Transiliac Approach Research Articles

Safety and Preliminary Effectiveness of Lateral Transiliac Sacroiliac Joint Fusion by Interventional Pain Physicians: A Retrospective Analysis.

Minimally invasive sacroiliac (SI) joint fusion has become the mainstay treatment for chronic refractory sacroiliac joint dysfunction. Multiple procedures are now available including transfixing procedures with implants placed in the lateral or posterolateral transiliac trajectories, and intra-articular procedures with devices and/or allograft placed via a dorsal approach. To date, the published literature on the lateral approach has been primarily by surgeons. This retrospective chart review aims to evaluate the safety and preliminary effectiveness when the procedure is performed by physicians trained in interventional pain management. Retrospective analysis of patients who underwent lateral SI joint fusion using a lateral transiliac approach between December 2022 and September 2023 by a single physician. Data on demographics, perioperative details, complications, and postoperative outcomes were collected and analyzed. The study was reviewed by WCG IRB and received an exemption authorization. Medical charts were reviewed for the first 49 consecutive cases performed. Mean (SD, range) age was 64 (11, 34-83), BMI was 32.5 (8.4), 59% were female, 35% were smokers, and 82% were on opioids at baseline. Mean (SD) operative time was 40 (11) minutes and all procedures were performed at an ambulatory surgery center under monitored anesthesia care. No device- or procedure-related complications occurred. Mean follow up was 175 days; Mean (SD) baseline reported pain was 9 (1.5) on a 0-10 numerical rating scale. At follow up, 88% of the patients reported ≥50% pain relief. Six patients who reported 0% relief suffer from multiple pain generators and are on long term opioids. Results of this single center experience support the safety of lateral SI joint fusion using a threaded implant when performed by interventional pain management physicians. However, further prospective studies with larger sample sizes and longer follow-ups are warranted to validate these findings.

ILIF ASSISTIDA POR ENDOSCOPIA POR VIA TRANSILÍACA: ESTUDO EM CADÁVER

ABSTRACT Objective: Demonstrate the feasibility of endoscopic assisted L5S1 intraforaminal lumbar interbody fusion (iLIF) through a transiliac approach. Methods: Ten transiliac iLIF and ten supra iliac iLIF were performed bilaterally at L5S1 in five randomly selected fresh-frozen human cadavers. The following measurements were recorded: distances from the transiliac track to the iliac crest, posterior superior iliac spine, and superior gluteal neurovascular bundle; pelvic parameters; approach angles; cage’s lateral and AP center point ratio (CPR); percentage of the cage crossing the midline in the AP and lateral views. Endplate integrity was assessed through endoscopic visualization. In addition, the facet joint, sacroiliac joint, iliolumbar ligament, and exiting and traversing nerve roots were checked for integrity through anatomic dissection. Results: In the transiliac technique, the axial and coronal approach angles were significantly decreased by 13.5º (95% CI -15.5; -11.5; p value<0.001) and 13.2º (95% CI -15.3; -11.1; p value<0.001), respectively, the sagittal approach angle was significantly increased by 5.4º (95% CI 1.8,8.9; p-value = 0.008), and the AP CPR was significantly higher (MD 0.16; 95% CI 0.12,0.20; p value<0.001). The percentage of the cage crossing the AP view’s midline was increased by 31.6% (95% CI 19.8,43.4; p value<0.001). The integrity of endplates, facet joints, sacroiliac joints, iliolumbar ligament, and exiting and traversing nerve roots was maintained. Conclusion: L5S1 transiliac iLIF is a feasible surgical technique. It allows a more centrally placed interbody cage in the coronal plane without compromising the anterior position in the lateral plane. The integrity of the major anatomic structures at risk was preserved. Evidence Level III: A case-control study.

