We report in the following on our technique of endoscopic sacroiliacal screw removal as a new extra-articular endoscopic method in soft tissue surgery, aimed at the reduction of radiation exposure for both the patient and the surgical teams.

The purpose of this study was to evaluate the effects of partial and full weightbearing after cementless total hip arthroplasty over a two year follow-up period. Fifty-nine women and 41 men (average age 61 years) received an uncemented Spotorno stem and were randomised into a full and a partial weightbearing group. No significant difference was found between the groups with regard to the Merle d' Aubigne hip score, VAS pain level, shaft migration or radiographic signs of bony ingrowth. All femoral components seemed radiologically well-fixed and showed bone ingrowth at 24 months. Provided that solid initial fixation is obtained full weightbearing immediately after cementless total hip arthroplasty using a hydroxyapatite-coated Spotorno-type femoral shaft component can be recommended.

Purpose The aim of this study was to compare the functional outcome, quality of restoration, and complication rate after open reduction and internal fixation (ORIF) of displaced or unstable 2-, 3- and 4-part humeral fractures using two different locking plates. Methods The data used in this analysis was prospectively collected in two large multicentre studies in 15 European Level 1 trauma centres. A total of 318 patients with proximal humeral fractures were treated with ORIF using either the locking proximal humerus plate (LPHP) or proximal humeral internal locking system (PHILOS). Outcome measurements included Constant and Neer scores, evaluation of local pain at the fracture site and complications, and radiographic assessment at one year. Results At one year, the mean Constant scores (relative to the contralateral shoulder) improved significantly for both groups and were above 80% for 2-, 3-, and 4-part fractures. A significantly shorter surgical time, less pain at the fracture site, and better functional outcome was achieved by PHILOS-treated patients with 2-part fractures throughout the one-year follow-up month and with 3-part fractures at three months ( p < 0.05). There was no difference between the treatment outcomes for 4-part fractures, and no difference in the complication rates ( p > 0.05). Conclusions PHILOS and LPHP can be considered as useful implants for ORIF of displaced and unstable proximal humeral fractures. There was a slight advantage of the PHILOS system with regard to operative time and functional outcome, especially for the treatment of 2- and 3-part fractures.

Background: Path analysis methods were used to test the prognostic value of 10 patient-related and treatment-related factors on the 1-year functional outcome of 463 proximal humeral fractures measured using the Constant score. Complex inter-relationships between these factors were also evaluated.Materials and methods: Data were collected from a prospective cohort study that included 3 operative groups repaired using nail or plate fixation and 1 nonoperative group. From the available information, various factors potentially having a direct influence on the functional Constant score were identified. The process of creating a hypothetical causal path diagram was undertaken to order the factors in a sequence of associations or cause-and-effect relationships.Results: Our final multivariable regression model for the 1-year Constant score included the 6 factors of age, sex, treatment, occurrence of intraoperative and local post-treatment complications, and anatomic restoration. Being a woman aged older than 40 years, treated with a locking proximal humeral plate (LPHP), having experienced intraoperative and local post-treatment complications, and varus deformity of more than 30 degrees were negative predictors of the Constant score (ie, poor shoulder function 1 year after treatment initiation). Three factors, the dominant side fractured and the Neer and AO fracture type, showed only significant association on intermediate factors. The presence of concomitant disease did not show any significant direct or indirect effect. A final pathway outlines these associations and inter-relationships.Conclusion: Prevention of local complications, in particular those leading to severe varus deviation, appears essential to improve shoulder function after a proximal humeral fracture.Level of evidence: Level I, Prospective Design, Prognosis Study. (C) 2011 Journal of Shoulder and Elbow Surgery Board of Trustees.

