Advances in Orthopedics http://www.hindawi.com The latest articles from Hindawi Publishing Corporation © 2014 , Hindawi Publishing Corporation . All rights reserved. Management of Humeral and Glenoid Bone Loss in Recurrent Glenohumeral Instability Thu, 17 Jul 2014 09:59:45 +0000 http://www.hindawi.com/journals/aorth/2014/640952/ Recurrent shoulder instability and resultant glenoid and humeral head bone loss are not infrequently encountered in the population today, specifically in young, athletic patients. This review on the management of bone loss in recurrent glenohumeral instability discusses the relevant shoulder anatomy that provides stability to the shoulder joint, relevant history and physical examination findings pertinent to recurrent shoulder instability, and the proper radiological imaging choices in its workup. Operative treatments that can be used to treat both glenoid and humeral head bone loss are outlined. These include coracoid transfer procedures and allograft/autograft reconstruction at the glenoid, as well as humeral head disimpaction/humeroplasty, remplissage, humeral osseous allograft reconstruction, rotational osteotomy, partial humeral head arthroplasty, and hemiarthroplasty on the humeral side. Clinical outcomes studies reporting general results of these techniques are highlighted. Randy Mascarenhas, Jamie Rusen, Bryan M. Saltzman, Jeff Leiter, Jaskarndip Chahal, Anthony A. Romeo, and Peter MacDonald Copyright © 2014 Randy Mascarenhas et al. All rights reserved. Partial Facetectomy for Lumbar Foraminal Stenosis Tue, 08 Jul 2014 12:10:08 +0000 http://www.hindawi.com/journals/aorth/2014/534658/ Background. Several different techniques exist to address the pain and disability caused by isolated nerve root impingement. Failure to adequately decompress the lumbar foramen may lead to failed back surgery syndrome. However, aggressive treatment often causes spinal instability or may require fusion for satisfactory results. We describe a novel technique for decompression of the lumbar nerve root and demonstrate its effectiveness in relief of radicular symptoms. Methods. Partial facetectomy was performed by removal of the medial portion of the superior facet in patients with lumbar foraminal stenosis. 47 patients underwent the procedure from 2001 to 2010. Those who demonstrated neurogenic claudication without spinal instability or central canal stenosis and failed conservative management were eligible for the procedure. Functional level was recorded for each patient. These patients were followed for an average of 3.9 years to evaluate outcomes. Results. 27 of 47 patients (57%) reported no back pain and no functional limitations. Eight of 47 patients (17%) reported moderate pain, but had no limitations. Six of 47 patients (13%) continued to experience degenerative symptoms. Five of 47 patients (11%) required additional surgery. Conclusions. Partial facetectomy is an effective means to decompress the lumbar nerve root foramen without causing spinal instability. Kevin Kang, Juan Carlos Rodriguez-Olaverri, Frank Schwab, Jenifer Hashem, Afshin Razi, and Jean Pierre Farcy Copyright © 2014 Kevin Kang et al. All rights reserved. External Rotator Sparing with Posterior Acetabular Fracture Surgery: Does It Change Outcome? Sun, 06 Jul 2014 10:04:14 +0000 http://www.hindawi.com/journals/aorth/2014/520196/ This study analyses the results of the treatment with external rotator sparing approach in acetabular fractures to determine whether muscle sparing has a positive impact on functional outcome. 20 patients with a mean age of 45.9 years (range: 26–64) that had been treated for displaced acetabular fractures were included in this series. Short Musculoskeletal Function Assessment (SMFA) questionnaire and hip muscle strength measurement were done at the 24-month of follow-up period. The radiographic results at the final followup were excellent in 9 hips (45%), good in 6 hips (30%), fair in 4 hips (20%), and poor in one hip (5%) according to the criteria developed by Matta. The average SMFA score for all of the patients was 18.3 (range: 0–55.4). The mean dysfunctional and bother indexes were 17.2 and 20.6, respectively. The overall muscle strength deficit was 11.8%. The greatest loss of strength was in internal rotation. In patients with better postoperative reduction quality of acetabular fracture, peak torque, and maximum work of hip flexion, extension and also internal rotation maximum work deficit were significantly lower . Accurate initial reduction and longer postoperative muscle strengthening exercise programs seem critical to decrease postoperative hip muscle weakness after acetabular fractures. Halil Ceylan, Ozgur Selek, Murat Inanir, Omer Yonga, Bahar Odabas Ozgur, and Ahmet Y. Sarlak Copyright © 2014 Halil Ceylan et al. All rights reserved. Hip Joint Osteochondroma: Systematic Review of the Literature and Report of Three Further Cases Tue, 20 May 2014 11:41:18 +0000 http://www.hindawi.com/journals/aorth/2014/180254/ The aim of this study is to systematically review the literature with regards to surgical treatment of patients with hip joint osteochondromas, and to report our surgical management of three paediatric patients who had femoral neck or acetabular osteochondromas in association with acetabular dysplasia. We performed a systematic review using PubMed and Embase databases for all studies that reported surgical treatments for patients with peritrochanteric or acetabular osteochondroma with or without acetabular dysplasia. We also retrospectively reviewed