Surgical treatment of fracture sequelae of the proximal humerus according to a pathology-based modification of the Boileau classification results in improved clinical outcome after shoulder arthroplasty.

BACKGROUND: Fracture sequelae of the proximal humerus were classified by Boileau into four types. Since there are pathomorphological differences and specific characteristics within the four types, we have developed a subclassification. For elderly patients, shoulder arthroplasty is mostly recommended. Based on the available literature and clinical trial results, a subclassification could be created that suggests a specific therapy for each subgroup. The aim of this study was to evaluate the endoprosthetic therapy according to the proposed subclassification and to provide an overview of the clinical and radiological results after endoprosthetic treatment of proximal humerus fracture sequelae. METHODS: Patients with fracture sequelae of the proximal humerus who underwent arthroplasty according to the suggestion of the subclassification were included. Minimum time to follow-up was twelve months. General condition and several specific shoulder scores as the Constant-Murley Score (CS) were recorded at the follow-up examination. Complication and revision rates were analyzed. RESULTS: In total, 59 patients (72.6 ± 10.0 years, 47 females, 12 males) were included. Mean follow-up time was 31.3 ± 17.0 months. Reverse shoulder arthroplasty was performed in 49 patients and anatomic shoulder arthroplasty was performed in ten patients. The CS increased by 47.3 points from preoperative (15.0) to postoperative (62.3). Good or very good clinical results were seen in 61% of the patients. Complications were observed in twelve (20%) patients and revision surgery was performed in nine (15%) patients. CONCLUSION: Due to of the variety of fracture sequelae of the proximal humerus, a modification of the Boileau classification seems necessary. This study shows that endoprosthetic treatment for fracture sequelae can significantly improve the shoulder function in elderly patients. Good clinical results can be achieved with a comparatively low revision rate following the treatment suggestions of the proposed subclassification of the Boileau classification. LEVEL OF EVIDENCE IV: Case series.

Correct positioning of the calcar screw leads to superior results in proximal humerus fractures treated with carbon-fibre-reinforced polyetheretherketone plate osteosynthesis with polyaxial locking screws.

BACKGROUND: Plate osteosynthesis with implants made of carbon-fibre-reinforced polyetheretherketone (CFR-PEEK) has recently been introduced for the treatment of fractures of the proximal humerus (PHFs). The advantages of the CFR-PEEK plate are considered to be its radiolucency, its favourable modulus of elasticity, and the polyaxial placement of the screws with high variability of the angle. The primary aim of this study is to investigate the influence of calcar screw positioning on the complication and revision rates after CFR-PEEK plating of PHFs. The secondary aim is to assess its influence on functional outcome. MATERIAL AND METHODS: Patients were identified retrospectively. Minimum follow-up was 12 months. The cohort was divided into two groups depending on the distance of the calcar screw to the calcar (group I: < 12 mm, group II: ≥ 12 mm). The range of motion (ROM), Subjective Shoulder Value Score (SSV) and Constant-Murley Score (CS) were analysed at follow-up examination. Subjective complaints, complications (e.g. humeral head necrosis, varus dislocation) and the revision rate were evaluated. RESULTS: 51 patients (33 female, 18 male) with an average age of 68.6 years were included after a period of 26.6 months (group I: 32 patients, group II: 19 patients). Apart from the gender distribution, no significant differences were seen in the patient characteristics. The outcome scores showed significantly better clinical results in group I: SSV 83.4 vs 71.2, p = 0.007; CS 79.1 vs 67.8, p = 0.013. Complications were seen less frequently in group I (18.8 % vs 47.4 %, p = 0.030). CONCLUSION: This study shows that the positioning of the calcar screw is relevant for CFR-PEEK plate osteosynthesis in PHFs with a good reduction of the fracture. Optimal positioning of the calcar screw close to the calcar (< 12 mm) is associated with a lower rate of complications, resulting in significantly superior functional outcomes. LEVEL OF EVIDENCE: III, retrospective cohort study.

[The shoulder and elbow register of the DVSE-trend monitoring or early warning system? : A literature-based analysis]. / Das Schulter- und Ellenbogenregister der DVSE ­ Trendbeobachtung oder Frühwarnsystem? : Eine literaturbasierte Analyse.