BACKGROUND:There is a lack of consensus regarding optimal surgical management of displaced and unstable three-part proximal humeral fractures.QUESTIONS/PURPOSES:The objective of this prospective observational study was to compare the clinical and radiologic outcomes of plate versus nail fixation of three-part proximal humeral fractures.PATIENTS AND METHODS:Two hundred eleven patients with unstable three-part proximal humeral fractures were treated with ORIF using plate (PHILOS [proximal humeral interlocking system]/LPHP [locking proximal humerus plate]) or nail (PHN [proximal humeral nail]) osteosynthesis. Outcome measurements included pain, Constant and Murley and Neer scores, and the occurrence of complications at 3, 6, and 12 months postsurgery. Regression analysis and the likelihood ratio test were used to evaluate differences between the cohorts.RESULTS:Throughout the 1-year followup period the Constant and Murley scores improved significantly for both cohorts; there was no significant difference between the nail group compared with the plate group. Also, 1-year Neer scores were similar between the two cohorts. Patients in the PHN group perceived significantly less pain compared with patients in the plate fixation group at 3, 6 and 12 months after surgery. We observed 79 local complications in 60 patients with no significant risk difference between the treatment groups; 35 intraoperative complications were directly related to the initial surgical procedure.CONCLUSIONS:The similar 1-year outcomes for nail versus plate fixation of three-part proximal humeral fractures suggest that both techniques may be useful for internal fixation of these fractures. Many complications were related to incorrect surgical technique and therefore can be avoided. Advanced surgical skills and experience are considered to be more critical for successful operative treatment of three-part proximal humeral fractures than the selection of the implant.LEVEL OF EVIDENCE:Level II, therapeutic study (prospective comparative study). See the Guidelines for Authors for a complete description of levels of evidence.

背景：肱骨近端不稳定性移位骨折的治疗仍有争议，尤其是老年患者。本前瞻性多中心病例研究目的是评价肱骨近端骨折采用切开复位肱骨近端锁定钢板内固定后的功能和并发症的发生率。方法：187例肱骨近端新鲜骨折患者（平均年龄62．9-15．7岁）行切开复位肱骨近端锁定钢板内固定。分别在术后3个月、6个月和1年进行随访，获得随访的患者人数分别为165例（88％）、158例（84％）和155例（83％），并对疼痛、肩部活动度和肌力进行评价。每次随访时均作Constant肩关节评分，术后1年随访时作患肢和对侧肢体的上肢、肩、手残疾评分（DASH）。结果：3个月和1年的随访结果比较发现，患侧的平均活动范围和Constant评分都显著改善。术后1年，患侧平均Constant评分为70．6±13．7分，而对侧肢体为85．1％-14．0％。1年后随访时平均DASH评分为15．2±16．8。1年后对155例患者随访时发现其中有52例（占34％）患者共计发生并发症62例次。其中25例并发症（占40％）与手术技巧不当有关，而且都发生在手术过程的最后。最常见的并发症是术中螺钉穿出肱骨头，155例患者中的21例（14％）发生螺钉穿出。29例患者在骨折后12个月内进行了计划外的第二次手术。结论：本研究认为如果采用正确的手术技巧对于移位的肱骨近端骨折采取手术治疗并用肱骨近端锁定钢板固定可以取得良好的功能。由于大部分并发症和不正确的手术技巧有关，因此手术医生应该掌握正确的手术技巧以避免医原性损伤。可信水平：治疗性研究Ⅳ级。关于证据等级的完整描述详见投稿须知。

Durch den Einsatz navigierter Verfahren kann bei der perkutanen transiliosakralen Verschraubung eine höhere Präzision erreicht werden. Zielsetzung dieser Studie war es, den Einfluss der Navigationserfahrung des Operateurs auf die Schraubenlage 3D-navigiert implantierter SI-Schrauben zu evaluieren.

The purpose of this study was to evaluate the effects of partial and full weightbearing after cementless total hip arthroplasty over a two year follow-up period. Fifty-nine women and 41 men (average age 61 years) received an uncemented Spotorno stem and were randomised into a full and a partial weightbearing group. No significant difference was found between the groups with regard to the Merle d' Aubigne hip score, VAS pain level, shaft migration or radiographic signs of bony ingrowth. All femoral components seemed radiologically well-fixed and showed bone ingrowth at 24 months. Provided that solid initial fixation is obtained full weightbearing immediately after cementless total hip arthroplasty using a hydroxyapatite-coated Spotorno-type femoral shaft component can be recommended.

