Percutaneous pedicle screw instrumentation

Minimally invasive fusion techniques for degenerative lumbar pathology commonly involve the placement of pedicle screws. Percutaneous placement of these screws allows the surgeon to minimize soft tissue trauma, improving postoperative recovery for patients. This review will cover the indications and techniques for percutaneous pedicle screw instrumentation of the lumbar spine, and will highlight the advantages and potential contraindications to using percutaneous instrumentation.     

Retrograde percutaneous nephrostomy

Retrograde percutaneous nephrostomy puncture to aid in stone removal is a safe and acceptable alternative to antegrade techniques. For urologists with expertise in endoscopic instrumentation and technique, it is easy to learn and does not require the presence of a skilled interventional radiologist. The advantages of the technique are that it can be performed in a non-dilated collecting system and can result in more accurate and less traumatic puncture. We have found it difficult to use in the presence of staghorn calculi filling the kidney, and its application is obviously limited if access to the lower urinary tract and ureter cannot be obtained. If the technique is unsuccessful, it does not preclude or complicate immediate antegrade percutaneous or open stone removal.     

微创术治疗腰椎间盘突出症研究现状

以内窥镜技术和影像技术为基础的微创术治疗腰椎间盘突出症(lumbar disc herniation,LDH)进展迅速,它的开展减少了手术创伤和患者痛苦,比传统手术有很多优点,但适应证相对狭窄,尚不能取代传统手术,如何操作规范扩大适应证并解决腰椎重建等诸多方面是其今后突破的方向。现从微创治疗LDH的经皮穿刺技术和內镜、内窥镜技术两大方面综述其研究现状。     

A simplified technique for laparoscopic jejunostomy and gastrostomy tube placement

BACKGROUND: Percutaneous endoscopic gastrostomy and jejunostomy tube placement have long been considered the standard for supplying enteral nutrition when oral intake is not possible. Both have well-documented roles and limitations and are associated with a higher than generally appreciated incidence of aspiration. A distally placed tube in the jejunum decreases the chance of this morbid complication. Additionally, when percutaneous endoscopic gastrostomy is indicated but cannot be done for technical reasons, a minimally invasive alternative is desirable. METHODS: In prior series, the techniques suggested for laparoscopic enteral access have characteristics that are either difficult for the average surgeon to duplicate, or use nonstandard anchoring techniques of the bowel to the abdominal wall. A simple, laparoscopically directed, percutaneous technique utilizing cost-effective appliances is described, and suggested indications are outlined. RESULTS: This technique has been successfully applied in 46 patients with minimal complications. CONCLUSIONS: A simplified technique for laparoscopic jejunostomy and gastrostomy tube placement is described. This has been successfully deployed in 46 patients with minimal morbidity. The procedure lessens the need for sophisticated suturing skills and duplicates standard small bowel to abdominal wall fixation methods.     

Diverticular calculi of the kidney calices--extracorporeal shockwave lithotripsy, percutaneous extraction or open surgery

The incidence of caliceal diverticula, mostly found on routine excretory urography, is very low. The indications for treatment include chronic or recurrent pyelonephritis, pain, gross hematuria and renal damage. There is controversy as to which treatment is best: extracorporeal shock-wave lithotripsy (ESWL), percutaneous techniques, or traditional open surgery. Since 1984, 27 patients with 28 caliceal diverticula calculi have been treated. Ten patients underwent ESWL, 13 patients percutaneous treatment, and 4 patients open surgery. The success rates as far as a stone-free status is concerned were: 1 patient (ESWL), 10 (percutaneous), and 4 (open surgery). There were no complications due to ESWL or open surgical treatment. Direct traumata such as severe bleeding in two and hydrothorax in one patient occurred during the training phase of the percutaneous techniques. Due to the low complication rate, non-invasive ESWL treatment should be tried first. The indications for percutaneous removal of calculi in caliceal diverticula depend on two aspects: it should be possible to puncture the caliceal diverticula via by a short parenchymal route coaxial to the axis of the calix and, if the intercostal approach is used, a pleural lesion must be excluded. If these requirements cannot be fulfilled, open surgical treatment should be performed, especially if the diverticula are located in the upper and anterior part of the kidney.     

