Abstract Purpose This study reports the long‐term post‐operative clinical outcomes after arthroscopic posterior bone block augmentation with posterior capsular repair. Methods Eighteen shoulders (13 patients) with unidirectional posterior shoulder instability were treated with an arthroscopic posterior bone block augmentation and posterior capsular repair in 2011 and 2013 in a single specialized orthopaedic clinic. These patients were invited to participate in a clinical and radiological follow‐up examination to receive long‐term results regarding clinical outcomes, instability, and development of osteoarthritis (OA). Results From the initial study group, 13 patients (18 shoulders) could be obtained for a follow‐up examination. The mean follow‐up period was 111 months. At the final follow‐up, two patients (two shoulders) reported recurrent subluxations with a positive apprehension sign. No redislocation was reported. Screw fixation was still in place in seven patients (38.9%). Overall, good clinical outcomes were achieved among Constant–Murley score (77.6 ± 16; p = 0.55), Rowe score (67.5 ± 22.1; p = 0.34), Walch–Duplay score (58.3 ± 28.2) and Western Ontario Shoulder Index (40.4 ± 23.3%; p = 0.96), showing insignificant changes compared with the 2‐year results. Three shoulders developed severe OA (Samilson and Prieto III). No patient required arthroplasty. Conclusion Arthroscopic posterior bone block augmentation with posterior capsular repair represents a salvage procedure that can achieve long‐term shoulder stability with overall moderate clinical results. Patients have to be informed about the probable need for implant removal and the high risk of OA development, especially in the presence of pre‐existing cartilage damage, beforehand. Level of Evidence Level IV.

Objective Functional posterior shoulder instability (FPSI) (type B1) is a severe type of instability, mainly in teenagers and young adults, that leads to loss of function, pain, and stigmatization among peers. An experimental nonsurgical treatment protocol based on neuromuscular electrical stimulation (NMES) showed very promising early results in the treatment of FPSI. The hypothesis of this study was that NMES-enhanced physical therapy leads to better outcomes than physical therapy alone as the current gold standard of treatment in patients with FPSI. Methods In this multicenter randomized controlled trial, patients with FPSI were randomly allocated in a 1:1 ratio to either 6 weeks of physical therapy or 6 weeks of physical therapy with simultaneous motion-triggered NMES. Baseline scores as well as outcome scores at 6 weeks, 3 months, 6 months, and 12 months after the intervention were obtained. The predefined primary outcome of this trial was the Western Ontario Shoulder Instability Index (WOSI) at the 3-month time point. Results Forty-nine patients were randomized and eligible for the trial. The group that received physical therapy with simultaneous motion-triggered NMES showed a significantly better main outcome measurement in terms of the 3-month WOSI score (64% [SD = 16%] vs 51% [SD = 24%]). Two-thirds of the patients from the physical therapist group crossed over to the group that received physical therapy with simultaneous motion-triggered NMES due to dissatisfaction after the 3-month follow-up and showed a significant increase in their WOSI score from 49% [SD = 8%] to 67% [SD = 24%]. The frequency of instability episodes showed a significant improvement in the group that received physical therapy with simultaneous motion-triggered NMES at the 3-month follow-up and beyond, while in the physical therapist group, no significant difference was observed. Conclusion The current study shows that NMES-enhanced physical therapy led to statistically significant and clinically relevant improvement in outcomes in the treatment of FPSI compared to conventional physical therapy alone—from which even patients with prior unsatisfactory results after conventional physical therapy can benefit. Impact Based on the results of this study, NMES-enhanced physical therapy is an effective new treatment option for FPSI, a severe type of shoulder instability. NMES-enhanced physical therapy should be preferred over conventional physical therapy for the treatment of patients with FPSI.

The goal of this study was to compare the Shoulder Pacemaker to the current gold-standard in treatment of functional posterior shoulder instability.

Traumatic posterior shoulder joint instability can be associated with a bony defect in the area of the posterior glenoid. For bony defects larger than 11% of the glenoid surface, a 10-fold increased rate of recurrent dislocation after soft-tissue posterior shoulder stabilization alone was observed. This defect size should therefore be classified as critical or in need of care in terms of bony augmentation. The available studies on posterior bone block augmentation primarily involve arthroscopic techniques with screw fixation. With anatomical placement of the bone block in the sense of complementary coverage of the bone defect, the surgical technique shows mostly good results regarding restoration of shoulder stability. However, there were frequent problems due to the implant material that had been introduced, which often had to be removed after remodeling or partial resorption of the bone graft. Inconsistent and sometimes insufficient results were reported when the technique was extended to other indication areas (soft tissue insufficiency, functional instability) and when the bone graft was placed extra-anatomically. Furthermore, existing glenoid dysplasia, incipient omarthrosis, and decentering of the humeral head negatively influenced the results. A strict indication and an implant-free technical implementation are therefore recommended.