The precision of sacroiliac screw placement can be improved with the use of navigation techniques. The purpose of this study was to evaluate the accuracy of 3D-navigated sacroiliac screw positioning in relation to the surgeon's experience with the navigation technique.A consecutive series of 3D-navigated sacroiliac screw placements were prospectively evaluated between December 2005 and February 2008. Postoperatively the precision of screw placement was analyzed in relation to the surgeon's navigation experience with a CT-scan using the criteria of Smith.A total of 37 screws were implanted by 7 surgeons in 33 patients. In the group of surgeons with less experience in navigation techniques two cases of malpositioning led to revision of the screws. No screws which were implanted or assisted by surgeons experienced in navigation needed to be revised. There was no significant difference in the malposition rate.In the clinical setup a malpositioning of sacroiliac screws is possible even with the use of 3D navigation. One reason may be a low level of navigation experience of the surgeon in combination with low experience in the conventional technique. Therefore even in navigation-based placement of sacroiliac screws the malpositioning rate is dependent on the surgeon's experience with the navigation technique. The correct placement of the screws should be controlled intraoperatively using the 3D image intensifier.

BACKGROUNDConventional percutaneous iliosacral screw placement in pelvic surgery is considered to be a highly demanding operative technique with a high rate of screw malpositions, which may be associated with the risk of neurologic damage or inefficient stability. In the conventional technique, the correct entry point for the screw and the small target corridor for the iliosacral screw may be difficult to visualize using an image intensifier. We tried to find out in this study whether the positioning of percutaneous screw implantations could be optimized by evaluating the rate and grade of malpositions and whether the needed revisions could be reduced by using computer navigation and three-dimensional (3D) image intensifier.METHODSA group of 54 patients with 63 screws implanted using computer navigation was compared with 87 patients with 131 screws implanted using the conventional fluoroscopic technique. The exact screw position was controlled in a postoperative computed tomography scan, and the grade of malposition of every screw was investigated and compared.RESULTSA complete intraosseous screw position was found in 42% of cases using the conventional technique and was significantly less compared with 81% using a 3D image intensifier in combination with a navigation system. Moreover, the revision rate of 1.6% was significantly less in the navigated group compared with 19% in the conventional group.CONCLUSIONSThe results indicate that 3D-computer navigation of the percutaneous iliosacral screw insertion can facilitate surgical performance in respect to reducing screw malposition and revision rates.

We present a study designed to investigate whether the intramedullary bone endoscopy (IBE) procedure within the cavity of an intact long bone will create embolic loads on the lungs similar to that of other orthopedic procedures (e.g., stem implantation in total hip arthroplasty [THA]). In a sheep model, 10 animals underwent the IBE procedure with complete perioperative anesthesiology monitoring. The lungs were harvested postoperatively and examined for fat embolisms. One animal showed evidence of intraoperative fat embolism with temporary increases in mean pulmonary arterial pressure (MPAD) and the mean CO 2 ‐gradient. The histological examination in this animal revealed fat embolism with a 2% surface area of the investigated fields covered with fat vacuoles. All peri‐ and postoperative data on the other nine animals were normal. Our findings indicate that, as with other intramedullary manipulation in intact long bones, there is a potential risk for systemic fat excavation during IBE. However, the embolic load is much lower than the rates reported for other orthopedic interventions. © 2009 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 27: 1060–1066, 2009

Studienziel: Methode: Ergebnisse: Schlussfolgerungen: Aim: Method: Results: Conclusions:

