Deltoid Muscle Tension Alterations Post Reverse Shoulder Arthroplasty: An Investigation Using Shear Wave Elastography.

INTRODUCTION: This study aimed to evaluate the utility of shear wave elastography (SWE) in assessing changes in deltoid muscle properties following reverse shoulder arthroplasty (RSA). METHODS: Our cohort consisted of 18 patients who underwent RSA due to various conditions, including osteoarthritis, cuff arthropathy, and irreducible proximal humeral fractures. Pre- and postoperative muscle elasticity and stiffness were measured using SWE and were compared with functional outcomes and radiological parameters. RESULTS: Our results showed significant changes in deltoid muscle elasticity after RSA, particularly in the anterior and middle portions. However, these alterations were not correlated with postoperative functional outcomes or specific radiological parameters. The study also underscored the potential of SWE for future applications, including the preoperative assessment of deltoid function, postoperative monitoring, and intraoperative use for optimal component positioning during RSA. CONCLUSION: Further research, involving larger, more homogeneous patient cohorts is needed to confirm these findings and to explore the potential influence of these changes on the biomechanical design of implants and prosthesis positioning in RSA.

Anterior deltoid muscle tension quantified with shear wave ultrasound elastography correlates with pain level after reverse shoulder arthroplasty.

INTRODUCTION: Reverse shoulder arthroplasty (RSA) leads to medialization and distalization of the centre of rotation of the shoulder joint resulting in lengthening of the deltoid muscle. Shear wave ultrasound elastography (SWE) is a reliable method for quantifying tissue stiffness. The purpose of this study was to analyse if deltoid muscle tension after RSA correlates with the patients' pain level. We hypothesized that higher deltoid muscle tension would be associated with increased pain. MATERIAL AND METHODS: Eighteen patients treated with RSA were included. Constant score (CS) and pain level on the visual analogue scale (VAS) were analysed and SWE was performed on both shoulders. All three regions of the deltoid muscle were examined in resting position and under standardized isometric loading. RESULTS: Average patient age was 76 (range 64-84) years and average follow-up was 15 months (range 4-48). The average CS was 66 points (range 35-89) and the average pain level on the VAS was 1.8 (range 0.5-4.7). SWE revealed statistically significant higher muscle tension in the anterior and middle deltoid muscle region in patients after RSA compared to the contralateral non-operated side. There was a statistically significant correlation between pain level and anterior deltoid muscle tension. CONCLUSION: SWE revealed increased tension in the anterior and middle portion of the deltoid muscle after RSA in a clinical setting. Increased tension of the anterior deltoid muscle portion significantly correlated with an increased pain level. SWE is a powerful, cost-effective, quick, dynamic, non-invasive, and radiation-free imaging technique to evaluate tissue elasticity in the shoulder with a wide range of applications. LEVEL OF EVIDENCE: Diagnostic study, Level III.

Less than 9.5-mm coracohumeral distance on axial magnetic resonance imaging scans predicts for subscapularis tear.

BACKGROUND: Diagnosis of subscapularis (SSC) tendon lesions on magnetic resonance imaging (MRI) can be challenging. A small coracohumeral distance (CHD) has been associated with SSC tears. This study was designed to define a specific threshold value for CHD to predict SSC tears on axial MRI scans. METHODS: This retrospective study included 172 shoulders of 168 patients who underwent arthroscopic surgery for rotator cuff tear or glenohumeral instability. Diagnostic arthroscopy confirmed an SSC tear in 62 cases (36.0%, test group a), rotator cuff tear tears other than SSC in 71 cases (41.3%, control group b) and glenohumeral instability without any rotator cuff tear in 39 cases (22.7%, zero-sample group c). All patients had a preoperative MRI of the shoulder (1.5T or 3T). Minimum CHD was measured on axial fat-suppressed proton density-, T2-, or T1-weigthed sequences. Receiver operating characteristics analysis was used to determine the threshold value for CHD, and sensitivity and specificity were calculated. RESULTS: CHD measurement had a good interobserver reliability (Intraclass correlation coefficient 0.799). Mean CHD was highly significantly (P < .001) less for test group a (mean 7.3 mm, standard deviation ± 2.2) compared with control group b (mean 11.1 mm, standard deviation ± 2.3) or zero-sample group c (mean 13.6 mm, standard deviation ± 2.9). A threshold value of CHD <9.5 mm had a sensitivity of 83.6% and a specificity of 83.9% to predict SSC tears. CONCLUSION: A CHD <9.5 mm on MRI is predictive of SSC lesions and a valuable tool to diagnose SSC tears.

