Effects and risks of performing a single incision endoscopic plantar fasciotomy - An anatomical study.

BACKGROUND: Chronic plantar fasciitis with insufficient improvement after conservative treatment can be addressed by surgery. Endoscopic plantar fasciotomy using a single incision technique is an innovative treatment strategy. The aim of this study was to evaluate the effects and potential risks of damaging anatomical structures when performing this technique. METHODS: 40 fresh-frozen foot specimens underwent single incision endoscopic plantar fasciotomy. Operations of group A (n = 20) were done by an experienced surgeon, operations of group B (n = 20) were done by unexperienced residents. RESULTS: In both groups, all major vessels or nerves remained undamaged. Sufficient transection (>90%) was found in 16 of 20 specimens (group A) and 10 of 20 specimens (group B) (p = 0.047). CONCLUSIONS: Our results show that single incision endoscopic plantar fasciotomy can be safely performed even by unexperienced surgeons. In contrast to that, complete transection of the medial fascicle is dependent on the surgeon's experience.

Handedness-related outcome following arthroscopic shoulder stabilization.

INTRODUCTION: Bankart's repair technique represents a standard procedure for arthroscopic shoulder stabilization with excellent functional outcomes. Information concerning handedness-related outcome is missing. Here, we compare the postoperative outcome following arthroscopic shoulder stabilization in relation to handedness, taking sex and age as covariates into account. PATIENTS AND METHODS: Our retrospective dual-cohort study included 36 patients with dominant side shoulder instability (mean follow-up 33 months) and 31 patients with non-dominant side shoulder instability (mean follow-up 41 months), who underwent arthroscopic shoulder stabilization due to traumatic anterior-inferior shoulder instability. All had experienced recurrent dislocations preoperatively. The impact of handedness, and of age and sex as covariates on postoperative outcome was evaluated by the Rowe score, the apprehension test and self-reported VAS. RESULTS: Postoperatively, the Rowe score of the dominant side (mean 81.8, median 97.5) and the non-dominant side (mean 84.8, median 100) was not different (P = 0.718). Likewise, the univariate analysis for handedness (P = 0.806), sex (P = 0.627) and age (P = 0.929) as well as multivariate analysis for handedness (P = 0.721), sex (P = 0.583) and age (P = 0.898) showed no difference. The apprehension test for dominant versus non-dominant side operated patients was not different (P = 0.194). The univariate and multivariate analysis for handedness (P = 0.202 and P = 0.387, respectively) and age (P = 0.322 and P = 0.310, respectively) revealed no difference. However, the univariate and multivariate analysis for sex (P = 0.007 and P = 0.013, respectively) showed a difference. In relation to handedness, the results for the validated self-reported pain (rest pain P = 0.696, load-dependent pain P = 0.332) and surgery outcome satisfaction (P = 0.912) VAS were not different. CONCLUSIONS: Patients with shoulder instability, who underwent arthroscopic Bankart repair for stabilization of their dominant or non-dominant shoulder showed no handedness-related difference in postoperative outcome based on Rowe score, apprehension test and self-reported VAS. For the orthopedic practice, this suggests that handedness is not a risk factor for patients outcome. LEVEL OF EVIDENCE: Level IV, cohort study.

Beneficial clinical effects but limited tissue quality following osteochondral repair with a cell-free multilayered nano-composite scaffold in the talus.

BACKGROUND: The treatment of larger osteochondral lesions of the talus remains an operative challenge. In addition to micro fracturing and osteochondral transplantation one promising strategy could be the operative repair with a cell-free multilayered nano-composite scaffold with the potential to regenerate bone and cartilage in one treatment. METHODS: In this prospective case series four consecutive patients who suffered from a single osteochondral lesion (≥1.5cm2) on the medial talus were enrolled. The repair potential of the implant was assessed using MRI based biochemical, compositional MR sequences (T2 mapping) as well as semi-quantitative morphological analyses (MOCART score) at 18 months follow-up after the surgery. The clinical outcome was determined at 6-, 12-, 18-, and 24 months follow-up by using the Ankle Disability Index and the AOFAS score. RESULTS: At 18 months after the surgery, the clinical outcome was significantly improved compared to the preoperative baseline. Global T2 relaxation times of the repair tissue were significantly increased compared to the healthy control cartilage. CONCLUSIONS: Osteochondral repair with a cell-free, biomimetic scaffold provides good clinical, short-term results. However, biochemical MR imaging provides strong evidence for limited repair tissue quality at 18 months after the implantation. LEVEL OF EVIDENCE: IV.