Insertion of percutaneous iliosacral screws with fluoroscopic guidance is associated with a relatively high screw malposition rate and long radiation exposure. We asked whether radiation exposure was reduced and screw position improved in patients having percutaneous iliosacral screw insertion using computer-assisted navigation compared with patients having conventional fluoroscopic screw placement. We inserted 26 screws in 24 patients using the navigation system and 35 screws in 32 patients using the conventional fluoroscopic technique. Two subgroups were analyzed, one in which only one iliosacral screw was placed and another with additional use of an external fixator. We determined screw positions by computed tomography and compared operation time, radiation exposure, and screw position. We observed no difference in operative times. Radiation exposure was reduced for the patients and operating room personnel with computer assistance. The postoperative computed tomography scan showed better screw position and fewer malpositioned screws in the three-dimensional navigated groups. Computer navigation reduced malposition rate and radiation exposure.Level of Evidence: Level II, therapeutic study. See the Guidelines for Authors for a complete description of levels of evidence.

Study Design. Comparison of the dose area product (DAP), the radiation time and the operation time during computer navigated and conventional balloon kyphoplasty procedures. Objective. To compare the patients radiation exposure and operation time in a balloon kyphoplasty procedure with and without using a navigation system for the placement of working needles. Summary of Background Data. Minimal invasive spine surgery is associated with high radiation exposure for both the patient and the surgeon. The use of computer navigation has led to a reduced radiation exposure in experimental trials. To our knowledge, there is no clinical data determining the influence of computer navigation on radiation exposure and operation time in a balloon kyphoplasty procedure. Methods. Twenty-nine patients with 30 osteoporotic vertebra fractures were treated with a computer-navigated kyphoplasty. The placement of the working needles in thoracic spine fractures was performed after acquiring an intraoperative three-dimensional data set. Fractures of the lumbar spine were treated using fluoroscopic three-dimensional navigation. During each procedure the operation time, the overall radiation time, and the DAP were documented. The data of the navigated operations were compared to a control group of consisting of 30 conventional balloon kyphoplasty procedures. Results. In the conventional kyphoplasty group the average operation times for thoracic spine (ts) and lumbar spine (ls) were 61 and 57 minutes, respectively. The average radiation times were 175 and 165 seconds. The DAP applied to the patient was 1972 and 2105 cGy cm2. The average operation times in the navigated group were 67 minutes in the ts and 62 minutes in the ls. The average radiation time was reduced significantly in the navigated group (99 seconds ts and 74 seconds ls). The DAP applied to the patient was also significantly lower (1245 cGy cm2 (ts) and 1318 cGy cm2 (ls)). Conclusion. The use of computer navigation systems in balloon kyphoplasty procedures reduces the radiation exposure of patients and surgeons significantly. The increased technical effort did not lead to a significant longer operation time. Hence, the use of computer navigation systems in balloon kyphoplasty procedures is recommended.

Between 1999 and 2002, 16 patients with osteochondral lesions on the central and posterior talar dome underwent osteochondral autografting. A new approach with temporary removal and replacement of a tibial bone block from the anterior tibial plafond was adopted. Inclusion criteria were joint stability, an age between 18 and 50 years, and osteochondral lesions stages 3 and 4 according to the radiological classification of Loomer, for which previous arthroscopic treatment was not successful. All patients underwent clinical and MRI evaluation after 12, 35 and 59 months. The AOFAS Ankle Hindfoot score improved significantly between the preoperative period and 1 year (p < 0.001), between 1 and 3 years (p < 0.001), but not between 3 and 5 years postoperative (p = 0.37). The score was independent from patients gender (p = 0.44) and age. The Spearman coefficient of correlation between clinical outcome and defect size was - 0.79 (p = 0.01), indicating that patients with small lesions had the best results. Control radiographs and MRIs showed no reduced joint space and good integration of the tibial bone block without incongruency. Osteochondral grafting with temporary removal of a tibial bone block is a successful technique with good midterm results in osteochondral talar lesions for which arthroscopic excision, curettage and drilling has failed.