The endoprosthesis register (SEPR) of the D­A-CH Association for Shoulder and Elbow Surgery e. V. (DVSE) collects data on the implantation of shoulder and elbow endoprostheses. The question arises as to whether the data is only used to monitor trends in arthroplasty, or whether it can also be used as an early warning system for risks and possible complications. The existing literature on the SEPR was analyzed and compared with other national endoprosthesis registries. The SEPR of the DVSE enables the collection and analysis of epidemiological data on primary implantation, follow-up and revision in shoulder and elbow endoprosthetics. It is an instrument of quality control and contributes to ensuring the greatest possible patient safety. It is used for the early detection of risks and potential requirements associated with shoulder and elbow arthroplasty.

Functional results and unfavorable events after treatment of proximal humerus fractures using a new locking plate system.

BACKGROUND: Proximal humerus fractures are often treated with a fixed-angle titanium plate osteosynthesis. Recently, plates made of alternative materials such as carbon fibre-reinforced polyetheretherketone (CFR-PEEK) have been introduced. This study presents the postoperative results of patients treated with a CFR-PEEK plate. METHODS: Patients with proximal humerus fractures treated with a CFR-PEEK plate (PEEKPower™ Humeral Fracture Plate (HFP)) were included. In follow-up examination, age and gender adjusted Constant-Murley Score (ACS), Subjective Shoulder Value (SSV), Quick Disabilities of the Arm, Shoulder and Hand Score (QDASH) and pain score (Visual Analog Scale (VAS)) were analyzed. General condition at follow-up was measured by European Quality of Life 5 Dimensions 3 Level Version (EQ-5D-3L). Range of motion was recorded. In addition, radiographs at follow-up, unfavorable events and revision rate were analyzed. RESULTS: In total, 98 patients (66.0 ± 13.2 years, 74 females, 24 males) were reexamined. Mean follow-up was 27.6 ± 13.2 months. There were 15 2-part, 28 3-part and 55 4-part fractures. The functional scores showed good results: SSV 83.3 ± 15.6%, QDASH 13.1 ± 17.0 and ACS 80.4 ± 16.0. A 4-part-fracture, head split component, nonanatomic head shaft reposition and preoperative radiological signs of osteoarthritis were significant negative predictors for poorer clinical scores. Unfavourable events were observed in 27 patients (27.6%). Revision surgery was performed in 8 (8.2%) patients. Risk factors for an unfavourable event were female gender, age of 50 years and older, diabetes, affected dominant hand, 4-part fracture, head split and preoperative radiological signs of osteoarthritis. CONCLUSION: There are several advantages of the CFR-PEEK plate (PEEKPower™ Humeral Fracture Plate (HFP)) such as the polyaxial screw placement and higher stability of locking screws. In summary, the CFR-PEEK plate osteosynthesis is a good alternative with comparable clinical results and some biomechanical advantages. Proximal humerus fractures show good clinical results after treatment with a CFR-PEEK plate. The revision rate and the risk of unfavorable events are not increased compared to conventional titanium plate osteosynthesis. LEVEL OF EVIDENCE: IV.

Treatment of avascular necrosis of the humeral head - Postoperative results and a proposed modification of the classification.

BACKGROUND: Avascular necrosis of the humeral head after proximal humeral fracture i.e. type 1 fracture sequelae (FS) according to the Boileau classification is a rare, often painful condition and treatment still remains a challenge. This study evaluates the treatment of FS type 1 with anatomic and reverse shoulder arthroplasty and a new subclassification is proposed. METHODS: This single-center, retrospective, comparative study, included all consecutive patients with a proximal humeral FS type 1 treated surgically in a four-year period. All patients were classified according to the proposed 3 different subtypes. Constant score (CS), Quick DASH score, subjective shoulder value (SSV) as well as revision and complication rate were analyzed. In the preoperative radiographs the acromio-humeral interval (AHI) and greater tuberosity resorption were examined. RESULTS: Of 27 with a FS type 1, 17 patients (63%) with a mean age of 64 ± 11 years were available for follow-up at 24 ± 10 months. 7 patients were treated with anatomic and 10 with reverse shoulder arthroplasty. CS improved significantly from 16 ± 7 points to 61 ± 19 points (p < 0.0001). At final follow-up the mean Quick DASH Score was 21 ± 21 and the mean SSV was 73 ± 21 points. The mean preoperative AHI was 9 ± 3 mm, however, 8 cases presented an AHI < 7 mm. 4 cases had complete greater tuberosity resorption. The complication and revision rate was 19%; implant survival was 88%. CONCLUSION: By using the adequate surgical technique good clinical short-term results with a relatively low complication rate can be achieved in FS type 1. The Boileau classification should be extended for fracture sequelae type 1 and the general recommendation for treatment with hemiarthroplasty or total shoulder arthroplasty has to be relativized. Special attention should be paid to a decreased AHI and/or resorption of the greater tuberosity as indirect signs for dysfunction of the rotator cuff. To facilitate the choice of the adequate prosthetic treatment method the suggested subclassification system should be applied.