Successful osteoconduction but limited cartilage tissue quality following osteochondral repair by a cell-free multilayered nano-composite scaffold at the knee.

INTRODUCTION: The treatment of larger osteochondral lesions in the knee is still a clinical challenge. One promising strategy to overcome this problem could be surgical repair by using a cell-free multilayered nano-composite scaffold. METHOD: In this prospective cohort study eight consecutive patients which suffered from a single osteochondral lesion (≥1.5 cm(2)) on the femoral condyle were enrolled. The repair potential of the implant was assessed by using MRI based biochemical MR sequences (T2 mapping) as well as semi-quantitative morphological analyses (MOCART score) at 18 months after the surgery. The clinical outcome was determined at six, 12, 18, and 24 month follow ups by using IKDC, Tegner-Lysholm, and Cincinnati knee scores. RESULTS: Seven out of eight patients showed a complete integration of the scaffold into the border zone and five out of eight patients excellent or good subchondral ossification of the implant at 18 months following implantation. The surface of the repair tissue was found to be intact in all eight patients. T2 mapping data and the zonal T2 index significantly differed in the repair tissue compared to the healthy control cartilage (P < 0.001) which indicates a limited quality of the repair cartilage. The clinical outcome scores consistently improved during the follow up period without reaching statistical significance. CONCLUSIONS: Osteochondral repair by implanting the MaioRegen® scaffold provides a successful osteoconduction and filling of the cartilage defect. However there is evidence for a limited repair cartilage tissue quality at 18 months after the surgery.

Reliability of radiographic landmarks in medial patello-femoral ligament reconstruction in relation to the anatomical femoral torsion.

PURPOSE: Anatomically correct graft positioning at the femoral insertion site is a key factor in surgical reconstruction of the medial patello-femoral ligament (MPFL). Basically there are two techniques to define this point in fluoroscopy during surgery. The role of the anatomical femoral torsion on the accuracy and reproducibility of both procedures has not been clarified. METHODS: Twenty human anatomical leg specimens were dissected. The femoral insertion of the MPFL was marked by two K-wires. The position of the ligament insertion was determined fluoroscopically in the true lateral view as used in routine clinical practice. The anatomical MPFL insertion was compared to the radiographic landmarks which were recommended by two previous studies. The anatomical femoral torsion of the specimens was assessed by computed tomography scans. RESULTS: In true lateral view fluoroscopy, the mean distance of the femoral MPFL insertion was -0.2 mm distal to the vertical reference line intersecting the posterior point of Blumensaat's line. In the anteroposterior direction, the mean distance was -2.0 mm posterior to the femoral cortex reference line. There was no correlation between anatomical femoral torsion and the distance of the femoral MPFL insertion to the posterior cortex. CONCLUSIONS: The results of this study strongly recommend use of a vertical line intersecting the most posterior point of Blumensaat's line as a reference to identify the MPFL insertion in the craniocaudal direction. In the anteroposterior direction, the femoral MPFL insertion showed distinctive variation and was found -2.0 mm posterior to the femoral cortex reference line without being influenced by the anatomical femoral torsion.

Prevalence of osteoarthritis and clinical results after the Elmslie-Trillat procedure: a retrospective long-term follow-up.