2021 Canadian Spine Society Abstracts.

# Abstract 45. Determining clinically important improvement following surgery for degenerative conditions of the spine: analysis of the Canadian Spine Outcomes and Research Network (CSORN) Registry {#article-title-2} There is significant variability in clinically important improvement (CII)

Trends in Diagnosis and Treatment of Sacroiliac Joint Pathology Over the Past 10 Years: Review of Scientific Evidence for New Devices for Sacroiliac Joint Fusion

Sacroiliac (SI) joint pathology is a newly appreciated contributor to lower back pain. Sacroiliac joint fusion (SIJF) has grown rapidly in popularity in association with the advent of minimally-invasive surgical techniques. This has led to an explosion of new medical devices used for SIJF. The objective of this article is to outline clinical trends, summarize the current data, and categorize novel devices for SIJF. Trends in SI joint pathology and fusion were obtained via the Healthcare Cost and Utilization Project’s (HCUP) National Inpatient Sample (NIS) database and Web of Science. To review literature on devices for SIJF, PubMed was searched using the Boolean phrase “sacroiliac joint AND (fusion OR arthrodesis)” since 2010. To establish a list of SIJF devices not represented in the literature, searches were performed on the FDA 510(k), premarket approval, and de novo databases, as well as Google and LinkedIn. Literature review yielded 11 FDA-approved devices for minimally invasive SIJF. Database query yielded an additional 22 devices for a total of 33 devices. Twenty-one devices used the lateral transiliac approach, six posterior allograft approach, three posterolateral approach, and three combined the lateral transiliac and posterolateral approaches. The evidence for the lateral transiliac approach is the most robust. Many novel devices have been developed for minimally invasive SIJF over the past 10 years. Further randomized comparative trials are warranted to evaluate different surgical approaches and novel devices at this time.

Review of Current Evidence for Minimally Invasive Posterior Sacroiliac Joint Fusion.

The sacroiliac joint (SIJ) is a large, irregularly shaped, serpentine joint structure bordered anteriorly and posteriorly by the sacroiliac ligaments. With increased recognition of the SIJ as a pain source, treatments have been historically nonsurgical in nature. Common treatments include bracing, medications, activity modification, manual therapy, chiropractic manipulation, physical therapy, and intra-articular SIJ injections. Surgical stabilization and/or fusion of the SIJ may be considered when a patient has persistent moderate to severe pain, functional impairment, and failed conservative management. Surgical stabilization and fusion has traditionally been by way of the transiliac approach. More recent SIJ fusion systems have proposed not only a posterior approach but one that stabilizes the joint space by placing an allograft within the SIJ. Anatomically, a posterior approach is able to avoid neurovascular structures that otherwise are encountered with the transiliac approach and may be performed percutaneously. Preliminary evidence reports consistent pain reduction with minimal complications. This paper is purposed to detail the present evidence of minimally invasive posterior SIJ fusion, as well as highlight the need for further research moving forward.

Suprailiac versus transiliac approach in transforaminal endoscopic discectomy at L5-S1: a new surgical classification of L5-iliac crest relationship and guidelines for approach.

Approach to the L5-S1 level with transforaminal access can be challenging. Some surgeons employ the interlaminar or paraspinal endoscopic approach as an alternative apart from the other minimally invasive posterior surgical options. To precisely target and safely access disc herniations at L5-S1, the authors attempted to stratify patients into trans and supra iliac approach groups and propose a simple surgical classification based on the radiographic findings. A prospective study was performed on a cohort of 90 patients with L5-S1 disc herniation who underwent transforaminal endoscopic discectomy through suprailiac or transiliac approach depending on the best trajectory to access the herniated disc. Preoperative radiological assessment was done on anteroposterior and lateral radiographs of the lumbosacral spine by two independent observers. The proposed classification and approach guidelines were used to stratify patients for the preferred access route. The outcome was measured as mean VAS and ODI scores pre-operative and at 6 months post-operative and compared using the null hypothesis (P value) and the paired t-test. The interrater reliability was calculated as the percentage agreement between different observers. The L5-S1 disc herniation was treated with the transforaminal approach in 46 patients via the suprailiac and in the remaining 44 patients via the transiliac approach. There were statistically significant VAS and ODI reductions in patients of both groups (P<0.05). Interrater reliability of 92.5% using percent agreement shows strong level of agreement. This surgical approach classification based on radiographs aids in the preoperative planning for selection of patients to either suprailiac or transiliac approach for transforaminal endoscopic surgery at L5-S1 level.