Die traumatisch bedingte posteriore Schultergelenkinstabilität kann mit knöchernen Defekten im Bereich des posterioren Glenoids einhergehen. Für Knochendefekte mit einer Größe von > 11

Background: Retears after rotator cuff repair (RCR) have been associated with poor clinical results. Meaningful data regarding the role of arthroscopic revision RCR are sparse thus far. Purpose/Hypothesis: To investigate results after arthroscopic revision RCR. We hypothesized that (1) arthroscopic revision RCR would lead to improved outcomes, (2) the clinical results would be dependent on tendon integrity and (3) tear pattern, tendon involvement, and repair technique would influence clinical and structural results. Study Design: Case series; Level of evidence 4. Methods: During a 40-month period, 100 patients who underwent arthroscopic revision RCR were prospectively enrolled in this multicenter study. Outcomes were evaluated preoperatively, at 6 months (6M), and at 24 months (24M) using the Constant score (CS), the Oxford Shoulder Score (OSS), and the Subjective Shoulder Value (SSV). Tendon integrity at 2 years was analyzed using magnetic resonance imaging. A total of 13 patients (13%) were lost to follow-up, and 14 patients (14%) had a symptomatic retear before the 24M follow-up. Results: All clinical scores improved significantly during the study period (CS: preoperative, 44 ± 16; 6M, 58 ± 22; 24M, 69 ± 19 points; OSS: preoperative, 27 ± 8; 6M, 36 ± 11; 24M, 40 ± 9 points; SSV: preoperative, 43% ± 18%; 6M, 66% ± 24%; 24M, 75% ± 22%) ( P < .01). At 2 years, a retear rate of 51.8% (43/83) and a surgical revision rate of 12.6% (11/87) were observed. Mean full-thickness tear size decreased from 5.00 ± 1.61 cm2 to 3.25 ± 1.92 cm2 ( P = .041). Although the Sugaya score improved from 4.5 ± 0.9 to 3.7 ± 1.4 ( P = .043), tendon integrity did not correlate with better outcome scores. Previous open RCR, involvement of the subscapularis, chondral lesions of Outerbridge grade ≥2, and medial cuff failure were correlated with poorer SSV scores at 2 years ( P≤ .047). Patients with traumatic retears had better CS and OSS scores at 2 years ( P≤ .039). Conclusion: Although arthroscopic revision RCR improved shoulder function, retears were frequent but usually smaller. Patients with retears, however, did not necessarily have poorer shoulder function. Patient satisfaction at 2 years was lower when primary open RCR was performed, when a subscapularis tear or osteoarthritis was present, and when the rotator cuff retear was located at the musculotendinous junction. Patients with traumatic retears showed better functional improvement after revision.

Background Posterior shoulder instability is caused by structural or functional defects. While the former are mostly treated surgically, physiotherapy is considered the treatment of choice in functional shoulder instability. However, it often has limited success unless very specific and intensive training programs are applied by trained experts. Currently, there is no consensus on the treatment of functional posterior shoulder instability. Objective To improve treatment of this pathology, a standardized treatment recommendation is required to serve as a guideline for physiotherapy. The aim of this study was to establish expert consensus for treatment recommendations for functional posterior shoulder instability. Design The Delphi survey technique was employed. Methods A standardized training program for treatment of functional posterior shoulder instability was developed by a local expert committee. Two rounds of an online Delphi survey were then conducted. The panel of the Delphi survey comprised nine leading scientific experts in the field of functional shoulder instability who treat patients with shoulder-related problems conservatively and operatively. Results The response rate was 100% and there were no dropouts. The final program consists of three groups of exercises with increasing difficulty. The exercises are mostly easy to perform and focus on the scapula-retracting muscles and the muscles responsible for external rotation of the shoulder. The treatment program should be executed under the supervision of a therapist at the beginning and later may be performed by the patients themselves. Conclusion Consensus on a new exercise guideline dedicated to the treatment of functional posterior shoulder instability was achieved. This guideline should not only help to treat this challenging pathology but also provide a starting point for further scientific research and ongoing improvement.