Infection control and outcome of staged reverse shoulder arthroplasty for the management of shoulder infections.

BACKGROUND: The treatment of septic arthritis, caused by either hematogenous seeding, injections, or surgery, can be challenging. Staged reverse shoulder arthroplasty (RSA) with temporary implantation of an antibiotic-loaded spacer is widely accepted but still discussed controversially. This study investigated the shoulder-specific bacterial spectrum, infection control rate, functional outcome, and infection-free survival rate after staged RSA in the mid- to long-term follow-up. It was hypothesized that staged RSA would show a high infection-free survival rate. METHODS: A total of 39 patients treated with staged RSA for primary septic arthritis (n = 8), secondary infection (n = 8), or periprosthetic infection (n = 23) were retrospectively included. The infection control rate was calculated based on cultures taken intraoperatively at spacer removal and RSA implantation. Infection-free survival was defined as no revision due to infection. The minimum follow-up period for functional outcome assessment was 2 years (n = 14; mean, 76 months; range, 31-128 months). RESULTS: Cutibacterium (26%) and coagulase-negative staphylococci (23%) were the predominant pathogens. The infection control rate was 90%. The cumulative infection-free survival rate was 91% after 128 months. Follow-up examinations showed a mean Constant score of 48 (range, 7-85), a mean QuickDASH (short version of Disabilities of the Arm, Shoulder and Hand questionnaire) score of 40.0 (range, 11.4-93.3), and a mean pain score of 1.6 (range, 0-7). CONCLUSION: Staged RSA implantation was confirmed to be a reliable treatment option for primary, secondary, and periprosthetic infections of the shoulder. The infection control rate and infection-free survival rate are satisfactory. However, patients and surgeons must be aware of functional impairment even after successful treatment of infections.

Tendon-derived stem cells from the long head of the biceps tendon: Inflammation does not affect the regenerative potential.

OBJECTIVES: The long head of the biceps (LHB) is often resected in shoulder surgery and could therefore serve as a cell source for tissue engineering approaches in the shoulder. However, whether it represents a suitable cell source for regenerative approaches, both in the inflamed and non-inflamed states, remains unclear. In the present study, inflamed and native human LHBs were comparatively characterized for features of regeneration. METHODS: In total, 22 resected LHB tendons were classified into inflamed samples (n = 11) and non-inflamed samples (n = 11). Proliferation potential and specific marker gene expression of primary LHB-derived cell cultures were analyzed. Multipotentiality, including osteogenic, adipogenic, chondrogenic, and tenogenic differentiation potential of both groups were compared under respective lineage-specific culture conditions. RESULTS: Inflammation does not seem to affect the proliferation rate of the isolated tendon-derived stem cells (TDSCs) and the tenogenic marker gene expression. Cells from both groups showed an equivalent osteogenic, adipogenic, chondrogenic and tenogenic differentiation potential in histology and real-time polymerase chain reaction (RT-PCR) analysis. CONCLUSION: These results suggest that the LHB tendon might be a suitable cell source for regenerative approaches, both in inflamed and non-inflamed states. The LHB with and without tendinitis has been characterized as a novel source of TDSCs, which might facilitate treatment of degeneration and induction of regeneration in shoulder surgery.Cite this article: J. Schmalzl, P. Plumhoff, F. Gilbert, F. Gohlke, C. Konrads, U. Brunner, F. Jakob, R. Ebert, A. F. Steinert. Tendon-derived stem cells from the long head of the biceps tendon: Inflammation does not affect the regenerative potential. Bone Joint Res 2019;8:414-424. DOI: 10.1302/2046-3758.89.BJR-2018-0214.R2.

[Indications and techniques of arthroscopic anterior and lateral acromioplasty]. / Aktuelle Indikationen und Techniken der arthroskopischen anterioren und lateralen Akromioplastik.

OBJECTIVE: Arthroscopic anterior acromioplasty (AAAP) for treatment of symptomatic subacromial spur. Arthroscopic lateral acromioplasty (ALAP) to reduce a pathological critical shoulder angle (CSA) and prevent rotator cuff re-tear after reconstruction. INDICATIONS: AAAP is indicated for acromial impingement due to an anterolateral acromial spur with or without bursa-sided rotator cuff lesion. ALAP is indicated concomitant to arthroscopic rotator cuff repair if the CSA is pathologically increased. RELATIVE CONTRAINDICATIONS: Irreparable rotator cuff tear with acetabularization of the acromion due to anterosuperior escape of the humeral head or symptomatic os acromiale can contraindicate for AAAP. Dehiscence of the origin of the deltoid muscle or symptomatic os acromiale can contraindicate for ALAP. SURGICAL TECHNIQUE: To preform AAAP, arthroscopic subacromial decompression is followed by anterolateral resection of an acromion spur or ossification of the coracoacromial ligament. To perform ALAP, arthroscopic subacromial decompression and reconstruction of a rotator cuff-tear is followed by reduction of a pathologically increased CSA by resection of the lateral edge of the acromion. POSTOPERATIVE MANAGEMENT: After isolated AAAP, physiotherapy can be performed without restriction. After AAAP or ALAP combined with rotator cuff repair, immobilization in a brace is recommended. The use of pain medication should be standardized and adapted to individual pain levels.