Endoscopic transiliac approach to L5-S1 disc and foramen, technique and results

BACKGROUND: Transforaminal endoscopic discectomy has become popular due to its advantages over open discectomy. However, transforaminal endoscopic surgery may be difficult to perform at L5-S1 level in some cases due to anatomic variations such as high iliac crest. Endoscopic transiliac approach is an option for patients with high iliac crest or narrow foramen. The aim of this retrospective study was to describe the technique, analyse the results and complications. MATERIALS AND METHODS: 10 patients with variety of L5-S1 disc pathology who were treated with endoscopic transiliac surgery under local anaesthesia from June 2015 to December 2016 were included in the study. Clinical follow up was done at one month, three months, six months, one year. Outcome was assessed using modified Macnab's criteria. RESULTS: All patients had immediate relief from symptoms. Excellent outcome was noted in eight patients, Good outcome in one patient, and fair result in one patient. No patient had any complications. No patient required conversion to open or alternative procedure. Mean hospital stay was 1 day. CONCLUSIONS: Endoscopic transiliac approach is safe and effective in lumbosacral disc pathologies. Transiliac approach removes the limitations of transforaminal approach for L5-S1 disc space. Transiliac approach is the only versatile minimally invasive approach to lumbosacral junction which can tackle variety of clinical conditions.

Application of transiliac approach to intervertebral endoscopic discectomy in L5/S1 intervertebral disc herniation

ObjectiveTo discuss the significance and the short-term effect of bone puncture technique in transiliac approach to intervertebral endoscopic discectomy for the treatment of L5/S1 intervertebral disc herniation.MethodsNineteen patients were diagnosed as L5/S1 disc herniation and treated using transiliac approach to endoscopic discectomy (group I), and 20 patients were diagnosed as non-L5/S1 disc herniation and underwent conventional approach (group R). Leg pain was evaluated by VAS. MacNab ratings of the last follow-up were recorded to evaluate early clinical efficacy, and postoperative complications were recorded to evaluate surgical safety. The imaging changes of the patients 3 months after surgery were observed.ResultsOne patient in group I, who felt abnormal in nerve roots, underwent symptomatic treatments, such as rehydration and hormone, and the abnormalities disappeared 3 days after treatment. There were no significant significances in operative time and intraoperative fluoroscopy times between groups I and R (p > 0.05), but there was a higher tendency in group I. The VAS scores of post-operation were significantly lower than that of pre-operation in the two groups (p < 0.05), but there were no significant differences between the two groups (p > 0.05). The MacNab score of the last follow-up showed excellent rate (95%) and good rate (90%) in groups I and R, respectively.ConclusionsBone puncture-combined transiliac approach to intervertebral endoscopic surgery could locate iliac puncture point individually, and establish a good iliac channel, which is safe, effective, and minimally invasive.

Endoscopic trans-iliac approach to L5-S1 disc and foramen - a report on clinical experience.

BackgroundThe lumbosacral junction is a difficult area for spine surgery because of the complex anatomy. In the era of minimally invasive spine surgery, the presence of the iliac wing has, at the level of lumbosacral junction, created a major obstacle in the paths of two of the major approaches, namely, the direct lateral and percutaneous posterolateral endoscopic approaches. A trans-iliac cadaver study published by the senior author and co-workers in 1997, suggested the possibility of an alternative approach to the lumbosacral junction.PurposeTo determine the feasibility of percutaneous, endoscopic trans-iliac approach to the L5-S1 disc and foramenStudy DesignProspective case series study.Materials and Methods15 consecutive patients undergoing the transiliac approach to L5-S1 disc and foramen were included in the study. Pre- and postoperative visual analogue scale (VAS); Oswestry Disability Index (ODI); and intra-operative blood loss and operative time, were obtained for the study. Preoperative MRI or CT scan was used to determine the need for trans-iliac access. The procedure was performed with the patient in prone position and under monitored sedation for decompression. Endotracheal anesthesia was used for fusion cases. The transiliac access was established with a cannulated drill or core drill through the iliac wing. Once the trans-iliac window had been created, the rest of the procedure proceeded as for percutaneous endoscopic transforaminal decompression and fusion.Results15 patients (9 male and 6 female) participated in the study. The VAS for back and leg pain significantly improved in all patients. The ODI dropped by more than 50%. There was minimal blood loss, and transient post-operative dysesthesia in 2 cases which resolved after 3 weeks.ConclusionEndoscopic trans-iliac approach to the L5-S1 disc and foramen is feasible and safe. Decompression can be performed safely via trans-iliac access with minimal blood loss, and in a short operative time.