PURPOSE: Tibial tuberosity medialisation may be followed by osteoarthritis in the long term due to increased patellofemoral contact pressure and altered knee joint kinematics. We aimed to (1) systematically assess the grades of tibiofemoral and patellofemoral osteoarthritis ten to 30 years after the Elmslie-Trillat procedure and (2) to evaluate long-term knee function and activities of daily living. METHODS: A total of 26 patients (30 knees) were re-evaluated at a minimum follow-up of 12.3 years (mean 20.9 ± 4.1 years). Osteoarthritis was graded according to Kellgren and Lawrence (K/L) and Sperner. All patients were clinically evaluated using the Knee Society Score (KSS) and Knee injury and Osteoarthritis Outcome Score (KOOS). Radiographic data were compared to an age-, sex- and body mass index-matched control group of healthy patients. RESULTS: Radiographic evaluation revealed seven cases (23.3%) with advanced osteoarthritis (K/L and Sperner grades 3 and 4). However, the observed differences from the matched cohort were not statistically significant (P = 0.189). A positive correlation was found between the age at index procedure and tibiofemoral osteoarthritis at follow-up (P = 0.013). Patient satisfaction was relatively high, showing a mean KSS of 89.9 (knee score) and 94.8 (function score), and a mean KOOS of 78.7. However, we noted four cases of frequent patellar re-dislocations and three total knee arthroplasties. CONCLUSIONS: The Elmslie-Trillat procedure was associated with several cases of advanced tibiofemoral and patellofemoral osteoarthritis in the long term, especially if the procedure was performed late. Clinical results were still good to excellent in the majority of patients despite some observed cases of re-dislocations and decreased ability to perform sports.

Evaluation of fibrin-based gene-activated matrices for BMP2/7 plasmid codelivery in a rat nonunion model.

PURPOSE: Treatment of large-segmental bone defects still is a challenge in clinical routine. Application of gene-activated matrices (GAMs) based on fibrin, bone morphogenic protein (BMP) 2/7 plasmids and nonviral transfection reagents (cationic polymers) could be an innovative treatment strategy to overcome this problem. The aim of this study was to determine the therapeutic efficacy of fibrin GAMs with or without additional transfection reagents for BMP2 and 7 plasmid codelivery in a femur nonunion rat model. METHODS: In this experimental study, a critical-sized femoral defect was created in 27 rats. At four weeks after the surgery, animals were separated into four groups and underwent a second operation. Fibrin clots containing BMP2/7 plasmids with and without cationic polymer were implanted into the femoral defect. Fibrin clots containing recombinant human (rh) BMP2 served as positive and clots without supplement as negative controls. RESULTS: At eight weeks, animals that received GAMs containing the cationic polymer and BMP2/7 plasmids showed decreased bone volume compared with animals treated with GAMs and BMP2/7 only. Application of BMP2/7 plasmids in fibrin GAMs without cationic polymer led to variable results. Animals that received rhBMP2 protein showed increased bone volume, and osseous unions were achieved in two of six animals. CONCLUSIONS: Cationic polymers decrease therapeutic efficiency of fibrin GAM-based BMP2/7 plasmid codelivery in bone regeneration. Nonviral gene transfer of BMP2/7 plasmids needs alternative promoters (e.g. by sonoporation, electroporation) to produce beneficial clinical effects.

Femoral rotation in ligament balanced knee arthroplasty: a prospective clinical study.

Rotational alignment of the femoral component is an important factor to achieve beneficial results in total knee arthroplasty. Femoral rotation pre versus post surgery was prospectively assessed in 40 patients who underwent ligament balanced knee arthroplasty. Computerized tomography of the knee was performed before and after the surgery to determine the femoral rotation. In 36 out of 40 patients the rotation of the femoral implants differed compared to the preoperative femur (P > 0.001). After surgery the rotational alignment of the femoral component ranged from -3° (internal rotation) to 7° (external rotation). Increased external rotation was found in 33 out of 40 patients ranging from 1° to 7°. These results highlight the importance of individually determined femoral rotation in ligament balanced knee arthroplasty.

Metatarsal length does not correlate with maximal peak pressure and maximal force.