Locked fracture dislocations of the proximal humerus: postoperative results and a proposed modification of the classification.

BACKGROUND: Locked dislocations of the glenohumeral joint are disabling and often painful conditions and the treatment is challenging. This study evaluates the functional outcome and the different prosthetic treatment options for chronic locked dislocations of the glenohumeral joint and a subclassification is proposed. METHODS: In this single-center retrospective case series, all patients with a chronic locked dislocation treated surgically during a four-year period were analyzed. Constant score (CS), Quick Disabilities of Shoulder and Hand Score (DASH), patient satisfaction (subjective shoulder value (SSV)), revision rate and glenoid notching were analyzed. RESULTS: 26 patients presented a chronic locked dislocation of the glenohumeral joint. 16 patients (62%) with a mean age of 75 [61-83] years were available for follow-up at 24 ± 18 months. CS improved significantly from 10 ± 6 points to 58 ± 21 points (p < 0.0001). At the final follow-up, the mean DASH was 27 ± 23 and the mean SSV was 58 ± 23 points. The complication rate was 19% and the revision rate was 6%; implant survival was 94%. Scapular notching occurred in 2 (13%) cases (all grade 1). CONCLUSION: With good preoperative planning and by using the adequate surgical technique, good clinical short-term results with a low revision rate can be achieved. The authors suggest extending the Boileau classification for fracture sequelae type 2 and recommend using a modified classification to facilitate the choice of treatment as the suggested classification system includes locked posterior and anterior dislocations with and without glenoid bone loss. LEVEL OF EVIDENCE: IV.

GIRD syndrome in male handball and volleyball players: Is the decrease of total range of motion the turning point to pathology?

BACKGROUND: Adaptations in glenohumeral range of motion may affect overhead athletes and lead to shoulder pathologies. OBJECTIVE: The purpose of this study was to evaluate glenohumeral internal rotation deficit (GIRD) and postero-superior impingement among male handball and volleyball players and the relationship between these pathologies and training level (amateur vs. professional), position (attack vs. no attack), experience (> 5 years vs. < 5 years) and sports. METHODS: Sixty-seven handball players and 67 volleyball players with a mean age of 25 [± 5] years were included. The range of motion including external and internal rotation in 90∘ abduction of the dominant and non-dominant shoulder was measured of each examined athlete. Visual analogue scale, disabilities of the shoulder and hand score, constant score and subjective shoulder value were recorded. The athletes were examined for postero-superior impingement and abduction force was measured with an isokinetic dynamometer. RESULTS: Internal rotation was significantly lower and external rotation was significantly greater in the dominant arm for both sports. 72% presented with GIRD. GIRD was more prevalent in athletes active for > 5 years (odds ratio (OR) 3), in those training > 3 times per week (OR 1.4) and in handball players (OR 2.7). 24% presented with postero-superior impingement. Players active for > 5 years (OR 1.22), professionals (OR 1.14), volleyball players (OR 1.19), offensive players (OR 2.2) and athletes with GIRD > 10∘ (OR 1.5) showed a higher prevalence of postero-superior impingement. CONCLUSION: GIRD is a common phenomenon in handball and volleyball players. Offensive players are frequently suffering from postero-superior impingement. GIRD > 10∘ leads in nearly 75% of the athletes to a decrease of total range of motion and a high rate of postero-superior impingement. Thus, a decreased range of motion seems to be the turning point from adaptation to pathology. Therefore, regular controls of range of motion and countermeasures by means of stretching the posterior shoulder joint should be integrated in the training content.