Biological factors such as TGF–β3 are possible supporters of the healing process in chronic rotator cuff tears. In the present study, electrospun chitosan coated polycaprolacton (CS–g–PCL) fibre scaffolds were loaded with TGF–β3 and their effect on tendon healing was compared biomechanically and histologically to unloaded fibre scaffolds in a chronic tendon defect rat model. The biomechanical analysis revealed that tendon–bone constructs with unloaded scaffolds had significantly lower values for maximum force compared to native tendons. Tendon-bone constructs with TGF–β3-loaded fibre scaffolds showed only slightly lower values. In histological evaluation minor differences could be observed. Both groups showed advanced fibre scaffold degradation driven partly by foreign body giant cell accumulation and high cellular numbers in the reconstructed area. Normal levels of neutrophils indicate that present mast cells mediated rather phagocytosis than inflammation. Fibrosis as sign of foreign body encapsulation and scar formation was only minorly present. In conclusion, TGF–β3-loading of electrospun PCL fibre scaffolds resulted in more robust constructs without causing significant advantages on a cellular level. A deeper investigation with special focus on macrophages and foreign body giant cells interactions is one of the major foci in further investigations.

Bei einem 24-jährigen Kampfsportler zeigte sich eine traumatische Ruptur der Sehne des M. latissimus dorsi. Klinisch war die Innenrotation gegen Widerstand bei 90° abduziertem Arm abgeschwächt und ein Pseudotumor in der Axilla palpabel. Magnetresonanztomographisch zeigte sich eine 5 cm retrahierte Sehne des M. latissimus dorsi. Die Exposition und Mobilisation des Sehnenstumpfes erfolgte über einen axillären Zugang und die Refixation über einen subpektoralen Zugang. Die Sehne wurde mittels Fadenankern am Humerus refixiert. Postoperativ erfolgte eine kurzfristige Immobilisation und anschließend schrittweiser Freigabe der Beweglichkeit.

In orthopaedic medicine, connective tissues are often affected by traumatic or degenerative injuries, and surgical intervention is required. Rotator cuff tears are a common cause of shoulder pain and disability among adults. The development of graft materials for bridging the gap between tendon and bone after chronic rotator cuff tears is essentially required. The limiting factor for the clinical success of a tissue engineering construct is a fast and complete vascularization of the construct. Otherwise, immigrating cells are not able to survive for a longer period of time, resulting in the failure of the graft material. The femur chamber allows the observation of microhaemodynamic parameters inside implants located in close vicinity to the femur in repeated measurements in vivo. We compared a porous polymer patch (a commercially available porous polyurethane-based scaffold from Biomerix™) with electrospun polycaprolactone (PCL) fibre mats and chitosan (CS)-graft-PCL modified electrospun PCL (CS-g-PCL) fibre mats in vivo. By means of intravital fluorescence microscopy, microhaemodynamic parameters were analysed repetitively over 20 days at intervals of 3 to 4 days. CS-g-PCL modified fibre mats showed a significantly increased vascularization at Day 10 compared with Day 6 and at Day 14 compared with the porous polymer patch and the unmodified PCL fibre mats at the same day. These results could be verified by histology. In conclusion, a clear improvement in terms of vascularization and biocompatibility is achieved by graft-copolymer modification compared with the unmodified material.

BACKGROUND:Numerous factors determine stability of reverse total shoulder arthroplasty. The effect of the conjoint tendon in relation to stability remains unknown. In this biomechanical study, we evaluated the influence of the conjoint tendon on the anterior stability of reverse total shoulder arthroplasty with a hemispherical glenosphere and a glenosphere with 9 mm lateralisation. METHODS:A reverse total shoulder arthroplasty was implanted in 6 human cadaveric shoulders. The anterior stability was evaluated using a shoulder simulator. Two conditions, intact and dissected conjoint tendon, and 2 component configurations, a hemispherical glenosphere and a glenosphere with 9 mm lateralisation, were tested in each specimen. Testing of anterior stability was performed in 30° and 60° of abduction, with 0° and 30° of external rotation in the glenohumeral joint. FINDINGS:The conjoint tendon showed a significant influence on the anterior stability with a hemispherical glenosphere in 30° and 60° with neutral rotation (p = 0.028) as well as 30° abduction with 30° (p = 0.028) external rotation. The 9 mm lateralised glenosphere stabilized significantly reverse total shoulder arthroplasty with resected conjoint tendon compared to the hemispherical glenosphere with resected conjoint tendon (p = 0.028). INTERPRETATION:In a biomechanical setting the conjoint tendon has a stabilizing influence on the anterior stability of the reverse total shoulder arthroplasty with a hemispherical glenosphere in an abducted arm position, but this stabilizing effect was not seen with the lateralised glenosphere. The single influence of the lateralisation of the glenosphere on anterior stability was shown in cases of resected conjoint tendon.