BACKGROUND: Primary metatarsalgia of the lesser metatarsals is common and caused by mechanical overload of the affected metatarsal heads. Increased metatarsal length generally is believed to be a factor in the development of primary metatarsalgia. However, there is no clear biomechanical evidence supporting this theory. QUESTIONS/PURPOSES: We asked whether metatarsal length correlated with plantar-loading parameters under the corresponding metatarsal heads. PATIENTS AND METHODS: We prospectively followed two groups of patients 46 (51 feet) with and 45 (51 feet) without metatarsalgia. Each foot was physically examined and underwent standardized full-weightbearing radiography and dynamic pedobarography to assess maximal peak pressure and maximal force under the first, second, and third metatarsal heads. We correlated the relative length of the first and third metatarsals with the corresponding two plantar-loading parameters. We compared maximal peak pressure and maximal force in patients with metatarsalgia with those of symptom-free patients. RESULTS: The relative length of the first and third metatarsals did not correlate (r < 0.13) with the maximal peak pressure or maximal force under the corresponding metatarsal heads. Maximal force under the first metatarsal head was decreased in the metatarsalgia group. There was no difference in maximal peak pressure between the metatarsalgia and nonmetatarsalgia groups. CONCLUSIONS: Relative metatarsal length had no influence on plantar-loading parameters. Shortening of a symptomatic ray to decrease plantar-loading parameters cannot be supported from a biomechanical rationale.

Double-plate fixation in lateral clavicle fractures-a new strategy.

BACKGROUND: Lateral clavicle fractures Neer type II often lead to the dislocation of the medial fragment and an increased rate of nonunion after conservative treatment. Therefore, most authors recommend an open reduction and internal fixation. Double-plate fixation is a common technique in the treatment of complex radius fractures. The authors use it as a routine procedure in the treatment of lateral clavicle fractures Neer type II. In this article, we present our experiences. METHODS: From January 2006 to June 2008, 11 patients with lateral clavicle fractures of Neer type II were treated with an open reduction and internal fixation using the double-plate technique. RESULTS: All patients showed osseous union on radiographs after 10 weeks to 16 weeks. In eight of nine cases, the operated shoulder regained full range of motion. In all patients, we observed immediate postoperative recovery without severe complications. One female patient complained about slight pain and restricted motion in abduction of > 90°. In two patients, we observed the migration of one screw. It was removed under local anesthesia 9 weeks and 26 weeks after surgery. CONCLUSIONS: This study, for the first time, describes the technique of double-plate fixation for the treatment of lateral clavicle fractures. This technique provides a stable fixation even in small and comminuted distal fragments.

Convincing long-term results independent from the postoperative leg alignment following cementless total knee arthroplasty.

BACKGROUND: Cementless primary total knee arthroplasty shows numerous advantages compared with cemented implants (e.g., shorter operation time, preservation of the bone stock). Up to now an increasing number of clinical long-term studies exist. Despite this fact, there is no evidence about the influence of the postoperative leg alignment on the results of cementless knee arthroplasty. There is no work on the clinical outcome of the specific implant, which was used in this study (VANGUARD®, ZimmerBiomet). The purpose of this study was to assess the clinical and radiological long-term results after cementless knee arthroplasty in relation to the postoperative mechanical leg alignment. METHODS: Clinical and radiological results were retrospectively assessed in 83 patients at 10.3 years (ranging from 9.6 to 11.8 years) after implantation. Hip-knee-ankle angle (HKA) was measured, and the patients were separated into a corrected (HKA between three degrees of varus and three degrees of valgus, n = 60) and a varus/valgus (HKA > 3° of varus and valgus, n = 23) group. RESULTS: Up to the time of the clinical follow-up, three out of 83 patients already underwent a revision surgery due to a deep infection (3.6%). Tegner-Lysholm Knee scale was 89.1 in the corrected group and 88.8 in the varus/valgus group (p = .94). The mean Knee Injury and Osteoarthritis Outcome score (KOOS) was 81.2 in the corrected group and 82.4 in the varus/valgus group (p = .63). CONCLUSIONS: Results of this study showed convincing clinical and radiological results after primary cementless knee arthroplasty. Under- or overcorrected postoperative mechanical leg alignments did not influence the long-term clinical results.