three patients who were diagnosed with a hip osteochondroma in association with actetabular dysplasia. These patients were known to have hereditary multiple exostoses (HME). The systematic review revealed 21 studies that met our inclusion criteria. All studies were case reports and retrospective in nature and failed to conclude a uniform treatment plan. The three reported cases illustrate successful excision of hip osteochondromas and treatment of acetabular dysplasia. Early excision of hip osteochondromas might prevent acetabular dysplasia in HME patients. Routine radiographic pelvic survey at the time of diagnosis of HME is recommended for early detection of hip osteochondromas and acetabular dysplasia in these children. Asim M. Makhdom, Fan Jiang, Reggie C. Hamdy, Thierry E. Benaroch, Martin Lavigne, and Neil Saran Copyright © 2014 Asim M. Makhdom et al. All rights reserved. Radiographic Markers of Femoroacetabular Impingement: Correlation of Herniation Pit and Femoral Bump with a Positive Cross-Over Ratio Sun, 27 Apr 2014 13:23:48 +0000 http://www.hindawi.com/journals/aorth/2014/432728/ Introduction. The goal of this study was to research the association of femoral bumps and herniation pits with the overlap-ratio of the cross-over sign. Methods. Pelvic X-rays and CT-scans of 2925 patients with good assessment of the anterior and the posterior acetabular wall and absence of neutral pelvic tilt were enrolled in the investigation. Finally pelvic X-rays were assessed for the presence of a positive cross-over sign, and CT-scans for a femoral bump or a herniation pit. Additionally, if a positive cross-over sign was discovered, the overlap-ratio was calculated. Results. A femoral bump was found in 53.3% (), and a herniation pit in 27.2% () of all hips. The overlap-ratio correlated positively with the presence of a femoral bump, while a negative correlation between the overlap-ratio and the presence of a herniation pit was found. The latter was significantly more often combined with a femoral bump than without. Conclusions. We detected an increased prevalence of femoral bump with increasing overlap-ratios of the cross-over sign indicating a relation to biomechanical stress. The observed decreased prevalence of herniation pits with increasing overlap-ratios could be explained by reduced mechanical stress due to nontightened iliofemoral ligament in the presence of retroversion of the acetabulum. Max J. Scheyerer, Carol E. Copeland, Jeffrey Stromberg, Thomas Ruckstuhl, and Clément M. L. Werner Copyright © 2014 Max J. Scheyerer et al. All rights reserved. Early Clinical and Radiographic Results of Minimally Invasive Anterior Approach Hip Arthroplasty Sun, 02 Mar 2014 00:00:00 +0000 http://www.hindawi.com/journals/aorth/2014/954208/ We present a retrospective review of the early results and complications in a series of 35 consecutive patients with 43 total hip arthroplasties performed through an anterior muscle sparing minimally invasive approach. We found the early complication rates and radiographic outcomes comparable to those reported from arthroplasties performed via traditional approaches. Complications included dislocation (2%), femur fracture (2%), greater trochanteric fracture (12%), postoperative periprosthetic intertrochanteric fracture (2%), femoral nerve palsy (5%), hematoma (2%), and postoperative iliopsoas avulsion (2%). Radiographic analysis revealed average cup anteversion of , average cup abduction angle of , stem varus of , and a mean leg length discrepancy of 0.7 mm. The anterior approach to the hip is an attractive alternative to the more traditional approaches. Acceptable component placement with comparable complication rates is possible using a muscle sparing technique which may lead to faster overall recovery. Tamara Alexandrov, Elke R. Ahlmann, and Lawrence R. Menendez Copyright © 2014 Tamara Alexandrov et al. All rights reserved. Clinical Outcomes of Tibial Components with Modular Stems Used in Primary TKA Wed, 05 Feb 2014 10:03:46 +0000 http://www.hindawi.com/journals/aorth/2014/651279/ Due to the known potential for fretting and corrosion at modular junctions in orthopaedic implants, this retrospective study evaluated radiographic and clinical outcomes of 85 primary TKA patients implanted with modular stemmed tibial components and followed up for an average of 82 months. There was low incidence of tibial radiolucent lines, excellent functional outcomes, and no complications associated with stem modularity. The findings were comparable to the historical control study involving 107 TKA with a nonmodular tibial stem design. When using surface cemented tibial components combined with a constrained polyethylene bearing, modular stems appear to be a viable option for primary TKA when adequate fixation and rotational stability are maintained. Nicole Durig, Thomas Pace, Brandon Broome, Obi Osuji, and Melinda K. Harman Copyright © 2014 Nicole Durig et al. All rights reserved. Changes in Joint Gap Balances between Intra- and Postoperation in Total Knee Arthroplasty Thu, 02 Jan 2014 13:30:43 +0000 http://www.hindawi.com/journals/aorth/2014/790806/ Achieving correct soft tissue balance and preparing equal and rectangular extension and flexion joint gaps are crucial goals of TKA. Intraoperative gap balances would change postoperatively; however, changes in joint gap balances between pre- and postoperation remain unclear. To explore these changes associated with TKA, we prospectively investigated 21 posterior cruciate ligament retaining TKAs for varus