Perkutane dorsale Instrumentierung der thorakolumbalen Wirbelsäule

Minimally invasive percutaneous instrumentations are increasingly being used for stabilization of thoracolumbar fractures, mainly due to the advantages of reduced soft tissue damage. While percutaneous instrumentation can be generally used in less displaced fractures, it remains controversial whether such techniques should also be performed in patients with severe fracture dislocation. This includes patients with severe traumatic kyphosis and/or dislocation in the coronar plane, particularly in concomitant neurological deficits that require additional decompression surgery. Here we show the different indirect fracture reduction techniques in three cases with severe fracture dislocation and discuss the use of percutaneous stabilization techniques in combination with an additional midline approach for decompressing laminectomy.     

T-Pin for distal radius fracture

Distal radius fractures are among the most common fractures treated by orthopedic surgeons. Numerous techniques have been devised to address these fractures and the factors associated with these injuries. The T-Pin (Union Surgical, LLC, Philadelphia, PA) is a novel instrumentation designed to use standard percutaneous techniques in the treatment of extra-articular distal radius fractures. The T-Pin allows for early active range of motion, as well as earlier return to functional activities. This article discusses the instrumentation, the techniques of insertion and extraction, and postoperative care.     

Techniques of internal fixation for degenerative conditions of the lumbar spine

The indications and techniques for internal fixation of the lumbar spine in degenerative conditions have changed drastically since internal fixation was first applied to the spine almost 100 years ago. Anterior instrumentation and fusion may be used for repair of pseudarthrosis after posterolateral fusion; symptomatic lumbar scoliosis associated with degenerative disc disease; late pain secondary to posttraumatic kyphosis; postlaminectomy instability; and lumbar pain secondary to thoracolumbar kyphosis. Posterior instrumentation and fusion has been performed with Luque instrumentation over 3-4 levels in cases of multilevel instability. Combined anterior and posterior instrumentation and fusion are required for lumbosacral fusion in lumbar scoliosis with degenerative disease, and surgical correction of postsurgical lumbar kyphosis (flat-back syndrome). The techniques are demanding but with attention to detail can be performed with acceptably low-complication rates.     

Percutaneous instrumentation of the thoracic and lumbar spine

The development of percutaneous instrumentation systems has been a significant milestone in the ability of surgeons to perform complex spinal procedures through minimally invasive approaches. These systems rely on cannulated screws or portal systems and using intraoperative imaging to allow accurate placement of the spinal implants without a full traditional exposure of the spine. This article reviews the operative concepts and techniques used to place percutaneous instrumentation in the thoracolumbar spine.     

Percutaneous endopyelotomy

Percutaneous endopyelotomy, introduced over 15 years ago, is a well-established alternative to open operative pyeloplasty for management of ureteropelvic junction (UPJ) obstruction. Although several variations of the technique have been described, the goal in all cases is to develop a full thickness incision though the obstructing proximal uretra that extends out to the peripyeloureteral fat and heals over an internal stent. Though a percutaneous endopyelotomy can be considered for almost any patient with primary or secondary UPJ obstruction, it is particularly valuable in the setting of upper tract stones that can then be managed simultaneously. This article reviews the indications, techniques, and outcomes of percutaneous endopyelotomy.     

Winkelstabile Plattenfixation an Wirbelsäule und Becken

Fixed-angle implants are becoming increasingly important in trauma surgery. Besides indications generally accepted in surgery on the limbs, the question of their use in spine and pelvis surgery is discussed. Whereas anatomical preformed fixed-angle implants for pelvis surgery are not available commercially from the industry, several different angle-stable implants have been created for the anterior instrumentation of spinal injuries, all of which can be inserted in minimally invasive procedures. In cervical injuries the advantage of fixed-angle plate systems over conventional plates, is the monocortical fixation of the screws; from the biomechanical point of view, however, in the majority of fractures they do not lead to a higher fusion rate. In the treatment of thoracic and lumbar spine injuries fixed-angle implants have to be suitable for insertion by endoscopic/minimally invasive techniques. Nevertheless, adequate fusion cannot be expected without correct patient selection and detailed analysis of the fracture type.     

Minimalinvasive Chevron- und Akinostetomie: Muss man jetzt umsteigen?