Hibernoma of the Upper Extremity: Complete Case of a Rare but Benign Soft Tissue Tumor.

Hibernoma is a rare benign lipomatous tumor showing differentiation of brown fatty tissue. To the author's best knowledge, there is no known case of malignant transformation or metastasis. Due to their slow, noninfiltrating growth hibernomas are often an incidental finding in the third or fourth decade of life. The vast majority are located in the thigh, neck, and periscapular region. A diagnostic workup includes ultrasound and contrast-enhanced MRI. Differential diagnosis is benign lipoma, well-differentiated liposarcoma, and rhabdomyoma. An incisional biopsy followed by marginal resection of the tumor is the standard of care, and recurrence after complete resection is not reported. The current paper presents diagnostic and intraoperative findings of a hibernoma of the upper arm and reviews similar reports in the current literature.

Surgical technique and clinical outcome of arthroscopic shoulder stabilization via suture anchors using the lasso-loop stitch.

During arthroscopic Bankart-repair the lasso-loop-stitch can be used. The clinical outcome of this technical modification to a broadly used procedure is not known. We followed-up 24 patients treated with this technique over 30 months. We found an excellent clinical outcome in 96% of all cases. The average Rowe-score was 96.3 points. The mean QuickDash was 2.8 points. Using the lasso-loop-stitch in arthroscopic Bankart-repair is safe and results in very good clinical outcomes. It might lead to an accentuated labral bump and enables secure knot-tying with knot-positioning away from the articular cartilage while avoiding the suture cutting through the tissue.

Arthroskopische Therapie bei spinoglenoidalem Ganglion.

Aims and Indications A paralabral ganglion cyst of the shoulder can cause neuropathy of the inferior branches of the suprascapular nerve. This can lead to atrophy of the infraspinatus muscle. Arthroscopic decompression of the cyst in combination with repair of the associated labrum tear appears to be an effective treatment option. Methods Initially the connection of the cyst to the joint in the area of the posterior rim of the glenoid is identified arthroscopically. Following the decompression of the cyst the labrum tear is repaired to avoid recurrence. The goal is the complete decompression of the ganglion cyst carefully protecting the infraspinatus branch. Concomitant intraarticular pathologies are also addressed. Conclusions In the literature arthroscopic treatment is superior to open surgical treatments. The degree of muscle atrophy at the time of surgery determines the prognosis for functional recovery. There is a lack of long-term outcome studies and publications of larger case series.

Long-term analysis of revision reverse shoulder arthroplasty using cemented long stems.

BACKGROUND: Revision of failed shoulder arthroplasty is often associated with poor results and a high rate of complications. Significant humeral bone loss after removal of long stems poses a considerable surgical challenge. Therefore, the aim of our study was the evaluation of the clinical and radiologic outcome of cemented long-stem humeral components in revision reverse shoulder arthroplasty with a minimum 5 years' follow-up. METHODS: Between June 2001 and June 2009, revision reverse shoulder arthroplasty using long-stem cemented humeral components was performed in 124 patients. Mean age at time of surgery was 69.6 years (range, 42-87 years). Complete clinical and radiographic data were available in 50 patients at a mean of 7 years (range, 5-11.6 years). Postoperative radiographs were evaluated for radiolucent lines, implant migration, fracture, and glenoid notching. RESULTS: The mean Constant score improved from 11.1 points (range, 0-27 points) to 39.5 points (range, 14-73 points) at the latest follow-up. Progressive humeral radiolucency was present in 24 patients, including 6 patients demonstrating complete loosening or progressive distal migration of the humeral stem. We noted an overall of 12 additional complications in 8 patients, necessitating revision surgery in 16. CONCLUSION: The use of long-stem humeral components is a beneficial treatment in revision reverse shoulder arthroplasty. Nevertheless, the high percentage of patients with humeral loosening is concerning. Modular cementless revision stems that are adapted to the distal humeral medullary canal and additional distal screw and cable fixation might enhance durable distal fixation in case of advanced bone loss.