knees. Intraoperative extension gap balance (iEGB) was 2.6 ± 2.0° varus versus postoperative extension gap balance (pEGB) of 0.77 ± 1.8° valgus (), while no significant difference between intraoperative flexion gap balance (iFGB) and postoperative flexion gap balance (pFGB) was observed. We also explored correlations between intraoperative and postoperative gap balances but found no significant correlations. These observations indicate that (i) surgeons should avoid excessive release of the medial soft tissue during TKA for varus knees and (ii) intraoperative gap balance may not be necessarily reflected on postoperative gap balance. Arata Nakajima, Yasuchika Aoki, Masazumi Murakami, and Koichi Nakagawa Copyright © 2014 Arata Nakajima et al. All rights reserved. Current Concepts in Robotics for the Treatment of Joint Disease Mon, 23 Dec 2013 09:43:52 +0000 http://www.hindawi.com/journals/aorth/2013/948360/ Michael A. Conditt, William L. Bargar, Justin P. Cobb, Lawrence D. Dorr, and Jess H. Lonner Copyright © 2013 Michael A. Conditt et al. All rights reserved. Cemented versus Uncemented Oxford Unicompartmental Knee Arthroplasty: Is There a Difference? Mon, 09 Dec 2013 09:31:20 +0000 http://www.hindawi.com/journals/aorth/2013/245915/ Purpose. The use of uncemented unicompartmental knee prostheses has recently increased. However, few studies on the outcomes of uncemented unicompartmental knee prostheses have been performed. The purpose of this study was to compare the outcomes of cemented and uncemented Oxford unicompartmental knee arthroplasty. Materials and Methods. This retrospective observational study evaluated the clinical and radiological outcomes of 263 medial Oxford unicompartmental prostheses (141 cemented, 122 uncemented) implanted in 235 patients. The mean follow-up was 42 months in the cemented group and 30 months in the uncemented group. Results. At the last follow-up, there were no significant differences in the clinical results or survival rates between the two groups. However, the operation time in the uncemented unicompartmental knee arthroplasty group was shorter than that in the cemented unicompartmental knee arthroplasty group. In addition, the cost of uncemented arthroplasty was greater. Conclusion. Despite the successful midterm results in the uncemented unicompartmental knee arthroplasty group, a longer follow-up period is required to determine the best fixation mode. Burak Akan, Dogac Karaguven, Berk Guclu, Tugrul Yildirim, Alper Kaya, Mehmet Armangil, and Ilker Cetin Copyright © 2013 Burak Akan et al. All rights reserved. Monoaxial Pedicle Screws Are Superior to Polyaxial Pedicle Screws and the Two Pin External Fixator for Subcutaneous Anterior Pelvic Fixation in a Biomechanical Analysis Tue, 03 Dec 2013 16:03:58 +0000 http://www.hindawi.com/journals/aorth/2013/683120/ Purpose. Comparison of monoaxial and polyaxial screws with the use of subcutaneous anterior pelvic fixation. Methods. Four different groups each having 5 constructs were tested in distraction within the elastic range. Once that was completed, 3 components were tested in torsion within the elastic range, 2 to torsional failure and 3 in distraction until failure. Results. The pedicle screw systems showed higher stiffness (4.008 ± 0.113 Nmm monoaxial, 3.638 ± 0.108 Nmm Click-x; 3.634 ± 0.147 Nmm Pangea) than the exfix system (2.882 ± 0.054 Nmm) in distraction. In failure testing, monoaxial pedicle screw system was stronger (360 N) than exfixes (160 N) and polyaxial devices which failed if distracted greater than 4 cm (157 N Click-x or 138 N Pangea). The exfix had higher peak torque and torsional stiffness than all pedicle systems. In torsion, the yield strengths were the same for all constructs. Conclusion. The infix device constructed with polyaxial or monoaxial pedicle screws is stiffer than the 2 pin external fixator in distraction testing. In extreme cases, the use of reinforcement or monoaxial systems which do not fail even at 360 N is a better option. In torsional testing, the 2 pin external fixator is stiffer than the pedicle screw systems. Rahul Vaidya, Ndidi Onwudiwe, Matthew Roth, and Anil Sethi Copyright © 2013 Rahul Vaidya et al. All rights reserved. Union Rate on Hinge Side after Open-Door Laminoplasty Using Maxillofacial Titanium Miniplate Tue, 26 Nov 2013 10:23:44 +0000 http://www.hindawi.com/journals/aorth/2013/767343/ Background. One of the important complications of open-door laminoplasty is a premature laminoplasty closure. In order to prevent premature laminoplasty closure many techniques have been described and a titanium miniplate is one of the instruments to maintain cervical canal expansion. This study was performed to evaluate the effectiveness of titanium miniplates on the union rate for open-door laminoplasty. Materials and Methods. We performed open-door laminoplasty in 68 levels of fourteen patients using maxillofacial titanium miniplates. Axial computed tomography scans were obtained at 6 months postoperatively to evaluate the union rates of the hinge side. The Japanese Orthopedic Association (JOA) score was used to compare the clinical outcomes before and after surgery. Results. Computed tomography scan data was available on 68 levels in 14 patients. There were no premature closures of the hinge or miniplate dislodgements. The union rate on the hinge side was 70.5% (48/68). The mean JOA score increased significantly from 7.0 before surgery to 10.2, 12.2, and 13.0 after surgery at 1, 3, and 6 months, respectively. Conclusion. Open-door laminoplasty using