Risk of Damaging Anatomical Structures During Minimally Invasive Hallux Valgus Correction (Bösch Technique): An Anatomical Study.

BACKGROUND: Percutaneous, transverse distal metatarsal osteotomy with K-wire fixation (the Bösch technique) is an established technique for hallux valgus correction. Nevertheless, the risk of damaging the anatomical structures during the operation is unknown. METHODS: Forty fresh-frozen anatomical foot specimens with hallux valgus deformity underwent a percutaneous corrective procedure. Specimens of group A (n = 20) were operated by an experienced surgeon while specimens of group B (n = 20) were done by untrained residents. RESULTS: The dorsal cutaneous nerve was injured in 1 of 20 cases in group A and 6 of 20 cases in group B ( P = .037). There was a significant difference in overall complication rate between specimens of group A and group B ( P = .043). CONCLUSIONS: The results show an increased risk of perioperative injury of the dorsal cutaneous branch of the deep peroneal nerve as well as a significant effect of the surgeon's experience on the overall complication rate. CLINICAL RELEVANCE: Results of this study are highly relevant for all surgeons who perform percutaneous, minimally invasive hallux valgus surgery to avoid damage to the peripheral nerves. In addition, the data suggest an intensive training for surgeons before minimally invasive hallux valgus surgery is performed without supervision.

Migration characteristics and early clinical results of the NANOS® short-stem hip arthroplasty.

BACKGROUND: Femoral short stems promise essential advantages in total hip arthroplasty. Up to now, only short- and midterm clinical studies exist. Data on early stem migration that could predict later aseptic loosening at an early stage are rare. The purpose of this study was to assess migration patterns and clinical outcome 2 years after hip replacement by a metaphyseal anchored cementless short stem. METHODS: Migration data and clinical results were prospectively assessed in 49 patients. Clinical outcome was measured using the Harris Hip Score (HHS). Migration analyses were performed using the computer-assisted Einzel-Bild-Roentgen-Analyse (EBRA) system. RESULTS: At 2 years after surgery, none of the implants needed revision, and HHS increased from 47.9 up to 98.1. Of 49 patients, 5 (10%) showed increased vertical stem migration (1.5 mm/2a) that might predict late aseptic loosening. Of 49 stems, 44 (90%) showed stable migration patterns indicating a beneficial long-term outcome. CONCLUSIONS: Results of this study confirm the excellent clinical data of previous works. Migration patterns strongly suggest that short-stem arthroplasty is not only an innovative but also a reliable strategy in total hip replacement.

Migration characteristics and early clinical results of a novel-finned press-fit acetabular cup.

BACKGROUND: Ana Nova® is a novel-finned press-fit acetabular cup which showed superior biomechanical characteristics in an experimental set-up. Using Einzel Bild Röntgen Analyse (EBRA) measurements should offer the opportunity to predict implant survival at an early stage. The purpose of this study was to assess migration and clinical outcome 2 years after total hip replacement by a novel-finned press-fit acetabular cup. METHODS: In this study, migration and clinical results of the implant were prospectively assessed in 67 patients. Clinical outcome was assessed using the Harris hip score (HHS). Migration analyses were performed using the computer assisted EBRA system. Data were analyzed for normal distribution using the Kolmogorov-Smirnov test. Group comparisons were performed using the analysis of variance (ANOVA) test. P-values less than 0.05 were considered statistically significant. RESULTS: At 2 years after surgery, none of the implants needed revision and HHS increased from 39.7 up to 92.2. In contrast to the beneficial clinical outcome, 17 of 44 patients showed increased total migration ( 1 mm/2a). CONCLUSIONS: Adverse migration data in this study might predict aseptic loosening and decreased survival of the implant. According to previous studies, it is possible that this effect occurred because of limited accuracy of the EBRA system. In our opinion, migration analyses may not be recommended as a screening tool in a 2 year follow-up.