Therapy-resistant septic olecranon bursitis due to Mycobacterium gordonae.

INTRODUCTION: Septic olecranon bursitis due to atypical mycobacteria is rare. An insidious beginning can delay diagnosis and treatment. Antibacterial therapy recommendations are not well-defined for bursitis caused by atypical mycobacteria. We present a rare case of olecranon bursitis caused by Mycobacterium gordonae, reporting our experiences regarding pathogen identification and antibiotic therapy, which differs from regimes used in common septic bursitis mostly caused by staphylococcus aureus. METHODS: A 35-year-old male with bursitis olecrani received open bursectomy. Microbiological culture did not reveal bacteria. Due to wound healing complications revision surgery was performed four weeks postoperatively. Finally, Mycobacterium gordonae was identified by PCR and an antibiogram could be developed. A triple antimicrobial combination therapy with Rifampicin, Clarithromycin, and Ethambutol was administered systemically for 12 months. The patient was followed-up for 24 months. RESULTS: After the second operation with pathogen identification and antibiotic combination therapy the wound healed without any additional complications. At last follow-up 24 months after the first surgery with bursectomy and 23 months after revision surgery with debridement, the patient was still pain free with no significant clinical findings or tenderness to touch at the operation site. Elbow range of motion was full. DISCUSSION: As septic bursitis can be caused by many different and sometimes rare and difficult to identify bacteria, intraoperative probes should be taken and histopathological and microbiological analysis should be conducted, including PCR. In a young man with olecranon bursitis due to Mycobacterium gordonae surgical treatment and an antibiotic combination therapy showed a good clinical outcome after one and two years.

Nail-patella-syndrome in a young patient followed up over 10 years: relevance of the sagittal trochlear septum for patellofemoral pathology.

INTRODUCTION: Nail-patella-syndrome (NPS) is a rare autosomal-dominant inherited disease with pathologies of nails, skeleton, kidneys, and eyes. Linkage to a mutated gene was found. It codes for the transcription-factor LMX1B. In most cases knees are symptomatic. Patients have hypoplastic patellae, which are laterally subluxated. In those individuals a sagittal trochlear fibrous septum was found, dividing the anterior knee-joint-space. In the literature the etiology and clinical significance of this anatomic abnormality is unclear. Based on clinical and intraoperative findings we developed a theory regarding knee pathology in nail-patella-syndrome. Successful treatment via early resection of the septum with sustained good outcome is presented. METHODS: In a symptomatic six-year-old boy with nail-patella-syndrome we resected the fibrous sagittal septum adherent to the trochlea femoris and we balanced the patella via lateral release and medial plication in both knee joints. We analyzed the clinical outcome of this procedure prospectively over 10 years. RESULTS: Postoperatively the hypoplastic patellae stayed centered and stable during further skeletal development. The patient was still pain free with normal range of motion of both operated knee joints after 10 years of follow-up. DISCUSSION: In patients with nail-patella-syndrome and a subluxated or dislocated patella we recommend diagnostics with magnetic-resonance-imaging and early surgical treatment via resection of the trochlear septum and soft-tissue-balancing of the patella. When the septum displaces the patella and prevents physiological articulation of the patella with the trochlea femoris, early septum resection is likely to be important for a good functional outcome and proper development of the patellofemoral joint during growth.

Gorham-Stout syndrome of the shoulder.

INTRODUCTION: Gorham-Stout syndrome (GSS) is a rare but severe subtype of idiopathic osteolysis. There are no guidelines for the treatment of GSS. We analysed different diagnostic and therapeutic regimes and we describe the sucessful treatment of GSS considering individual patient factors. METHODS: We diagnosed three patients with shoulder-specific GSS using clinical, radiological and histopathological examinations. Two out of three patients with similar clinical appearances were treated non-operatively. One patient was treated by reverse shoulder arthroplasty. All patients were analysed retrospectively using clinical and radiological evaluation with a mean follow-up of 42 (range 30-50) months. RESULTS: Two patients had few symptoms of GSS and were treated conservatively. One patient underwent arthroplasty, with a good clinical result. No additional therapy, such as radiation or anti-resorptive medications, was needed for the stable fixation of the prosthesis and the termination of osteolysis. In all patients we found good clinical outcomes with high patient satisfaction. DISCUSSION: GSS is diagnosed after exclusion of infectious, malignant, and systemic disorders. The diagnosis should be supported by clinical, radiological, and histopathological characteristics of patients. Different humoral and cellular changes have been reported in GSS, but lack sufficient supporting evidence. GSS is associated with angiomatous and lymphatic malformations. The changes in GSS and the theories of its pathophysiology may reveal.