Treatment of Denis 1, 2 and 3 insufficiency fracture zones of the os sacrum

ZusammenfassungBeiälteren Patienten mit reduzierter Knochenqualität sind Insuffizienzfrakturen des Os sacrum relativ häufig und typischerweise mit starken, invalidisierenden Schmerzen verbunden. Ziel unserer Studie war die Durchführbarkeit der Zementaugmentation mittels Ballonkatheterüber individuelle, die komplexe Anatomie des Os sacrum und die Ausrichtung des Frakturgeschehens berücksichtigende Zugangswege sowie die postinterventionelle Erfassung von Leckagen und Darstellung des klinischen Outcomes. Bei 40 Patienten mit schwerer Osteoporose (24 Frauen mit einem Durchschnittsalter von 74,4 Jahren, 16 Männer mit einem Durchschnittsalter von 69,7 Jahren) wurde im CT und MRT eine Ossacrum-Fraktur detektiert. Bei 17 Frauen und neun Männern war diese Fraktur unilateral, bei sieben Frauen und sieben Männern bilateral. Die Frakturen wurden nach Denis eingeteilt. Um eine Zementverteilung in Längsrich-tung zur Fraktur zu erreichen, wurde der Ballonkatheterüber eine Hohlnadel in das Os sacrum entweder von dorsal nach ventral, von caudal nach cranial oder von lateral nach medial transiliacal eingebracht. Der Ballonkatheter wurde daraufhin entlang der Fraktur in der entsprechenden Richtung einbis dreimal in-und deflatiert. Der dadurch geschaffene Hohlraum wurde dann mit PMMA-Zement im Niederdruckverfahren aufgefüllt. Anschließend erfolgte eine konventionelle Röntgenaufnahme in zwei Ebenen sowie ein Kontroll-CT. Die Schmerzintensität wurde prä interventionem, am zweiten Tag sowie sechs und zwölf Monate post interventionem mittels visueller Analogskala (VAS) bestimmt. Zusätzlich wurde die Patientenzufriedenheit nach zwölf Monaten abgefragt. Bei allen Patienten ließ sich die Ballon-Sakroplastie technisch gut anwenden. In der Röntgen-und CT-Kontrolle fand sich im Os sacrum entlang der Frakturausdehnung eine ausreichende Zementverteilung, wobei eine Leckage ausgeschlossen werden konnte. Der Mittelwert für Schmerzen lag nach VAS vor Intervention bei 8,9, die Patienten mit einer Denis-2-Fraktur hatten tendenziell die stärksten Schmerzen. Am zweiten postoperativen Tag zeigte sich eine signifikante Schmerzreduktion (p &lt; 0,001) mit einem Durchschnittswert von 2,7; dieser war mit 2,5 nach sechs Monaten und mit 2,3 nach zwölf Monaten stabil. Nach zwölf Monaten fand sich eine hohe Patientenzufriedenheit. Zugangswege, welche die Anatomie des Os sacrum und die Frakturausrichtung im Os sacrum berücksichtigen, erlauben eine mengenoptimierte und sichere Zementaugmentation. Die Ballon-Sakroplastie wird hierdurch zu einer effektiven, komplikationsarmen Behandlungsmethode zur schnellen und signifikanten Schmerzreduktion bei Patienten mit einer Os-sacrum-Fraktur.