Functional and radiographic consideration of lower limb malalignment in children and adolescents with idiopathic genu valgum.

Three-dimensional gait analysis is capable of assessing dynamic load characteristics and the resulting compensatory effects of lower limb malalignment, which are generally not reflected in static imaging. This study determined differences in gait parameters in the frontal and transverse plane between patients and controls in order to identify compensatory mechanisms, and to correlate radiographic measurements and gait parameters in a consecutive series of children with idiopathic genu valgum. Thirty-three patients (mean age 12.3 years) were retrospectively reviewed and compared to a healthy control group. Children with genu valgum demonstrated significantly decreased internal knee valgus moments, shifting into varus moments. Furthermore, significantly different transverse plane gait patterns (decreased external knee rotation, increased external hip rotation) were observed. These patterns showed a relevant influence on the frontal knee moments, with knee rotation and foot progression angle showing the highest predictive value for changes and possible compensation of frontal knee moments. The correlation between commonly used radiographic measurements (i.e., mechanical axis deviation) and findings of the gait analysis was only low. Besides showing decreased internal knee valgus moments, our results suggest that considerable compensatory gait mechanisms may be present in children with idiopathic genu valgum to reduce joint loading.

Sonoporation increases therapeutic efficacy of inducible and constitutive BMP2/7 in vivo gene delivery.

An ideal novel treatment for bone defects should provide regeneration without autologous or allogenous grafting, exogenous cells, growth factors, or biomaterials while ensuring spatial and temporal control as well as safety. Therefore, a novel osteoinductive nonviral in vivo gene therapy approach using sonoporation was investigated in ectopic and orthotopic models. Constitutive or regulated, doxycycline-inducible, bone morphogenetic protein 2 and 7 coexpression plasmids were repeatedly applied for 5 days. Ectopic and orthotopic gene transfer efficacy was monitored by coapplication of a luciferase plasmid and bioluminescence imaging. Orthotopic plasmid DNA distribution was investigated using a novel plasmid-labeling method. Luciferase imaging demonstrated an increased trend (61% vs. 100%) of gene transfer efficacy, and micro-computed tomography evaluation showed significantly enhanced frequency of ectopic bone formation for sonoporation compared with passive gene delivery (46% vs. 100%) dependent on applied ultrasound power. Bone formation by the inducible system (83%) was stringently controlled by doxycycline in vivo, and no ectopic bone formation was observed without induction or with passive gene transfer without sonoporation. Orthotopic evaluation in a rat femur segmental defect model demonstrated an increased trend of gene transfer efficacy using sonoporation. Investigation of DNA distribution demonstrated extensive binding of plasmid DNA to bone tissue. Sonoporated animals displayed a potentially increased union rate (33%) without extensive callus formation or heterotopic ossification. We conclude that sonoporation of BMP2/7 coexpression plasmids is a feasible, minimally invasive method for osteoinduction and that improvement of bone regeneration by sonoporative gene delivery is superior to passive gene delivery.

Structural and biomechanical characteristics after early mobilization in an Achilles tendon rupture model: operative versus nonoperative treatment.

Acute Achilles tendon ruptures are common sports injuries; however, treatment remains a clinical challenge. Studies show a superior effect of early mobilization and full weight bearing on tendon healing and clinical outcome; however, few data exist on structural and biomechanical characteristics in the early healing phase. This study investigated the histological and biomechanical characteristics of early mobilization and full weight bearing in an Achilles tendon rupture model. Eighty rats underwent dissection of a hindpaw Achilles tendon; 40 rats were treated conservatively and 40 underwent open repair of the transected Achilles tendon by suturing. Early mobilization and full weight bearing were allowed in both groups. At 1, 2, 4, and 8 weeks after tenotomy, tensile strength, stiffness, thickness, tissue characteristics (histological analysis), and length were determined. Dissected Achilles tendons healed in all animals during full weight-bearing early mobilization. One and 2 weeks after tenotomy, rats in the operative group showed increased tensile strength and stiffness compared with the nonoperative group. Repair-site diameters were increased at 1, 2, and 8 weeks after tenotomy. Tendon length was decreased in the operative group throughout observation, whereas the nonoperative group showed increased structural characteristics on the cellular level and a more homogeneous collagen distribution. Surgical treatment of dissected rat Achilles tendons showed superior biomechanical characteristics within the first 2 weeks. Conservative treatment resulted in superior histological findings but significant lengthening of the tendon in the early healing phase (weeks 1-8).