No significant difference in clinical outcome and knee stability between patellar tendon and semitendinosus tendon in anterior cruciate ligament reconstruction.

INTRODUCTION: ACL reconstruction with either patellar tendon or semitendinosus tendon autografts are standard procedures. Between these two grafts might be differences in stability, morbidity, or long-term changes. This study investigates outcomes of ACL reconstruction with patellar tendon versus semitendinosus tendon autografts. We hypothesize no significant differences in clinical outcome and knee stability between both groups. METHODS: In a randomized prospective trial, we operated 62 ACL-deficient patients, 45 males and 17 females with a mean age of 29.8 years (min. 18, max. 44). We reconstructed the ligament using either autologous patellar tendon (n = 31) or semitendinosus tendon (n = 31). After 10 years of follow-up, we investigated 47 patients of the study. For evaluation we used a standard clinical examination including one-leg jump test and KT-1000 instrumental translation measure, visual analog pain scale, IKDC subjective knee form, Lysholm score, Tegner activity scale, and standard X-rays of the knee. RESULTS: The data did not show any significant differences between the two groups. Between 5 and 10 years after ACL reconstruction both groups started to develop degenerative arthritic changes, which were detectable in standard radiographs of the knee. At 10-year follow-up mean IKDC for the BPTB group was 1.8 (min. 1, max. 3) and for the ST group it was 2.2 (min 1, max. 4), p = 0.35. Regarding Tegner activity scale after 10 years, the BPTB group showed a mean score of 5.9 (min. 4, max. 9) versus 5.1 (min. 3, max. 7) in the ST group, p = 0.53. For the Lysholm score the BPTB group reached a mean of 92.0 (min. 63, max. 98) and the ST group 91.8 (min. 62, max. 98) points, p = 0.66. There is a tendency for higher donor site morbidity in the BPTB group than in the ST group, p = 0.07. CONCLUSIONS: Both, patellar tendon and semitendinosus tendon are safe autografts for ACL reconstruction. Regarding graft selection, individual patient-dependent factors should be considered. ACL reconstruction cannot fully restore pre-injury status of knee joint function in the majority of cases.

Calcinosis Universalis of the Elbow: A Rare Case with Classical Presentation.

Juvenile Dermatomyositis (JDM) is a rare autoimmune disease in children and adolescents. In these patients calcinosis might be the most characteristic symptom. However there are only few reported cases of intramuscular calcinosis in Dermatomyositis. We report a case of calcinosis universalis (CU) of the elbow in JDM successfully treated with broaching. The patient, a 24-year-old woman, suffered from a long history of JDM. On examination she presented with a fistula lateral to the olecranon and pain of the right elbow joint. Plain X-rays displayed a diffuse pattern of multiple periarticular, subcutaneous, and intramuscular calcifications. The patient underwent surgery for histological and microbiological sampling as well as broaching. Intraoperatively sinus formation and subfascial hard calcium deposition were found. Due to the risk of collateral tissue damage, incomplete broaching was performed. A local infection with Staphylococcus was diagnosed and treated with antibiotics. On six-week and 30-month follow-up the patient was free of pain and had very good function. Calcifications on standard radiographs had almost resolved entirely. This case report gives a summary on calcinosis in Dermatomyositis and adds a new case of recalcitrant CU to the literature. Broaching surgery proved to be a reliable treatment option in symptomatic calcinosis.

Evaluation of the lag sign tests for external rotator function of the shoulder.

Rotator cuff lesions pose a serious clinical challenge. The objective of this study was to verify the biomechanical basis for the lag sign clinical tests for rotator cuff dysfunction. The lag sign tests were simulated in vitro by a sensor-guided robotic simulator configured to reproduce in vivo testing conditions. The ability of the test to isolate supraspinatus and/or infraspinatus dysfunction was investigated from 20 degrees to 90 degrees of scapular plane arm elevation. The test was 100% sensitive for lack of all infraspinatus-teres minor force at all elevations tested (6/6 specimens at 20 degrees, 30 degrees, and 60 degrees elevation; 5/5 at 90 degrees elevation). The test was less sensitive to complete loss of supraspinatus force (1/6 specimens testing positive at 20 degrees, 0/6 at 30 degrees, 3/6 at 60 degrees, and 3/5 at 90 degrees elevation). The results of this biomechanical study suggest the lag sign tests to be highly sensitive only for infraspinatus-teres minor muscle dysfunction.