maxillofacial titanium miniplates can provide union rates comparable to other techniques. It can maintain canal expansion without failures, dislodgements, and premature closures. Koopong Siribumrungwong, Theerasan Kiriratnikom, and Boonsin Tangtrakulwanich Copyright © 2013 Koopong Siribumrungwong et al. All rights reserved. Distal Femur Allograft Prosthetic Composite Reconstruction for Short Proximal Femur Segments following Tumor Resection Sun, 17 Nov 2013 15:12:31 +0000 http://www.hindawi.com/journals/aorth/2013/397456/ Short metaphyseal segments remaining after distal femoral tumor resection pose a unique challenge. Limb sparing options include a short stemmed modular prosthesis, total endoprosthetic replacement, cross-pin fixation to a custom implant, and allograft prosthetic composite reconstruction (APC). A series of patients with APC reconstruction were evaluated to determine functional and radiologic outcome and complication rates. Twelve patients were retrospectively identified who had a distal femoral APC reconstruction between 1994 and 2007 to salvage an extremity with a segment of remaining bone that was less than 20 centimeters in length. Seventeen APC reconstructions were performed in twelve patients. Eight were primary procedures and nine were revision procedures. Average f/u was 89 months. Twelve APC reconstructions (71%) united and five (29%) were persistent nonunions. At most recent followup 10 patients (83%) had a healed APC which allowed WBAT. One pt (8%) had an amputation and one pt (8%) died prior to union. Average time to union was 19 months. Four pts (33%) or five APC reconstructions (29%) required further surgery to obtain a united reconstruction. Although Distal Femoral APC reconstruction has a high complication rate, a stable reconstruction was obtained in 83% of patients. Bryan S. Moon, Nathan F. Gilbert, Christopher P. Cannon, Patrick P. Lin, and Valerae O. Lewis Copyright © 2013 Bryan S. Moon et al. All rights reserved. Cement Removal from the Femur Using the ROBODOC System in Revision Total Hip Arthroplasty Tue, 22 Oct 2013 15:42:58 +0000 http://www.hindawi.com/journals/aorth/2013/347358/ Introduction. The perforation and fracture of the femur during the removal of bone cement in revision total hip arthroplasty (THA) are serious complications. The ROBODOC system has been designed to selectively remove bone cement from the femoral canal, but results have not been reported yet. The purpose of our study was to evaluate the clinical and radiographic results of revision THA using the ROBODOC system for cement removal. Materials and Methods. The subjects comprised 19 patients who underwent revision THA using the ROBODOC system. The minimum duration of follow-up was 76 months (median, 109 months; range, 76–150 months). The extent of remaining bone cement on postoperative radiography, timing of weight bearing, and the complications were evaluated. Results. The mean Merle d’Aubigne and Postel score increased from 10 points preoperatively to 14 points by final follow-up. Bone cement was completely removed in all cases. Full weight bearing was possible within 1 week after surgery in 9 of the 19 cases and within 2 months in all remaining cases. No instances of perforation or fracture of the femur were encountered. Conclusions. Bone cement could be safely removed using the ROBODOC system, and no serious complications occurred. Full weight bearing was achieved early in the postoperative course because of circumferential preservation of the femoral cortex. Mitsuyoshi Yamamura, Nobuo Nakamura, Hidenobu Miki, Takashi Nishii, and Nobuhiko Sugano Copyright © 2013 Mitsuyoshi Yamamura et al. All rights reserved. Elbow Dislocations: A Review Ranging from Soft Tissue Injuries to Complex Elbow Fracture Dislocations Mon, 21 Oct 2013 15:37:22 +0000 http://www.hindawi.com/journals/aorth/2013/951397/ This review on elbow dislocations describes ligament and bone injuries as well as the typical injury mechanisms and the main classifications of elbow dislocations. Current treatment concepts of simple, that is, stable, or complex unstable elbow dislocations are outlined by means of case reports. Special emphasis is put on injuries to the medial ulnar collateral ligament (MUCL) and on posttraumatic elbow stiffness. Carsten Englert, Johannes Zellner, Michael Koller, Michael Nerlich, and Andreas Lenich Copyright © 2013 Carsten Englert et al. All rights reserved. Anterior Glenohumeral Instability: Classification of Pathologies of Anteroinferior Labroligamentous Structures Using MR Arthrography Wed, 02 Oct 2013 13:49:45 +0000 http://www.hindawi.com/journals/aorth/2013/473194/ We examined labroligamentous structures in unstable anteroinferior glenohumeral joints using MR arthrography (MRA) to demonstrate that not all instabilities are Bankart lesions. We aimed to show that other surgical protocols besides classic Bankart repair are appropriate for labroligamentous lesions. The study included 35 patients (33 males and 2 females; mean age: 30.2; range: 18 to 57 years). MRA was performed in all patients. The lesions underlying patients’ instability such as Bankart, anterior labral periosteal sleeve avulsion (ALPSA), and Perthes lesions were diagnosed by two radiologists. MRA yielded 16 diagnoses of Bankart lesions, 5 of ALPSA lesions, and 14 of Perthes lesions. Albeit invasive, MRA seems to be a more reliable and accurate diagnostic imaging modality for the classification and treatment of instabilities compared to standard MRI. Serhat Mutlu, Mahir Mahıroğullari, Olcay Güler, Bekir