Tensioning device increases biomechanical stability of tuberosity fixation technique with cerclage sutures in reverse shoulder arthroplasty for fracture.

BACKGROUND: Complex proximal humeral fractures in elderly patients are increasingly treated with primary reverse total shoulder arthroplasty. Many surgeons use cerclage sutures for tuberosity fixation in reverse total shoulder arthroplasty for proximal humeral fractures. In this study, we hypothesized that sutures fixated with a tensioning device would achieve higher initial fixation stability of the tuberosities compared with manually knotted cerclage sutures in a biomechanical model. METHODS: A 4-part fracture was created in 7-paired human cadaver proximal humeri. The tuberosities were reduced anatomically and fixed with 3 cerclage sutures in a standardized technique. Tightening was performed either manually (n = 7) or with a cerclage tensioning device with 50 Newton meter (N m) (n = 7). The humeri were placed in a custom-made test setup enabling internal and external rotation. Cyclic loading with gradually increasing load was applied with a material testing machine starting with 20 N m and increasing by 5 N m after each 100th cycle until failure (>15° rotation of the tuberosities). Motion of the tuberosities was measured with a 3-dimensional camera system. RESULTS: Overall, the knot group reached 1040 ± 152 cycles, and the device group reached 1820 ± 719 cycles (P = .035). Major fragment motion was detected in the humeral shaft axis and in the distal divergence of the tuberosities. After 900 cycles, the knot group showed increased rotation of both lesser and greater tuberosities in all 3 axes around the humeral shaft compared with the device group. CONCLUSION: Biomechanical stability of the reattached tuberosities is significantly increased, and rotational movement of the tuberosities is decreased after tightening of the applied cerclage sutures with a tensioning device compared with manual knotting. However, transferability of these promising biomechanical results and their clinical relevance have to be verified with clinical studies.

Proximal humeral fracture morphology in patients with advanced cuff tear arthropathy: an observational study in a surgically treated cohort.

BACKGROUND: In the presence of cuff tear arthropathy (CTA), joint kinematics is alternated and fracture configuration might be different. The purpose of this study was to identify fracture patterns in patients with advanced CTA to facilitate recognition and treatment. METHODS: Radiographs and computed tomography scans of all patients undergoing surgical treatment for a proximal humeral fracture (PHF) in our institution during a 5-year period were retrospectively analyzed. Fracture pattern according to the AO-OTA and Resch classification and the presence of CTA were evaluated. Glenoid configuration according to Walch, fatty atrophy of the supraspinatus muscle and the centrum-collum-diaphyseal (CCD) angle were analyzed. RESULTS: A total of 574 out of 713 patients were included. Twenty-three patients (4%) with a mean age of 82 ± 8 years showed advanced CTA with acetabularization of the acromion (≥ stage 3 according to Hamada/Fukuda). There were exclusively valgus fractures with a mean CCD angle of 158° ± 18°. Patients with CTA ≥ grade 3 had a nearly twofold greater risk (risk ratio: 1.8; confidence interval (CI): 95% 1.6-1.9; p < 0.0001) of sustaining a valgus fracture compared to patients without or with CTA < grade 3. The risk for a tuberosity fracture was nearly twofold greater in patients without or with mild CTA (risk ratio: 1.68; confidence interval (CI): 95% 1.17-2.40; p = 0.0046) compared to those with advanced CTA. CONCLUSION: In advanced CTA, a predominantly valgus fracture pattern can be observed. In addition, fractures of the greater tuberosity were significantly less frequent and were rarely displaced. Up to date, no classification system for PHF has been developed in the setting of CTA although it might indicate a different treatment, and therefore, recognition is crucial. However, when present, this changes the fracture pattern and ability to treat the fracture as the rotator cuff can no longer be utilized as a means of reducing the fragments.

Higher primary stability of tuberosity fixation in reverse fracture arthroplasty with 135° than with 155° humeral inclination.