Trans-Iliac Rat Aorta Stenting: A Novel High Throughput Preclinical Stent Model for Restenosis and Thrombosis

Currently, preclinical stent development requires elaborate large animal models, which are time consuming and expensive. We herein report a high throughput rat aorta stenting model which could provide a rapid and low-cost platform for preclinical stent development. A total of 86 metal stents (316L stainless steel 13 mm, VasoTech, Inc.) coated with poly (D, L-lactide-co-glycolide)/amorphous calcium phosphate (PLGA/ACP) copolymer were pre-mounted on 1.5 mm× 15 mm balloon catheters and were implanted into aspirin treated Sprague-Dawley rats (500-700 g) initially using either direct placement in the abdominal aorta (group A, n = 7) or a trans-iliac approach (cut-down, group B, n = 79). The surviving rats were sacrificed at 1, 2, 4, and 12 wk post-implantation and the stented arteries were analyzed histopathologically. Four rats died in group A and nine rats died in group B within 48 h post-stent implantation (mortality: 57% versus 11%, P < 0.05). All animals that died had stent thrombosis/paralysis with visible thrombus on necropsy. Histologically, neointimal growth peaked at approximately 4 wk post-implantation. This result suggests that human-sized stents can be successfully implanted into the rat aorta via iliac artery insertion with a significantly higher survival rate than trans-aorta implantation. The model system allows rapid (4-12 wk) assessment of stent biocompatibility with mortality/paralysis used as an indicator of stent thrombosis.

Screw Placement and Osteoplasty Under Computed Tomographic–Fluoroscopic Guidance in a Case of Advanced Metastatic Destruction of the Iliosacral Joint

We present a case of combined surgical screw placement and osteoplasty guided by computed tomography-fluoroscopy (CTF) in a 68-year-old man with unilateral osteolytic destruction and a pathological fracture of the iliosacral joint due to a metastasis from renal cell carcinoma. The patient experienced intractable lower back pain that was refractory to analgesia. After transarterial particle and coil embolization of the tumor-feeding vessels in the angiography unit, the procedure was performed under general anesthesia by an interdisciplinary team of interventional radiologists and trauma surgeons. Under intermittent single-shot CTF, two K wires were inserted into the left iliosacral joint from a lateral transiliac approach at the S1 level followed by two self-tapping surgical screws. Continuous CTF was used for monitoring of the subsequent polymethylmethacrylate injection through two vertebroplasty cannulas for further stabilization of the screw threads within the osteolytic sacral ala. Both the screw placement and cement injection were successful, with no complications occurring during or after the procedure. With additional nonsteroidal anti-inflammatory and opioid medication, the patient reported a marked decrease in his lower back pain and was able to move independently again at the 3-month follow-up assessment. In our patient with intolerable back pain due to tumor destruction and consequent pathological fracture of the iliosacral joint, CTF-guided iliosacral screw placement combined with osteoplasty was successful with respect to joint stabilization and a reduction in the need for analgesic therapy.

Percutaneous Endoscopic Lumbar Discectomy by Transiliac Approach

Case report. The authors report a new percutaneous endoscopic lumbar discectomy (PELD) technique for the treatment of lumbar disc herniation with a high iliac crest via a transiliac approach. When the iliac crest is high, the L4-L5 and L5-S1 disc spaces are located deep in the pelvis, so they are not easily accessible via a suprailiac route. A 51-year-old man manifested left gluteal and leg pain due to an up-migrated soft disc herniation at the L4-L5 level. Transforaminal PELD via a transiliac approach was performed to remove the herniated fragment, achieving complete decompression of the nerve root. The symptom was relieved and the patient was discharged the next day. When a conventional transforaminal PELD is impossible due to the presence of a high iliac crest, PELD via a transiliac route could be a alternative option in selected cases.

Transiliac ICD implantation: Defibrillation vector flexibility produces consistent success

The transiliac approach to implantable cardioverter-defibrillator (ICD) implantation is an alternative in patients for whom pectoral placements are contraindicated. The defibrillation vector is altered from the pectoral configuration because of pulse generator placement in one of the upper abdominal quadrants and separate single-coil, active-fixation defibrillation leads positioned in the high right atrium and right ventricular apex. The feasibility, safety, and complications of this approach and the results of defibrillation testing (DFT) with this configuration are described. Twenty-three patients (16 male and 7 female, mean age 65.7 +/- 13.2 years) required transiliac approach to ICD placement. The leads were inserted through the iliac vein immediately superior to the inguinal ligament. When required, a subcutaneous coil was tunneled posterior to the left ventricle from the left axilla. The right iliac vein entry was used in 17 patients, with placement of the pulse generator in the left upper quadrant in 16 patients. Atrial and ventricular lead pacing and sensing function were acceptable. Initial defibrillation success with a safety margin of 10 J was achieved in 15 patients. With the placement of an additional subcutaneous coil in the remaining 8 patients, defibrillation success with a safety margin of 10 J was increased to 19 patients, whereas defibrillation success with a safety margin of 5 J was achieved in all patients, although 1 patient required repeat testing 24 hours after implantation. There were no acute complications. Late complications occurred in 3 patients, comprised of atrial lead malfunction, device infection, and right ventricular defibrillation lead fracture. The iliac vein approach to ICD implantation is a safe and effective alternative technique. Flexibility in lead placement, defibrillation vectors, and careful DFT are required to produce a consistently effective system.