Acute and chronic rotator cuff tears remain challenging for therapy. A wide range of therapeutic approaches were developed but re-tears and postoperative complications occur regularly. Especially in elderly people, the natural regeneration processes are decelerated, and graft materials are often necessary to stabilize the tendon-to-bone attachment and to improve the healing process. We here investigated in a small animal model a newly developed electrospun polycaprolactone fiber implant coated with a chitosan-polycaprolactone graft copolymer and compared these implants biomechanically and histologically with either a commercially available porous polyurethane implant (Biomerix 3D Scaffold) or suture-fixed tendons. Fifty-one rats were divided into three groups of 17 animals each. In the first surgery, the left infraspinatus tendons of all rats were detached, and the animals recovered for 4 weeks. In the second surgery, the tendons were fixed with suture material only (suture-fixed group; n = 17), whereas in the two experimental groups, the tendons were fixed with suture material and the polyurethane implant (Biomerix scaffold group; n = 17) or the modified electrospun polycaprolactone fiber implant (CS-g-PCL scaffold group; n=17), respectively. The unaffected right infraspinatus tendons were used as native controls. After a recovery of 8 weeks, all animals were clinically inconspicuous. In 12 animals of each group, repaired entheses were biomechanically tested for force at failure, stiffness, and modulus of elasticity, and in five animals, repaired entheses were analyzed histologically. Biomechanically, all parameters did not differ statistically significant between both implant groups, and the entheses failed typically at the surgical site. However, with respect to the force at failure, the median values of the two implant groups were smaller than the median value of the suture-fixed group. Histologically, the modified polycaprolactone fiber implant showed no acute inflammation processes, a good infiltration with cells, ingrowth of blood vessels and tendinous tissue, and a normal fibrous ensheathment. Further improvement of the implant material could be achieved by additional implementation of drug delivery systems. Therewith, the used CS-g-PCL fiber mat is a promising basic material to reach the goal of a clinically usable graft for rotator cuff tear repair.

Die Therapie der Omarthrose stellt bei jüngeren Patienten mit einem hohen Aktivitätsanspruch eine große Herausforderung dar, da bei diesen Patienten die endoprothetische Versorgung häufig unbefriedigende Ergebnisse bei begrenzten Standzeiten erzielt.

Die posteriore Schulterinstabilität besitzt eine deutlich geringe Inzidenz als die anteriore Schulterinstabilität. Sie weist ein weites Spektrum an klinischer Symptomausprägung auf. Zudem fehlt bei der Mehrheit der Patienten anamnestisch eine traumatische Erstluxation. Neben der ausführlichen Anamnese ist zur Diagnosefindung die gezielte klinische Untersuchung mithilfe standardisierter Provokationstests wichtig. Zum Nachweis einer strukturellen posterioren Kapsel-Labrum-Läsion sollte bei chronischen Verläufen eine Magnetresonanztomographie mit intraartikulär appliziertem Kontrastmittel durchgeführt werden. Relevante knöcherne Defekte am Humeruskopf (reverse Hill-Sachs-Läsion) sind häufig, während kritische posteriore Defekte des Glenoids relativ selten sind. Beide Läsionen sollten mithilfe der 3D-Computertomographie quantifiziert werden. Die Wahl des therapeutischen Vorgehens orientiert sich am zugrunde liegenden Defekt. Die konservative Therapie ist bei Patienten mit Skapuladyskinesie, willkürlichen Luxationen und pathologischem „muscle patterning“ als sinnvoll zu betrachten. Bei isolierten Weichteilpathologien werden als Standardtherapie die arthroskopische Labrumrefixation und Kapselraffung angewandt. Bei insuffizienten Weichteilverhältnissen oder kritischem posteriorem Glenoiddefekt ist der knöcherne Glenoidaufbau mithilfe des Beckenkammspans die Therapie der Wahl.

In the current study the clinical outcome of an arthroscopic posterior bone block augmentation in combination with a posterior capsular repair was investigated.