BACKGROUND: Proximal humeral fractures in elderly patients are frequently treated with reverse total shoulder arthroplasty, and tuberosity healing improves clinical outcome and patient satisfaction. So far reverse prostheses with different humeral inclination (HI) angles have been used. However, it has not been investigated yet if the HI angle affects the primary stability of the tuberosity fixation in primary reverse total shoulder arthroplasty for proximal humeral fractures in a biomechanical setting. METHODS: A 4-part fracture was created in 7-paired human cadaver proximal humeri after preceding power analysis. After randomization in a pairwise fashion, reverse prostheses with either 135° (n = 7) or 155° (n = 7) were implanted. The tuberosities were reduced anatomically to the metaphysis of the prostheses and were fixed with 3 suture cerclages in a standardized technique. Tightening was performed with a cerclage tension device with 50 Newton meter (N m). Before biomechanical testing, the initial vertical and horizontal gap formation was measured. The humeri were placed in a custom-made test setup enabling internal and external rotation. Cyclic loading with a gradually increasing load magnitude was applied with a material testing machine starting with 20 N m and increasing by 5 N m after each 100th cycle until failure (>15° rotation of the tuberosities). Any motion of the tuberosities was measured with a 3-dimensional camera system. RESULTS: Overall, the 155° group reached an average of 1460 ± 270 cycles and the 135° group of 1900 ± 271 cycles (P = .048). In contrast to the 135° group, in the 155° group, a mean initial vertical (0.3 ± 0.7 mm) and horizontal (2.7 ± 3.3 mm) gap formation could be observed before cyclic loading. After 1100 cycles, the 155° group showed increased rotation of both lesser and greater tuberosities in all 3 axes around the humeral shaft compared with the 135° group. CONCLUSION: Primary stability of the reattached tuberosities is significantly increased, whereas rotational movements are decreased in prostheses with an anatomic HI of 135° compared with a 155° HI according to the original Grammont design. In addition, a 135° HI allows an exact anatomic reposition of the tuberosities, whereas this was not possible for the 155° design. However, transferability and clinical relevance of these biomechanical results have to be verified with clinical studies.

Severe Heterotopic Ossification with Proximal Entrapment of the Ulnar Nerve following Primary Anterior Shoulder Dislocation.

Heterotopic ossifications (HO) in the shoulder are rare. The effectiveness of conservative treatment is limited, and therefore, symptomatic cases are usually treated surgically. However, there are no guidelines for the surgical treatment of HO. Herein, we report the case of a 45-year-old man with severe HO and proximal entrapment of the ulnar nerve following primary anterior shoulder dislocation without concomitant injuries (e.g., fracture and rotator cuff tears). Surgical intervention was indicated, including resection of HO and neurolysis of the brachial plexus. Nine months after surgery, the patient presented with restored shoulder function, pain relief, and good patient satisfaction. The case shows that the ulnar nerve can also be impaired due to HO following shoulder dislocation.

Proximal humeral fracture morphology in patients with advanced osteoarthritis: An observational study in a surgically treated cohort.

BACKGROUND: Several factors affect proximal humeral fracture (PHF) morphology. In the presence of glenohumeral osteoarthritis (GOA), the joint kinematics is alternated which might influence fracture configuration. The purpose of this study was to identify fracture patterns in patients with advanced osteoarthritis to facilitate recognition and treatment. METHODS: In this retrospective analysis, and computed tomography (CT) scans of all patients undergoing surgical treatment for a PHF during a 5-year period were analyzed. Fracture pattern according to the AO Foundation/Orthopaedic Trauma Association (AO-OTA) classification and the presence of GOA were evaluated. In addition, critical shoulder angle (CSA), glenoid configuration, and glenoid inclination (GI) were measured. RESULTS: Of the 713 patients, 574 met the inclusion criteria. A total of 166 patients showed radiological signs of GOA (28.9%). Advanced GOA (stage 2 or 3) was identified in 23 patients (4.0%). In this group, the mean age was 77 ± 10 years, mean CSA was 28.8 ± 4.2°, and the mean GI was 19.0 ± 7.8°. All fractures were extra-articular metaphyseal fractures (5 A2, 11 A3, 7 B1.1). Patients with advanced GOA had more than threefold risk (risk ratio 3.2; confidence interval 95% 2.80-3.74; p < 0.0001) for sustaining a metaphyseal fracture. In patients with GOA grade 1 compared to patients with no radiographic signs of GOA, this could not be observed. CONCLUSION: Patients experiencing PHF with radiological signs of advanced GOA have a higher risk of sustaining a metaphyseal fracture compared to individuals with the absence of or mild GOA. To date, no classification system for PHFs takes preexisting osteoarthritis into account, although it might indicate a different treatment and therefore the recognition is crucial.