Transiliac Approach for Exposure of Lumbosacral Intervertebral Disk and Foramen: Technique Description

To describe and evaluate a transiliac approach to the L7-S1 disk and intervertebral foramen in dogs. Cadaver study. Fresh canine cadavers (n=10). A craniolateral approach was made to each iliac wing of 10 fresh canine mixed breed cadavers. An 18 mm hole was drilled in a standardized position through the iliac wing. The musculature connected to the cranial aspects of the sacral wing was dissected and retracted cranially through this iliac window. Endoscopic exploration of the area was performed. The foramen and intervertebral disk were clearly observed in all specimens without iatrogenic injury of the L7 nerve branch. Access to the foramen was possible in 16 of 20 specimens without excision of the sacral wing; however, it was always partially excised to observe the intervertebral disk which lies more caudally and ventrally. Transiliac approach to the lumbosacral joint allows direct exposure of the intervertebral disk and foramen through an iliac window. Endoscopic exploration provided good observation of the intervertebral disk and/or foramen. Transiliac approach could be used for lateral corpectomy and foraminotomy in dogs with degenerative lumbosacral stenosis caused by ventral or ventrolateral disk protrusion, foramen stenosis, or OCD of the L7-S1 joint. Clinical study will be necessary to evaluate the efficacy of this approach.

Diagnosis, assessment, and treatment of bone turnover abnormalities in renal osteodystrophy

HE ABNORMALITIES of the skeleton in chronic kidney disease (CKD), collectively known as renal osteodystrophy, are an important cause of morbidity and decreased quality of life. In the management of patients with kidney disease, it is necessary to have a rational approach to the diagnosis and assessment of renal osteodystrophy in order to devise a treatment plan that hopefully will lead to an improved outcome. In the past, the term renal osteodystrophy was mainly equated only with abnormalities of bone turnover, but as described in the article by Cunningham and Sprague 1 in this same issue, renal osteodystrophy is a complex disorder of compromised bone strength in CKD patients. While osteoporosis is a term used to describe fragile bones prone to fracture in the general population and is most often assessed by dual x-ray absorptiometry (DEXA), renal osteodystrophy should be the principal term to describe fragile bones prone to fracture and other morbidities in CKD. Renal osteodystrophy is a function of bone turnover (assessed by bone biopsy), bone density (assessed by DEXA or quantitative CT [qCT]), and bone architecture, but the principal determinant of bone fragility in CKD is abnormal bone turnover. However, diagnosing and treating bone turnover abnormalities remains challenging. Our discussion group met to assess the current state of knowledge, understand the basis of our current therapy, and identify the information that needs to be gathered to improve the therapy of bone turnover and thereby improve the disorder of renal osteodystrophy. A number of important questions, listed in Table 1, were considered.

Computer-assisted percutaneous transiliac approach to tumorous malformation of the sacrum.

The object of this article is to present a new, minimally invasive, percutaneous image-guided technique for surgery of tumorous malformation of the sacrum. Using one of the available CAS systems, we developed a navigable working tube through which various surgical tools may be very precisely introduced into the tumorous malformation. The tube allows us to obtain histological samples and also perform tumor resections. For sacral procedures, the working tube was introduced percutaneously into the affected area of the sacrum through the sacroiliac joint with computer assistance. For successful matching, small titanium screws were inserted into the sacrum and pelvis percutaneously before CT examination to give precise landmark points. We have used the method in 12 cases. The aim of the surgery in biopsy cases was to obtain samples for histological diagnoses of unknown tumors. In the cases of tumor resection (all were metastatic), the indication was to obtain neurological decompression and decreased local pain. The pain response was very effective in all cases. The transiliac percutaneous approach to the sacrum has proven to be a safe and well-designed procedure. It can even be performed under local anesthesia, and is thus a very effective minimally invasive tool for obtaining pain relief in cases of sacral metastasis involving the first, second, and third segments.

