. Plain radiographs and computed tomography (CT) scans showed metallosis around the shoulder joint. Due to the rocking horse mechanism, wear of the upper portion of the glenoid component and bearing caused a foreign-body reaction and severe metallosis around the joint. Due to a massive rotator cuff tear combined with glenoid component wear, the patient eventually underwent reverse TSA (RTSA) and was satisfied with the final results.

Conclusions

Severe metallosis due to glenoid component wear combined with a massive rotator cuff tear in TSA may cause the need for revision to RTSA.