Tuberosity healing improves functional outcome following primary reverse shoulder arthroplasty for proximal humeral fractures with a 135° prosthesis.

INTRODUCTION: Reverse shoulder arthroplasty (RSA) is a common treatment for proximal humeral fractures (PHFs) in the elderly. This study evaluates the influence of tuberosity healing (TH) on functional outcome following a 135° humeral inclination RSA for PHFs. METHODS: Retrospectively, all patients with an acute PHF treated with a 135° humeral inclination RSA at four centers during a three-year period were followed up. Constant score (CS), TH and glenoid notching were analyzed. RESULTS: Sixty-four of 100 patients (64%) with a mean age of 76 ± 7 years were available for follow-up at 22 ± 8 months. The mean-adjusted CS was 72%. TH of the greater tuberosity (GT) was 77% and resulted in significantly improved forward flexion (128° vs. 92°; p = 0.003), external rotation (33° vs. 17°; p = 0.03) and adjusted CS (78% vs. 54%, p < 0.005). GT healing rate was 86% with neutral, 70% with lateralized and 33% with an inferior eccentric glenosphere. TH of the lesser tuberosity was 79%. There was 8% complication and 3% revision rate; implant survival was 100%. CONCLUSION: RSA with 135° humeral inclination for PHFs leads to good functional outcome, reproducible results and a high rate of TH. The short-term revision rate is low. TH is associated with improved ROM and functional outcome. LEVEL OF EVIDENCE: III.

High tuberosity healing rate associated with better functional outcome following primary reverse shoulder arthroplasty for proximal humeral fractures with a 135° prosthesis.

BACKGROUND: Reverse shoulder arthroplasty (RSA) is a common treatment for proximal humeral fractures. (PHF) in the elderly. This study evaluates the functional outcome and the influence of. tuberosity healing (TH) following RSA with 135° humeral inclination and a neutral glenosphere without lateralization for PHFs. METHODS: In this retrospective case series, all patients with an acute PHF treated with primary RSA with 135° humeral inclination and a standard glenosphere without lateralization during a four-year period were followed up. Constant score (CS), patient satisfaction (subjective shoulder value (SSV)), TH and glenoid notching were analyzed. RESULTS: 38 patients with a mean age of 77 ± 8 years were available for follow-up at 34 ± 5 months. The mean adjusted CS was 61 ± 9 points. TH of the greater tuberosity (GT) was 82% and resulted in significantly improved abduction (117° vs. 81°; P < 0.001), forward flexion (139° vs. 99°; p < 0.001), external rotation (28° vs. 10°; p = 0.002), CS (65 vs. 41 points; p < 0.001) and patient satisfaction (SSV 79% vs. 48%; p < 0.001). TH of the LT was 87% without affecting internal rotation or overall outcome. The complication- and revision rate was 5%; implant survival was 100%. Scapular notching occurred in 3 (8%) cases (all grade 1). CONCLUSION: RSA with 135° humeral inclination and a standard glenosphere for PHF leads to good functional outcome in combination with a high rate of TH and a low rate of scapular notching. The short-term revision rate is low and the results are predictable and continuous. TH is associated with improved ROM, patient satisfaction and functional outcome.

Latissimus dorsi transfer for massive posterosuperior rotator cuff tears: what affects the postoperative outcome?