The inferiorly based rectus abdominis myocutaneous flap for recurrent pelvic pressure sores in neurologically impaired patients

The inferiorly based rectus abdominis myocutaneous flap, developed by Taylor, is a reliable flap which when raised spares the anterior sheath of the muscle below the arcuate line. The muscle can fill an infected, hypovascular wound and the extensive skin paddle can cover a large cutaneous loss of substance, so the flap is perfectly suited to coverage of recurrent pressure sores in paraplegic patients. We used 11 flaps in 10 paraplegic patients for recurrent pelvic pressure sores which were ischial in six cases, trochanteric in four and sacral in one. We describe the operative technique and stress the importance of using an extraperitoneal, intrapelvic and transiliac approach. Healing was obtained in all cases without functional deficit of the abdominal wall (no abdominal herniation, one contour deformity). This flap offers two further options for treatment of recurrent pelvic pressure sores whatever their location and its indications are more and more frequent in an aging population of paraplegic patients.

Endoscopic transiliac approach to L5-S1 disc and foramen. A cadaver study.

The toros of fresh cadavers were used to create endoscopic channels through the iliac wings to gain access to the L5-S1 disc and foramen. The spine and pelvis then were dissected out en bloc, and the anatomic relationships were studied. To determine the feasibility of a transiliac approach to the L5-S1 disc and foramen and to assess the safety of this approach by studying the anatomic relationships of the transiliac track. Because of its location deep in the pelvis, the L5-S1 disc and foramen are not easily accessible via a supra-iliac portal. A laparoscopic approach violates the abdominal cavity, and makes major vessels and viscera at risk for injury. A core drill was inserted over a guide wire into the iliac wing under fluoroscopy to obtain a core of bone, which then was removed to create a transiliac channel. An arthroscope was inserted through the channel to perform discoscopy or foraminoscopy. The spine was dissected out en bloc to study the relationships of the track. It was possible to use a transiliac approach to L5-S1 in all the experiments. There was no damage of neural structures in any of the experiments. The results of this study suggest that it is possible to access the L5-S1 disc and foramen through the ilium without injuring important structures. It would be necessary to conduct a study based on an animal model and to evaluate the results before using this procedure in a clinical situation.

Anatomic considerations for posterior approach to the sacroiliac joint.

This anatomic study describes a new intraosseous, posterior approach to the sacroiliac joint. To define a transosseous approach to the sacroiliac joint in which a triangular bony window is raised on the posterosuperior aspect of the ilium that provides improved access to the sacroiliac joint for posterior fusion. A posterior approach to the sacroiliac joint has been widely used for debridement of infectious diseases and for fusion. Most conventional approaches to the sacroiliac joint are interosseous, and there is a relative lack of information on transiliac approaches. The projection of the sacroiliac joint on the outer table of the ilium and the thickness of the posterior ilium forming part of the sacroiliac joint were determined in 15 cadaveric pelves. A right angle, triangular bony window was raised from the posterior ilium to investigate the suitability of a transiliac approach in performing sacroiliac debridement and arthrodesis. A horizontal reference line 3-3.5 cm in length was drawn between a point 1 cm anterosuperior to the posteroinferior iliac spine and a point 1.5 cm superior to the superior border of the greater sciatic notch. A vertical reference line was extended superiorly for 2-2.5 cm perpendicular to and beginning at the anterior end of the horizontal reference line. The oblique arm of the right triangle was created by joining the superior end of the vertical reference line to the posterior end of the horizontal line. Thirty percent to fifty percent of the articular surface of the iliac bone was removed with this triangular segment of bone, and a corresponding area of the sacral articular surface was visualized directly. It was possible to remove the rest of the articular cartilage with angled curettes in all specimens. This approach facilities improved access to the sacroiliac joint for debridement and arthrodesis with minimal soft tissue dissection and iliac bone resection.