Yavuz Uçar, Harun Mutlu, Güner Sönmez, and Hakan Mutlu Copyright © 2013 Serhat Mutlu et al. All rights reserved. Protocol for Evaluation of Robotic Technology in Orthopedic Surgery Thu, 19 Sep 2013 11:03:31 +0000 http://www.hindawi.com/journals/aorth/2013/194683/ In recent years, robots have become commonplace in surgical procedures due to their high accuracy and repeatability. The Acrobot Sculptor is an example of such a robot that can assist with unicompartmental knee replacement. In this study, we aim to evaluate the accuracy of the robot (software and hardware) in a clinical setting. We looked at (1) segmentation by comparing the segmented data from Sculptor software to other commercial software, (2) registration by checking the inter- and intraobserver repeatability of selecting set points, and finally (3) sculpting ( cases) by evaluating the achieved implant position and orientation relative to that planned. The results from segmentation and registration were found to be accurate. The highest error was observed in flexion extension orientation of femoral implant (°). Mean compound rotational and translational errors for both components were  mm and ° for tibia and  mm and ° for the femur. The results from all processes used in Acrobot were small. Validation of robot in clinical settings is highly vital to ensure a good outcome for patients. It is therefore recommended to follow the protocol used here on other available similar products. Milad Masjedi, Zahra Jaffry, Simon Harris, and Justin Cobb Copyright © 2013 Milad Masjedi et al. All rights reserved. Accuracy of Implant Placement Utilizing Customized Patient Instrumentation in Total Knee Arthroplasty Mon, 16 Sep 2013 11:12:26 +0000 http://www.hindawi.com/journals/aorth/2013/891210/ Customized patient instrumentation (CPI) combines preoperative planning with customized cutting jigs to position and align implants during total knee arthroplasty (TKA). We compared postoperative implant alignment of patients undergoing surgery with CPI to traditional TKA instrumentation for accuracy of implant placement. Twenty-five consecutive TKAs using CPI were analyzed. Preoperative CT scans of the lower extremities were segmented using a computer program. Limb alignment and mechanical axis were computed. Virtual implantation of computer-aided design models was done. Postoperative coronal and sagittal view radiographs were obtained. Using 3D image-matching software, relative positions of femoral and tibial implants were determined. Twenty-five TKAs implanted using traditional instrumentation were also analyzed. For CPI, difference in alignment from the preoperative plan was calculated. In the CPI group, the mean absolute difference between the planned and actual femoral placements was 0.67° in the coronal plane and 1.2° in the sagittal plane. For tibial alignment, the mean absolute difference was 0.9° in the coronal plane and 1.3° in the sagittal plane. For traditional instrumentation, difference from ideal placement for the femur was 1.5° in the coronal plane and 2.3° in the sagittal plane. For the tibia, the difference was 1.8° in the coronal plane. CPI achieved accurate implant positioning and was superior to traditional TKA instrumentation. William D. Bugbee, Hideki Mizu-uchi, Shantanu Patil, and Darryl D'Lima Copyright © 2013 William D. Bugbee et al. All rights reserved. Minimally Invasive Sacroiliac Joint Fusion: One-Year Outcomes in 40 Patients Tue, 13 Aug 2013 16:29:39 +0000 http://www.hindawi.com/journals/aorth/2013/536128/ Background. SI joint pain is difficult to diagnose due to overlapping symptoms of the lumbar spine, and until recently, treatment options have been limited. The purpose of this retrospective study is to report on the safety and effectiveness of MIS SI joint arthrodesis using a series of triangular, porous plasma coated implants in patients refractory to conservative care. Methods. We report on the first 40 consecutive patients with one-year follow-up data that underwent MIS SI joint fusion with the iFuse Implant System (SI-BONE, Inc., San Jose, CA) by a single surgeon. Medical charts were reviewed for demographics, perioperative metrics, complications, pain scores, and satisfaction. Results. Mean age was 58 years (range 30–81) and 75% of patients were female. Postoperative complications were minimal and included transient trochanteric bursitis (5%), facet joint pain (20%), and new low back pain (2.5%). There were no reoperations at one year. Mean pain score improved from 8.7 (1.5 SD) at baseline to 0.9 (1.6) at 12 months, a 7.8-point improvement (). Patient satisfaction was very high. Conclusions. The results of this case series reveal that MIS SI joint fusion using the iFuse Implant System is a safe and effective treatment option in carefully selected patients. Donald Sachs and Robyn Capobianco Copyright © 2013 Donald Sachs and Robyn Capobianco. All rights reserved. Posterior Transpedicular Dynamic Systems in the Treatment of Chronic Lumbar Instability Wed, 07 Aug 2013 09:17:15 +0000 http://www.hindawi.com/journals/aorth/2013/432520/ Ali Fahir Ozer, Vijay K. Goel, Ahmet Alanay, Mehdi Sasani, Tunc Oktenoglu, and Deniz Erbulut Copyright © 2013 Ali Fahir Ozer et al. All rights reserved. The Comprehensive Biomechanics and Load-Sharing of Semirigid PEEK and Semirigid Posterior Dynamic Stabilization Systems Sun, 04 Aug 2013 13:25:57 +0000 http://www.hindawi.com/journals/aorth/2013/745610/ Alternatives to conventional rigid fusion have been proposed for several conditions related to degenerative disc