BACKGROUND: The management of irreparable posterosuperior rotator cuff tears (IPSRCTs) in young active individuals is still a challenge. The aim of this study was to evaluate the influence of sex, surgical technique, previous surgical procedures, tear genesis, and presence of a preoperative external rotation lag sign on the functional outcome after latissimus dorsi transfer (LDT) for IPSRCTs. METHODS: Retrospectively, all patients with IPSRCTs treated with LDT during a 10-year period were followed up. Preoperative evaluation included the visual analog scale (VAS) score, range of motion, and the Constant score (CS). Postoperatively, the VAS score, range of motion, CS, American Shoulder and Elbow Surgeons score, and Subjective Shoulder Value were recorded. Preoperative and postoperative radiologic evaluation was performed using the Hamada-Fukuda classification and the acromiohumeral interval. RESULTS: In total, 67 of 79 patients (85%), with a mean age of 63 years, were available for follow-up at 54 ± 28 months. The CS improved from 24 ± 6 points preoperatively to 68 ± 17 points at follow-up (P < .001). Active flexion increased from 83° ± 47° to 144° ± 35°; abduction, from 69° ± 33° to 134° ± 42°; and external rotation, from 24° ± 18° to 35° ± 21°. Postoperatively, the Subjective Shoulder Value was 69% ± 19% and the American Shoulder and Elbow Surgeons score was 76 ± 21. The VAS score decreased from 6.3 ± 1.1 to 1.8 ± 2 (P < .001). Abduction strength increased from 0.4 ± 0.4 kg to 3.6 ± 2.2 kg (P < .001). The acromiohumeral interval decreased from 7.9 ± 2.6 mm to 5.1 ± 2.2 mm, and arthropathy worsened from Hamada-Fukuda stage 1.4 to stage 2.1. The rate of conversion to a reverse prosthesis was 6%. CONCLUSION: LDT represents a reliable and reproducible treatment option with good clinical midterm results after surgical treatment. Sex, genesis, preoperative presence of an external rotation lag sign, and previous surgical procedures do not affect the overall clinical outcome.

Osseointegrative effect of rhBMP-2 covalently bound on a titan-plasma-spray-surface after modification with chromosulfuric acid in a large animal bone gap-healing model with the Göttingen minipig.

BACKGROUND: Bone morphogenetic proteins play an important role as osseointegrative factors. It is used widely in orthopedic research and surgery to enhance the osseointegrative potential of implants, e.g., in spinal fusion or alveolar socket augmentation. The aim of the present study was to investigate the benefit of rhBMP-2 on a titan plasma spray (TPS) layer after a special modification with chromosulfuric acid (CSA) at different postoperative times, regarding osseoconduction and osseoinduction. METHODS: We allocated 27 Göttinger minipigs into three groups consisting of nine animals each. They received four dumbbell-shaped implants in the metaphyseal parts of the femora. The implants had a TPS surface with (CSA group) and without a CSA treatment (TPS group). The former received an additional layer of BMP-2 (BMP-2 group). For the assessment of osseointegration after healing periods of 4, 8, and 12 weeks, histomorphometry was applied to undecalcified specimens after staining according to Masson-Goldner. An intravital labeling with different fluorochromes was used in the gap model. A multivariable analysis with repeated measurement design was performed for statistical evaluation. RESULTS: We observed several statistical differences in a three-way ANOVA. The comparison between the BMP-2 and the TPS group (two-way ANOVA) showed statistically significant differences in terms of the osseoinduction (osteoid volume), and pronounced for the osseoconduction (bone and osteoid ongrowth), in favor of the BMP-2 group. In the pairwise comparison between BMP-2 and CSA (two-way ANOVA), no statistical significance occurred. The intravital staining with tetracycline, calcein green, and xylenol orange revealed no considerable differences between the groups. CONCLUSION: BMP-2, covalently bound on a CSA-treated TPS surface, has positive effects on the osseointegration in the large animal bone gap-healing model over the observation period of 12 weeks.

Does Acromion Morphology Depend on the Extremity or on Gender in the Population?

OBJECTIVE: The aims were to study the acromion parameters in the population and to assess the extremity or sex variation in the acromion morphology. METHODS: The lateral acromion angle (LAA) and the acromion index (AI) were assessed in a computed tomographic scan database of 250 individuals in the age group of 20 to 49 years. For the analysis of LAA and AI, 286 and 234 shoulders were available, respectively. RESULTS: The LAA was 73.6 ± 6.6 degrees; 73.7 ± 6.9 and 72.5 ± 6.1 degrees for the right and left shoulder, respectively. The AI was 0.755 ± 0.12; 0.82 ± 0.12 and 0.69 ± 0.12 for the left and the right shoulder, respectively. The AI of the right shoulder was significantly different between the 2 sexes (P = 0.04). The difference in the AI and the LAA of the right and left shoulders was significant (P < 0.0001, P = 0.04). CONCLUSIONS: The morphology of the acromion differs between the right and the left shoulders as well as between sexes.