Clinical and radiological outcome at 10 years of follow-up after total cervical disc replacement.

PURPOSE: Previous studies have demonstrated that total cervical disc replacement (cTDR) represents a viable treatment alternative to the 'gold standard' anterior cervical discectomy and fusion for the treatment of well-defined cervical pathologies at short- and mid-term follow-up (FU). However, the implementation and acceptance of a non-fusion philosophy is closely associated with its avoidance of adjacent segment degeneration. Proof of the functional sustainability and clinical improvement of symptoms at long-term FU is still pending. The aim of this ongoing prospective study was to investigate the clinical and radiological results of cTDR at long-term FU. METHODS: 50 patients were treated surgically within a non-randomised prospective study framework with cTDR (ProDisc C™, Synthes, Paoli, PA, USA). Patients were examined preoperatively followed by routine clinical and radiological examinations at 1, 5 and 10 years after surgery, respectively. In addition to the clinical scores, conventional X-ray images of the cervical spine were taken in anteroposterior and lateral view as well as flexion/extension images. Clinical outcome scores included parameters such as the Neck Disability Index (NDI), Visual Analogue Scale (VAS), arm and neck pain self-assessment questionnaires as well as subjective patient satisfaction rates. The radiological outcome variables included the range of motion (ROM) of the implanted prosthesis between maximum flexion and extension images, the occurrence of heterotopic ossifications and radiographic signs of adjacent segment degenerative changes. The reoperation rate following cTDR was recorded as a secondary outcome variable. RESULTS: A significant and maintained clinical improvement of all clinical outcome scores was observed after a mean FU of 10.2 years (VASarm 6.3-2.1; VASneck 6.4-1.9; NDI 21-6; p < 0.05). An increase in the incidence and the extent of heterotopic ossifications was noted during the post-operative course with a significant influence on the function of the prosthesis, which, however, did not reveal any detrimental effect on the patients' clinical symptomatology. Prosthesis mobility declined from 9.0° preoperatively and 9.1° at 1 year FU to 7.7° and 7.6° at the five- and ten-year FU examinations, respectively. Radiological signs of adjacent segment degeneration were detected in 13/38 (35.7%), however, in only 3/38 (7.9%) patients this radiological changes were associated with clinical symptoms requiring conservative treatment. Intraoperative technical failure in two cases required interbody fusion with a cage (2/50). One patient (1/48, 2.1%) treated this motion device had revision surgery at the index level. CONCLUSION: Cervical total disc replacement with ProDisc C demonstrated a significant and maintained improvement of all clinical outcome parameters at a follow-up of ≥10 years. The present long-term data reveal that with an exceptionally low implant-related reoperation rate and low symptomatic adjacent segment degeneration rate, cTDR may be regarded as a safe and viable treatment option.

The Oblique Anterolateral Approach to the Lumbar Spine Provides Access to the Lumbar Spine With Few Early Complications.