BACKGROUND Navigated implantation of total knee prostheses has become more and more popular within the last decade in orthopaedic surgery. Although improved alignment after navigated knee surgery has been reported previously in the literature, only a few studies meet the criteria of a level-1 evidence-based medicine study. We present the results of a controlled and prospective study comparing early clinical outcomes after computer-assisted versus conventional implantation in total knee arthroplasty (TKA). METHODS Within a 15-month period, all patients admitted for primary TKA were followed prospectively. Each patient was evaluated using the Knee Society Score (KSS) preoperatively, 10 days after surgery, and 3 months after surgery. The patients were divided into two groups, and the implantation technique altered between the two treatment options: each conventional implantation was strictly followed by a computer-assisted procedure and vice versa. RESULTS From March 2003 to June 2004, we did 34 computer-assisted (group A) and 35 conventional knee arthroplasties (group B) in 62 patients. There was no difference in the preoperative status of the patients. Surgeries in group A took significantly longer than in group B. The average deviation from correct alignment was significantly reduced in group A. 66 of 69 of the TKAs were available for follow-up examinations after 10 days and after 3 months. No significant differences were found in the overall KSS scores or in the subgroups. CONCLUSIONS The intraoperative use of a computer-assisted navigation system during implantation of a total knee prosthesis reduced the average varus/valgus deviation from the anatomical long leg axis. A disadvantage of the computer-assisted surgical procedure may be the longer operating time. Long-term follow-up of the presented data is needed in order to show whether the improved average alignment is advantageous for patients and/or results in a longer service life of the TKA.

Zur Evaluierung des Nutzens von Navigationsgeräten in der Knieendoprothetik existieren bislang nur wenige evidenzbasierte Studien. Die vorliegende Analyse einer kontrollierten und prospektiven Studie zeigt die Frühergebnisse von konventioneller vs. navigationsgestützter Implantationstechnik.

The objective of this retrospective study was to correlate the Bado and Jupiter classifications with long-term results after operative treatment of Monteggia fractures in adults and to determine prognostic factors for functional outcome. Of 63 adult patients who sustained a Monteggia fracture in a ten-year period, 47 were available for follow-up after a mean time of 8.4 years (5 to 14). According to the Broberg and Morrey elbow scale, 22 patients (47%) had excellent, 12 (26%) good, nine (19%) fair and four (8%) poor results at the last follow-up. A total of 12 patients (26%) needed a second operation within 12 months of the initial operation. The mean Broberg and Morrey score was 87.2 (45 to 100) and the mean DASH score was 17.4 (0 to 70). There was a significant correlation between the two scores (p = 0.01). The following factors were found to be correlated with a poor clinical outcome: Bado type II fracture, Jupiter type IIa fracture, fracture of the radial head, coronoid fracture, and complications requiring further surgery. Bado type II Monteggia fractures, and within this group, Jupiter type IIa fractures, are frequently associated with fractures of the radial head and the coronoid process, and should be considered as negative prognostic factors for functional long-term outcome. Patients with these types of fracture should be informed about the potential risk of functional deficits and the possible need for further surgery.

OBJECTIVES:The aim of the study was to quantify the decrease in glenohumeral stability following a global rotator cuff tear and to evaluate the effect of a decreased glenoid inclination angle through analysis of muscle force vectors in a computer model.MATERIAL AND METHODS:The lines of action of eight shoulder muscles were integrated into a standard geometric model. Muscle force magnitudes were estimated based on physiological cross-sectional area and normalized electromyographic activity. The magnitude and elevation angle of the resultant force vector was calculated at 0, 30, 60, and 90 degrees of abduction. A rotator cuff tear was simulated by reduction of the corresponding muscle force vectors.RESULTS:At 0 and 30 degrees of glenohumeral abduction a global rotator cuff tear showed a resultant force vector pointing outside the glenoid. In the computer model, decreasing the inclination angle of the glenoid by 30 degrees increased the stability in rotator cuff-deficient shoulders.CONCLUSIONS:The results of this study provide a biomechanical rationale for clinical complications of global rotator cuff tear such as superior humeral head translation. The decreased glenoid inclination simulated in the computer model may represent a biomechanical basis for the development of new operative techniques to treat global rotator cuff tears.