disease when nonoperative treatment has failed. Semirigid fixation, in the form of dynamic stabilization or PEEK rods, is expected to provide compression under loading as well as an intermediate level of stabilization. This study systematically examines both the load-sharing characteristics and kinematics of these two devices compared to the standard of internal rigid fixators. Load-sharing was studied by using digital pressure films inserted between an artificially machined disc and two loading fixtures. Rigid rods, PEEK rods, and the dynamic stabilization system were inserted posteriorly for stabilization. The kinematics were quantified on ten, human, cadaver lumbosacral spines (L3-S1) which were tested under a pure bending moment, in flexion-extension, lateral bending, and axial rotation. The magnitude of load transmission through the anterior column was significantly greater with the dynamic device compared to PEEK rods and rigid rods. The contact pressures were distributed more uniformly, throughout the disc with the dynamic stabilization devices, and had smaller maximum point-loading (pressures) on any particular point within the disc. Kinematically, the motion was reduced by both semirigid devices similarly in all directions, with slight rigidity imparted by a lateral interbody device. D. K. Sengupta, Brandon Bucklen, Paul C. McAfee, Jeff Nichols, Raghavendra Angara, and Saif Khalil Copyright © 2013 D. K. Sengupta et al. All rights reserved. Vacuum Assisted Closure Therapy versus Standard Wound Therapy for Open Musculoskeletal Injuries Wed, 26 Jun 2013 13:07:28 +0000 http://www.hindawi.com/journals/aorth/2013/245940/ Background. This study was performed to evaluate the results of vacuum assisted wound therapy in patients with open musculoskeletal injuries. Study Design and Setting. Prospective, randomized, and interventional at tertiary care hospital, from 2011 to 2012. Materials and Methods. 30 patients of open musculoskeletal injuries underwent randomized trial of vacuum assisted closure therapy versus standard wound therapy around the upper limb and lower limb. Mean patient age was years (range, 18 to 76 years). Necrotic tissues were debrided before applying VAC therapy. Dressings were changed every 3 or 4 days. For standard wound therapy, debridement followed by daily dressings was done. Data Management and Statistical Analysis. The results obtained were subjected to statistical analysis. Results. The size of soft tissue defects reduced more than 5 mm to 25 mm after VAC (mean decrease of 26.66%), whereas in standard wound therapy, reduction in wound size was less than 5 mm. A free flap was needed to cover exposed bone and tendon in one case in standard wound therapy group. No major complication occurred that was directly attributable to treatment. Conclusion. Vacuum assisted wound therapy was found to facilitate the rapid formation of healthy granulation tissue on open wounds in the upper limb and lower limb, thus to shorten healing time and minimize secondary soft tissue defect coverage procedures. Kushagra Sinha, Vijendra D. Chauhan, Rajesh Maheshwari, Neena Chauhan, Manu Rajan, and Atul Agrawal Copyright © 2013 Kushagra Sinha et al. All rights reserved. Robotic Assistance Enables Inexperienced Surgeons to Perform Unicompartmental Knee Arthroplasties on Dry Bone Models with Accuracy Superior to Conventional Methods Wed, 19 Jun 2013 08:43:29 +0000 http://www.hindawi.com/journals/aorth/2013/481039/ Robotic systems have been shown to improve unicompartmental knee arthroplasty (UKA) component placement accuracy compared to conventional methods when used by experienced surgeons. We aimed to determine whether inexperienced UKA surgeons can position components accurately using robotic assistance when compared to conventional methods and to demonstrate the effect repetition has on accuracy. Sixteen surgeons were randomised to an active constraint robot or conventional group performing three UKAs over three weeks. Implanted component positions and orientations were compared to planned component positions in six degrees of freedom for both femoral and tibial components. Mean procedure time decreased for both robot (37.5 mins to 25.7 mins) () and conventional (33.8 mins to 21.0 mins) () groups by attempt three indicating the presence of a learning curve; however, neither group demonstrated changes in accuracy. Mean compound rotational and translational errors were lower in the robot group compared to the conventional group for both components at all attempts for which rotational error differences were significant at every attempt. The conventional group’s positioning remained inaccurate even with repeated attempts although procedure time improved. In comparison, by limiting inaccuracies inherent in conventional equipment, robotic assistance enabled surgeons to achieve precision and accuracy when positioning UKA components irrespective of their experience. Monil Karia, Milad Masjedi, Barry Andrews, Zahra Jaffry, and Justin Cobb Copyright © 2013 Monil Karia et al. All rights reserved. Retrospective Review of Pectoralis Major Ruptures in Rodeo Steer Wrestlers Thu, 06 Jun 2013 11:47:48 +0000 http://www.hindawi.com/journals/aorth/2013/987910/ Background. Pectoralis major tendon ruptures have been reported in the literature as occupational injuries, accidental injuries, and sporting activities. Few cases have been reported with respect to rodeo activities. Purpose. To describe a series of PM tendon ruptures in professional steer wrestlers. Study Design. Case series, level