BMP-2 but not VEGF or PDGF in fibrin matrix supports bone healing in a delayed-union rat model.

Treatment of delayed bone healing and non-unions after fractures, osteotomies or arthrodesis still is a relevant clinical challenge. Artificially applied growth factors can increase bone healing and progressively gain importance in clinical routine. The aim of this study was to determine the effects of rhPDGF-BB, rhVEGF-165, and rhBMP-2 in fibrin matrix on bone healing in a delayed-union rat model. Thirty-seven rats underwent a first operation where a standardized femoral critical size defect was created. A silicone spacer was implanted to impair vascularization within the defect. At 4 weeks the spacer was removed in a second operation and rhPDGF-BB, rhVEGF-165, or rhBMP-2 were applied in a fibrin clot. Animals in a fourth group received a fibrin clot without growth factors. At 8 weeks fibrin bound rhBMP-2 treated animals showed a significantly increased union rate and bone volume within the defect compared to the other groups. Single application of fibrin bound rhPDGF-BB and rhVEGF-165 failed to increase bone healing in our atrophic non-union model.

Sex-related outcome differences after arthroscopic shoulder stabilization.

Arthroscopic shoulder stabilization using Bankart's repair technique has become a standard intervention in the treatment of traumatic shoulder instability. Nevertheless, knowledge about sex-related differences postoperatively is scarce. The goal of our study was to compare the outcome of men and women after arthroscopic shoulder stabilization. All patients underwent arthroscopic shoulder stabilization due to anterior shoulder instability after traumatic shoulder dislocation. Patients received a standardized questionnaire for evaluating subjective parameters. Subsequently, patients were clinically examined by orthopedic physicians where their Constant-Murley score was raised, and apprehension and sulcus sign tests were conducted. The study included 24 men (mean age, 29.9 years; mean follow-up, 55 months) and 12 women (mean age, 31.8 years; mean follow-up, 62.3 months). Women showed a significantly decreased Constant-Murley score compared to men (P=.045). A positive apprehension test indicating decreased shoulder stability was found more often in women (P=.018). A positive sulcus sign test indicating increased joint laxity was found in 25% of women and only 12.5% of men without reaching statistical significance (P=.378). Compared to men, shoulder function as well as shoulder stability was significantly decreased in women after arthroscopic shoulder stabilization.

Vagus nerve stimulation regulates hemostasis in swine.

The central nervous system regulates peripheral immune responses via the vagus nerve, the primary neural component of the cholinergic anti-inflammatory pathway. Electrical stimulation of the vagus nerve suppresses proinflammatory cytokine release in response to endotoxin, I/R injury, and hypovolemic shock and protects against lethal hypotension. To determine the effect of vagus nerve stimulation on coagulation pathways, anesthetized pigs were subjected to partial ear resection before and after electrical vagus nerve stimulation. We observed that electrical vagus nerve stimulation significantly decreased bleeding time (pre-electrical vagus nerve stimulation = 1033 +/- 210 s versus post-electrical vagus nerve stimulation = 585 +/- 111 s; P < 0.05) and total blood loss (pre-electrical vagus nerve stimulation = 48.4 +/- 6.8 mL versus post-electrical vagus nerve stimulation = 26.3 +/- 6.7 mL; P < 0.05). Reduced bleeding time after vagus nerve stimulation was independent of changes in heart rate or blood pressure and correlated with increased thrombin/antithrombin III complex generation in shed blood. These data indicate that electrical stimulation of the vagus nerve attenuates peripheral hemorrhage in a porcine model of soft tissue injury and that this protective effect is associated with increased coagulation factor activity.