BACKGROUND: During the last 20 years several less-invasive anterior approaches to the lumbar spine have become standard, including the extreme lateral transpsoas approach. Although it is associated with a lower risk of vascular injury compared with anterior midline approaches, neuromonitoring is considered mandatory to avoid neurologic complications. Interestingly, despite neuromonitoring, the reported risk of neurologic deficits with the extreme lateral transpsoas approach is greater than observed with other anterior approaches. An alternative lateral, oblique, psoas-sparing approach, recently named the oblique lumbar interbody fusion, uses the anatomic pathway between the abdominal vessels anteriorly and the lumbar plexus laterally to decrease the risk of neurologic and vascular injury; however, as yet, little on this new approach has been reported. QUESTIONS/PURPOSES: We asked: what proportion of patients experienced (1) perioperative complications (overall complications), (2) vascular complications, and (3) neurologic complications after less-invasive anterior lumbar interbody fusion through the oblique lumbar interbody approach at one high-volume center? METHODS: We performed a chart review of intra- and perioperative complications of all patients who had undergone minimally invasive anterior lumbar interbody fusion through a lateral psoas-sparing approach from L1 to L5 during a 12-year period (1998-2010). During the study period, the oblique, psoas-sparing approach was the preferred approach of the participating surgeons in this study, and it was performed in 812 patients, all of whom are studied here, and all of whom have complete data for assessment of the short-term (inpatient-only) complications that we studied. In general, we performed this approach whenever possible, although it generally was avoided when a patient previously had undergone an open retro- or transperitoneal abdominal procedure, or previous implantation of hernia mesh in the abdomen. During the study period, posterior fusion techniques were used in an additional 573 patients instead of the oblique lumbar interbody fusion when we needed to decompress the spinal canal beyond what is possible through the anterior approach. In case of spinal stenosis calling for fusion in combination with a high disc space, severe endplate irregularity, or severe biomechanical instability, we combined posterior decompression with oblique lumbar interbody fusion in 367 patients. Complications were evaluated by an independent observer who was not involved in the decision-making process, the operative procedure, nor the postoperative care by reviewing the inpatient records and operative notes. RESULTS: A total of 3.7% (30/812) of patients who underwent the oblique lumbar interbody fusion experienced a complication intraoperatively or during the hospital stay. During the early postoperative period there were two superficial (0.24%) and three deep (0.37%) wound infections and five superficial (0.62%) and six deep (0.86%) hematomas. There were no abdominal injuries or urologic injuries. The percentage of vascular complications was 0.37% (n = 3). The percentage of neurologic complications was 0.37% (n = 3). CONCLUSIONS: The risk of vascular complications after oblique lumbar interbody fusion seems to be lower compared with reported risk for anterior midline approaches, and the risk of neurologic complications after oblique lumbar interbody fusion seems to be lower than what has been reported with the extreme lateral transpsoas approach; however, we caution readers that head-to-head studies will need to be performed to confirm our very preliminary comparisons and results with the oblique psoas-sparing approach. Similarly, future studies will need to evaluate this approach in terms of later-presenting complications, such as infection and pseudarthrosis formation, which could not be assessed using this inpatient-only approach. Nevertheless, with the results of this study the oblique psoas-sparing approach can be described as a less-invasive alternative for anterior lumbar fusion surgery from L1 to L5 with a low risk of vascular and neurologic damage and without costly intraoperative neuromonitoring tools. LEVEL OF EVIDENCE: Level IV, therapeutic study.

Risk assessment of back pain in youth soccer players.

The purpose of this study is to identify several responsible parameters for back pain (BP) in youth soccer players to create a risk assessment tool for early prevention. An iPad-based survey was used to screen for parameters in a cross-sectional study. This questionnaire includes items regarding anthropometric data, training habits and sports injuries and was put into practice with 1110 athletes. Sex (odds ratio (OR): 1.84), age group (1.48) and playing surface (1.56) were significantly associated with BP. A history of injuries especially to the spine and hip/groin increased the likelihood for evolving recurrent BP (1.74/1.40). Overall 15 factors seem to influence the appearance of pain and were integrated into a feasible nomogram. The nomogram provides a practical tool to identify the risks of developing BP for youth soccer players. Although most factors we identified are non-modifiable, this method allows to rank the importance of factors and especially their prevention treatments for athletes.

Anterior stand-alone fusion revisited: a prospective clinical, X-ray and CT investigation.