of evidence, 4. Methods. A retrospective analysis of PM ruptures in a steer wrestling cohort was performed. Injury data between 1992 and 2008 were reviewed using medical records from the University of Calgary Sport Medicine Center. Results. Nine cases of pectoralis major ruptures in professional steer wrestlers were identified. Injuries occurred during the throwing phase of the steer or while breaking a fall. All athletes reported unexpected or abnormal behavior of the steer that contributed to the mechanism of injury. Seven cases were surgically repaired, while two cases opted for nonsurgical intervention. Eight cases reported successful return to competition following the injury. Conclusion. Steer wrestlers represent a unique cohort of PM rupture case studies. Steer wrestling is a demanding sport that involves throwing maneuvers that may predispose the muscle to rupture. All cases demonstrated good functional outcomes regardless of surgical or non-surgical treatment. Breda H. F. Lau, Dale J. Butterwick, Mark R. Lafave, and Nicholas G. Mohtadi Copyright © 2013 Breda H. F. Lau et al. All rights reserved. Adult's Degenerative Scoliosis: Midterm Results of Dynamic Stabilization without Fusion in Elderly Patients—Is It Effective? Sun, 26 May 2013 11:53:07 +0000 http://www.hindawi.com/journals/aorth/2013/365059/ Study Design. A retrospective study. Purpose. Posterolateral fusion with pedicle screw instrumentation used for degenerative lumbar scoliosis can lead to several complications. In elderly patients without sagittal imbalance, dynamic stabilization could represent an option to avoid these adverse events. Methods. 57 patients treated by dynamic stabilization without fusion were included. All patients had degenerative lumbar de novo scoliosis (average Cobb angle 17.2°), without sagittal imbalance, associated in 52 cases (91%) with vertebral canal stenosis and in 24 (42%) with degenerative spondylolisthesis. Nineteen patients (33%) had previously undergone lumbar spinal surgery. Results. At an average followup of 77 months, clinical results improved with statistical significance. Scoliosis Cobb angle was 17.2° (range, 12° to 38°) before surgery and 11.3° (range, 4° to 26°) at last follow-up. In the patients with associated spondylolisthesis, anterior vertebral translation was 19.5% (range, 12% to 27%) before surgery, 16.7% (range, 0% to 25%) after surgery, and 17.5% (range, 0% to 27%) at followup. Complications incidence was low (14%), and few patients required revision surgery (4%). Conclusions. In elderly patients with mild degenerative lumbar scoliosis without sagittal imbalance, pedicle screw-based dynamic stabilization is an effective option, with low complications incidence, granting curve stabilization during time and satisfying clinical results. Mario Di Silvestre, Francesco Lolli, Tiziana Greggi, Francesco Vommaro, and Andrea Baioni Copyright © 2013 Mario Di Silvestre et al. All rights reserved. Dynamic Stabilisation in the Treatment of Degenerative Disc Disease with Modic Changes Mon, 20 May 2013 14:47:55 +0000 http://www.hindawi.com/journals/aorth/2013/806267/ Objective. Posterior dynamic stabilization is an effective alternative to fusion in the treatment of chronic instability and degenerative disc disease (DDD) of the lumbar spine. This study was undertaken to investigate the efficacy of dynamic stabilization in chronic degenerative disc disease with Modic types 1 and 2. Modic types 1 and 2 degeneration can be painful. Classic approach in such cases is spine fusion. We operated 88 DDD patients with Modic types 1 and 2 via posterior dynamic stabilization. Good results were obtained after 2 years of followup. Methods. A total of 88 DDD patients with Modic types 1 and 2 were selected for this study. The patients were included in the study between 2004 and 2010. All of them were examined with lumbar anteroposterior (AP) and lateral X-rays. Lordosis of the lumbar spine, segmental lordosis, and ratio of the height of the intervertebral disc spaces (IVSs) were measured preoperatively and at 3, 12, and 24 months after surgery. Magnetic resonance imaging (MRI) analysis was carried out, and according to the data obtained, the grade of disc degeneration was classified. The quality of life and pain scores were evaluated by visual analog scale (VAS) score and Oswestry Disability Index (ODI) preoperatively and at 3, 12, and 24 months after surgery. Appropriate statistical method was chosen. Results. The mean 3- and 12-month postoperative IVS ratio was significantly greater than that of the preoperative group (). However, the mean 1 and 2 postoperative IVS ratio was not significantly different (). Furthermore, the mean preoperative and 1 and 2 postoperative angles of lumbar lordosis and segmental lordosis were not significantly different (). The mean VAS score and ODI, 3, 12, and 24 months after surgery, decreased significantly, when compared with the preoperative scores in the groups (). Conclusion. Dynamic stabilization in chronic degenerative disc disease with Modic types 1 and 2 was effective. Olcay Eser, Cengiz Gomleksiz, Mehdi Sasani, Tunc Oktenoglu, Ahmet Levent Aydin, Yaprak Ataker, Tuncer Suzer, and Ali Fahir Ozer Copyright © 2013 Olcay Eser et al. All rights reserved. A Perspective on Robotic Assistance for Knee Arthroplasty Tue, 30 Apr 2013 11:26:24 +0000 http://www.hindawi.com/journals/aorth/2013/970703/ Knee arthroplasty is used to treat patients with degenerative joint disease of the knee to reduce pain and restore the function of the joint. Although