Percutaneous osteotomies for the treatment of forefoot deformities have become increasingly popular in recent years. The main advantage is less soft tissue damage and aesthetic benefits. The disadvantage is the lack of visualization of the surgical field. Therefore, a precise anatomical knowledge and understanding of these techniques are required.The initial procedures of percutaneous hallux valgus surgery had a high complication rate due to limited technical capabilities, designs of osteotomies, and osteosyntheses used. The combination of established procedures, indications, and percutaneous techniques has been able to significantly advance the techniques. Even severe deformities can be corrected by the modified osteosynthesis of minimally invasive Chevron- and Akinosteotomy while preserving the soft tissue mantle.MethodAfter implementation of minimally invasive Chevron and Akinosteotomy, we evaluated the first 93 patients from the first 12 months with regard to operation time, radiation exposure and complication rate and compared them with conventional scarf and akinosteotomy.ResultsWhile a learning curve cannot be avoided, this relates particularly to operative times and radiation exposure. It was shown that the modified screw osteosynthesis and less the percutaneous osteotomy is the real challenge. With appropriate courses and training on the cadaver, complications can be avoided.SummaryFears of increased iatrogenic tendon, nerve, and vascular injuries during the learning curve have not been confirmed. In the meantime, the minimally invasive chevron and akinosteotomy (MICA) could develop into the standard procedure for the correction of moderate to severe hallux valgus deformities in our clinic. It is a safe and reproducible procedure.     

Treatment of ureteral stone disease: the role of ESWL and endourology

Summary In recent years, extracorporeal shockwave lithotripsy (ESWL) has proved a safe and easily reproducible method for the treatment of calculi in the upper urinary tract above the iliac crest. Current indications for ESWL as single therapy encompass approximately 60%–70% of all stones. The use of endourological methods as auxiliary procedures can enhance the range of indications to 95% of all renal stones and 85% of all ureteral stones. In the last year, 1340 patients have been successfully treated for urinary calculi at our department. Evaluation of all stone cases shows that ESWL alone, ESWL combined with percutaneous techniques, or percutaneous techniques alone were performed on 93% of all patients. Only 7% of patients had to undergo open surgical treatment, 1% for renal stones and 15% for ureteral stones. Ureteral stones are still among the problem stones for ESWL, in many cases requiring time-consuming combined procedures with either of the percutaneous methods. Furthermore, ureteral obstruction caused by stone particles as a complication after ESWL-treatment of large renal stones has to be relieved using percutaneous techniques. In this report we describe our approach in detail and discuss our results.     

Automated Intraoperative EMG Testing During Percutaneous Pedicle Screw Placement

BACKGROUND: EMG screw testing has been shown to be sensitive and reliable in open spinal instrumentation cases. However, there is little evidence to show its applicability to percutaneous screw placement. PURPOSE: To demonstrate the utility of EMG testing in percutaneous techniques, where lack of direct visualization poses an added risk to nerve injury. STUDY DESIGN: Summary of intraoperative EMG results during percutaneous pedicle screw placement. METHODS: Percutaneous pedicle screws were placed in twenty patients (22 levels, 88 pedicles). The initial fluoroscopically-guided k-wires and the subsequent taps were insulated and stimulated via an automated EMG system. Low threshold values prompted repositioning of the pedicle trajectory. RESULTS: Four (5%) k-wires induced EMG thresholds less than 10mA, prompting repositioning. One was repositioned without improvement, but with improvement upon tapping. One k-wire with very low threshold (3mA) was repositioned with an improved result (13mA). In 78 pedicles (89%) the tap threshold was greater than the k-wire. CONCLUSIONS: EMG testing helps to identify suboptimal screw trajectories, allowing for early adjustment and confirmation of improved placement. Tapping often improved thresholds, perhaps by compressing the bone and creating a denser, more insulative pedicle wall. EMG testing may improve the safety of percutaneous screw techniques, where the pedicle cannot be visually inspected.     