PURPOSE: The purpose of this study was to assess the mid-term clinical and radiological results as well as patient safety in terms of complication and reoperation rates in patients treated with a novel anterior stand-alone fusion (ASAF) device (Synfix-LR, DePuy Synthes, West Chester, PA, USA) in a cohort of patients with predominant and intractable low back pain originating from monosegmental degenerative disc disease at the lumbosacral junction. METHODS: Clinical outcome scores visual analog scale (VAS), Oswestry disability index (ODI) and patient satisfaction rates were acquired within the framework of an ongoing single-center prospective clinical trial. Evaluation of radiological data included segmental and global lumbar lordosis, neuroforaminal height and width. Interbody fusion was assessed from post-operative CT scans. The minimum follow-up (FU) was 12 months. RESULTS: 71 out of an initial 77 patients were available for final FU (92.2 % FU rate) after a mean FU of 35.1 months (range 12.0-85.5 months). The overall results revealed a highly significant improvement from baseline VAS and ODI levels (p < 0.0001). 77.5 % (n = 55/71) of all patients reported a 'highly satisfactory' (n = 37/71; 52.1 %) or a 'satisfactory' (n = 18/71; 25.4 %) outcome; 22.5 % of patients were not satisfied. The overall complication rate was 12.7 % (n = 9/71). Two cases required post-operative revision surgery (2.8 %). Radiographical analysis demonstrated a highly significant increase of segmental lordosis from 16.1° to 26.7° (p < 0.0001). A high rate of solid interbody fusion was confirmed in 97.3 % of all cases (n = 36/37). CONCLUSION: The current study delineates satisfactory clinical results following ASAF at the lumbosacral junction. Patient safety was demonstrated with acceptable complication and low reoperation rates. Radiological data demonstrated a significant reconstruction of lordosis at the lumbosacral junction. Solid interbody fusion was achieved in 97.3 % of all cases in a highly selected cohort with optimal predisposition for fusion. ASAF may serve to avoid a variety of negative side effects for a considerable number of patients which, otherwise, would have been candidates for posterior instrumented fusion techniques.

A History of Endoscopic Lumbar Spine Surgery: What Have We Learnt?

The new development and finally the general acceptance of surgical techniques among the worldwide surgical community sometimes create fascinating stories. This is also true for the history of endoscopic lumbar spine surgery. In the last 100 years there was a "natural" evolution of surgical techniques with continuous improvement and "refinement" of lumbar decompression techniques towards less invasive operations with the final "endpoint" of microsurgery. However the application of percutaneous, image-guided, and endoscopic technologies has revolutionized minimally invasive surgery. This article describes the history of endoscopic lumbar spine surgery and its major milestones and protagonists which have helped to make endoscopic lumbar spine surgery "disruptive" minimally invasive surgical technology which has changed the world of lumbar decompression surgery. "The past is the mother of the future"Henri Cartier Bresson, French Photographer, 1908-2004.

[Unilateral approach for over the top bilateral lumbar decompression]. / Bilaterale mikrochirurgische Dekompression der lumbalen Spinalkanalstenose über einen unilateralen Zugang.

OBJECTIVE: The main goal is bilateral microsurgical decompression of the cauda equina using a unilateral over the top approach. The challenge is to achieve decompression with minimal iatrogenic trauma to anatomical structures in the approach region and in the target area. INDICATIONS: Degenerative spinal disorders including lumbar central stenosis, lumbar lateral recess spinal stenosis, and foraminal narrowing. This technique is performed in patients presenting primarily with neurogenic claudication, leg or buttock symptoms, heaviness in the legs with or without radicular symptoms, with or without neurological deficits, and comparable MRI findings. There are no limitations regarding number of affected segments or the extent of narrowing. CONTRAINDICATIONS: All available conservative treatment modalities not exhausted. Lack of serious neurological deficit. SURGICAL TECHNIQUE: Minimally invasive, muscle-sparing and facet-joint-sparing bilateral enlargement of the lumbar spinal canal through a unilateral microsurgical cross-over approach. POSTOPERATIVE MANAGEMENT: Patients are mobilized early 4-6 h postoperatively. Light sports activities (e.g., ergometer cycling, swimming) are allowed after 2 weeks. The same is true for the return to normal daily or work activities except for heavy physical work (usually 4 weeks out of work). Soft lumbar brace for 4 weeks (optional). RESULTS: The clinical outcomes are good to excellent. Meta-analyses and large case series report success rates for microsurgical decompression procedures of 73.5-95%. The reoperation rates are low (0.5-10%).

Analysis of post-operative pain patterns following total lumbar disc replacement: results from fluoroscopically guided spine infiltrations.