patient outcomes are generally quite good, there are still a number of patients that are dissatisfied with their procedures. Aside from implant design which has largely become standard, surgical technique is one of the main factors that determine clinical results. Therefore, a lot of effort has gone into improving surgical technique including the use of computer-aided surgery. The latest generation of orthopedic surgical tools involves the use of robotics to enhance the surgeons’ abilities to install implants more precisely and consistently. This review presents an evolution of robot-assisted surgical systems for knee replacement with an emphasis on the clinical results available in the literature. Ever since various robotic-assistance systems were developed and used clinically worldwide, studies have demonstrated that these systems are as safe as and more accurate than conventional methods of manual implantation. Robotic surgical assistance will likely result in improved surgical technique and improved clinical results. Nathan A. Netravali, Feimo Shen, Youngbae Park, and William L. Bargar Copyright © 2013 Nathan A. Netravali et al. All rights reserved. Intervertebral Disc Rehydration after Lumbar Dynamic Stabilization: Magnetic Resonance Image Evaluation with a Mean Followup of Four Years Mon, 29 Apr 2013 13:40:29 +0000 http://www.hindawi.com/journals/aorth/2013/437570/ Objective. To compare the clinical and radiographic outcomes in patients of different ages who underwent the Dynesys stabilization. Methods. This retrospective study included 72 patients (mean age 61.4 years) with one- or two-level lumbar spinal stenosis who underwent laminectomy and the Dynesys (Zimmer Spine, Minneapolis) dynamic stabilization system. Thirty-seven patients were younger than 65-year old while the other 35 were older. Mean followup was 46.7 months. Pre- and postoperative radiographic and clinical evaluations were analyzed. Results. The mean calibrated disc signal (CDS) at the index level was significantly improved from preoperatively to postoperatively (). Screw loosening occurred in 22.2% of patients and 5.1% of screws. The improvement in CDS at index level was seen to be significant in younger patients but not in older patients. Overall, the mean visual analogue scale (VAS) of back pain, VAS of leg pain, and the Oswestry disability index (ODI) scores improved significantly after operation. There were no significant differences in pre- and postoperative VAS and ODI and screw loosening rates between the younger and older patients. Conclusions. There is significant clinical improvement after laminectomy and dynamic stabilization for symptomatic lumbar spinal stenosis. Intervertebral disc rehydration was seen in younger patients. Li-Yu Fay, Jau-Ching Wu, Tzu-Yun Tsai, Tsung-Hsi Tu, Ching-Lan Wu, Wen-Cheng Huang, and Henrich Cheng Copyright © 2013 Li-Yu Fay et al. All rights reserved. Dynamic Stabilization for Challenging Lumbar Degenerative Diseases of the Spine: A Review of the Literature Mon, 15 Apr 2013 09:29:48 +0000 http://www.hindawi.com/journals/aorth/2013/753470/ Fusion and rigid instrumentation have been currently the mainstay for the surgical treatment of degenerative diseases of the spine over the last 4 decades. In all over the world the common experience was formed about fusion surgery. Satisfactory results of lumbar spinal fusion appeared completely incompatible and unfavorable within years. Rigid spinal implants along with fusion cause increased stresses of the adjacent segments and have some important disadvantages such as donor site morbidity including pain, wound problems, infections because of longer operating time, pseudarthrosis, and fatigue failure of implants. Alternative spinal implants were developed with time on unsatisfactory outcomes of rigid internal fixation along with fusion. Motion preservation devices which include both anterior and posterior dynamic stabilization are designed and used especially in the last two decades. This paper evaluates the dynamic stabilization of the lumbar spine and talks about chronologically some novel dynamic stabilization devices and thier efficacies. Tuncay Kaner and Ali Fahir Ozer Copyright © 2013 Tuncay Kaner and Ali Fahir Ozer. All rights reserved. Comparison of Conventional Polyethylene Wear and Signs of Cup Failure in Two Similar Total Hip Designs Thu, 11 Apr 2013 09:53:53 +0000 http://www.hindawi.com/journals/aorth/2013/710621/ Multiple factors have been identified as contributing to polyethylene wear and debris generation of the acetabular lining. Polyethylene wear is the primary limiting factor in the functional behavior and consequent longevity of a total hip arthroplasty (THA). This retrospective study reviewed the clinical and radiographic data of 77 consecutive THAs comparing in vivo polyethylene wear of two similar acetabular cup liners. Minimum follow-up was 7 years (range 7–15). The incidence of measurable wear in a group of machined liners sterilized with ethylene oxide and composed of GUR 1050 stock resin was significantly higher (61%) than the compression-molded, GUR 1020, O2-free gamma irradiation sterilized group (24%) . Clinically, at a 9-year average followup, both groups had comparable HHS scores and incidence of thigh or groin pain, though the machined group had an increased incidence of osteolysis and annual linear wear rate. Thomas B. Pace, Kevin C. Keith, Estefania Alvarez, Rebecca G. Snider, Stephanie L. Tanner, and John D. DesJardins Copyright © 2013 Thomas B. Pace et al. All rights reserved.