Percutaneous instrumentation of the cervical and cervico-thoracic spine using pedicle screws: preliminary clinical results and analysis of accuracy

The pedicle screw instrumentation represents the most rigid construct of the cervical and cervicothoracic spine and in spite of the risks to neurovascular structures clinical relevant complications do not occur frequently. The steep angles of the cervical pedicles result in a wide surgical exposure with extensive muscular trauma. The objective of this study was the evaluation of the accuracy of cervical pedicle screw insertion through a minimally invasive technique to reduce access-related muscular trauma. Therefore, percutaneous transpedicular instrumentation of the cervical and cervicothoracic spine was performed in 15 patients using fluoroscopy. All instrumentations from C2 to Th4 were inserted bilaterally through 2 to 3-cm skin and fascia incisions even in multilevel procedures and the rods were placed by blunt insertion through the incision. Thin-cut CT scan was used postoperatively to analyze pedicle violations. 76.4% of 72 screws were placed accurately. Most pedicle perforations were seen laterally towards the vertebral artery. Critical breaches >2 mm or narrowing of the transversal foramen occurred in 12.5% of screws; however, no revision surgery for screw displacement was needed in the absence of clinical symptoms. No conversion from percutaneous to open surgery was necessary. It was concluded that percutaneous transpedicular instrumentation of the cervical spine is a surgically demanding technique and should be reserved for experienced spine surgeons. The indications are limited to instrumentation-only procedures or in combination with anterior treatment, but with the potential to minimize access-related morbidity.     

Robotic transanal access surgery

Transanal use of laparoscopic instrumentation has been described in several case reports as an alternative to transanal endoscopic microsurgery (TEM). Both of these techniques have significant technical limitations due to anatomical constrictions. Robotic technology with articulating instruments has been effectively used in many areas with anatomic limitations similar to the intraluminal use within the rectum. We present the technique of a full-thickness transanal resection of a rectal polyp with endorectal suturing using a robotic platform. Larger case series and trials are needed to compare outcome and cost with TEM. Alternative robotic platforms and instrumentation may be further developed for different and more advanced indications of transanal access surgery.     

History of Retractor Technologies for Percutaneous Pedicle Screw Fixation Systems

Minimally invasive techniques aimed at minimizing surgery‐associated risk and morbidity of spinal surgery have increased in popularity in recent years. Their potential advantages include reduced length of hospital stay, blood loss, and requirement for post‐operative analgesia and earlier return to work. One such minimally invasive technique is the use of percutaneous pedicle screw fixation, which is paramount for promoting rigid and stable constructs and fusion in the context of trauma, tumors, deformity and degenerative disease. Percutaneous pedicle screw insertion can be an intimidating prospect for surgeons who have only been trained in open techniques. One of the ongoing challenges of this percutaneous system is to provide the surgeon with adequate access to the pedicle entry anatomy and adequate tactile or visual feedback concerning the position and anatomy of the rod and set‐screw construct. This review article discusses the history and evolution of percutaneous pedicle screw retractor technologies and outlines the advances over the last decade in the rapidly expanding field of minimal access surgery for posterior pedicle screw based spinal stabilization. As indications for percutaneous pedicle screw techniques expand, the nuances of the minimally invasive surgery techniques and associated technologies will also multiply. It is important that experienced surgeons have access to tools that can improve access with a greater degree of ease, simplicity and safety. We here discuss the technical challenges of percutaneous pedicle screw retractor technologies and a variety of systems with a focus on the pros and cons of various retractor systems.     

Percutaneous hepatolithotomy: the Northwestern University experience

Obstruction of intrahepatic ducts by calculi can lead to abdominal pain, cholestasis, abscesses, and cholangitis. Patients with stones recalcitrant to extraction using endoscopic retrograde cholangiopancreatography (ERCP) have traditionally been referred to a general surgeon for open stone extraction or hepatic lobectomy despite its great potential morbidity. Borrowing techniques, instrumentation, and experience in performing percutaneous nephrolithotomy, we describe our experience with percutaneous hepatolithotomy (PHL), a minimally invasive, safe, and effective alternative to open surgery for recalcitrant biliary stones.     

Open lumbar disc operation. Technique and results

Various operative techniques are available for the treatment of lumbar disc herniation. The conventional lumbar discotomy is currently considered to be the standard procedure. Several large statistical studies have shown that the results in the majority of cases are very good and the complication rate is low if it is carried out correctly. A particular advantage of this technique is that almost all indications can be handled with a procedure that can be extended if necessary. Despite the availability of newer refined techniques (microdiscectomy or percutaneous procedures), the open lumbar discotomy still has an outstanding role in the management of lumbar disc herniation. Failure results more frequently from false indications or inadequate preoperative planning and less from technical variations.