Although a variety of biomechanical laboratory investigations and radiological studies have highlighted the potential problems associated with total lumbar disc replacement (TDR), no previous study has performed a systematic clinical failure analysis. The aim of this study was to identify the post-operative pain sources, establish the incidence of post-operative pain patterns and investigate the effect on post-operative outcome with the help of fluoroscopically guided spine infiltrations in patients from an ongoing prospective study with ProDisc II. Patients who reported unsatisfactory results at any of the FU-examinations received fluoroscopically guided spine infiltrations as part of a semi-invasive diagnostic and conservative treatment program. Pain sources were identified in patients with reproducible (> or =2x) significant (50-75%) or highly significant (75-100%) pain relief. Results were correlated with outcome parameters visual analogue scale (VAS), Oswestry disability index (ODI) and the subjective patient satisfaction rate. From a total of 175 operated patients with a mean follow-up (FU) of 29.3 months (range 12.2-74.9 months), n = 342 infiltrations were performed in n = 58 patients (33.1%) overall. Facet joint pain, predominantly at the index level (86.4%), was identified in n = 22 patients (12.6%). The sacroiliac joint was a similarly frequent cause of post-operative pain (n = 21, 12.0%). Pain from both structures influenced all outcome parameters negatively (P < 0.05). Patients with an early onset of pain (< or =6 months) were 2-5x higher at risk of developing persisting complaints and unsatisfactory outcome at later FU-stages in comparison to the entire study cohort (P < 0.05). The level of TDR significantly influenced post-operative outcome. Best results were achieved for the TDRs above the lumbosacral junction at L4/5 (incidence of posterior joint pain 14.8%). Inferior outcome and a significantly higher incidence of posterior joint pain were observed for TDR at L5/S1 (21.6%) and bisegmental TDR at L4/5/S1 (33.3%), respectively. Lumbar facet and/or ISJ-pain are a frequent and currently underestimated source of post-operative pain and the most common reasons for unsatisfactory results following TDR. Further failure-analysis studies are required and adequate salvage treatment options need to be established with respect to the underlying pathology of post-operative pain. The question as to whether or not TDR will reduce the incidence of posterior joint pain, which has been previously attributed to lumbar fusion procedures, remains unanswered. Additional studies will have to investigate whether TDR compromises the index-segment in an attempt to avoid adjacent segment degeneration.

Development and Validation of the iDI: A Short Self-Rating Disability Instrument for Low Back Pain Disorders.

STUDY DESIGN: Cross-sectional and longitudinal validation study. OBJECTIVE: Development and validation of a short, reliable, and valid questionnaire for the assessment of low back pain-related disability. METHODS: The iDI was created in a stepwise procedure: (1) its development was based on the literature and theoretical consideration; (2) outcome data were collected and evaluated in a pilot study; (3) final validations were performed based on an international multicenter spine surgery outcome study including 514 patients; (4) the iDI was programmed for a tablet computer (iPad) and tested for its clinical practicability. RESULTS: The final version of the iDI comprises of 8 simple questions related to different aspects of disability with a 5-point Likert-type answer scale. The iDI compared very well to the Oswestry Disability Index in terms of reliability and validity. The iDI was demonstrated to be suitable for data assessment on a tablet computer (iPad). CONCLUSIONS: The iDI is a short, valid, and practicable tool that facilitates routine quality assessment in terms of low back pain-related disability.

"Slalom": Microsurgical Cross-Over Decompression for Multilevel Degenerative Lumbar Stenosis.

Objective. Selective, bilateral multisegmental microsurgical decompression of lumbar spinal canal stenosis through separate, alternating cross-over approaches. Indications. Two-segmental and multisegmental degenerative central and lateral lumbar spinal stenosis. Contraindications. None. Surgical Technique. Minimally invasive, muscle, and facet joint-sparing bilateral decompression of the lumbar spinal canal through 2 or more alternating microsurgical cross-over approaches from one side. Results. From December 2010 until December 2015 we operated on 202 patients with 2 or multisegmental stenosis (115 f; 87 m; average age 69.3 yrs, range 51-91 yrs). All patients were suffering from symptoms typical of a degenerative lumbar spinal stenosis. All patients complained about back pain; however the leg symptoms were dominant in all cases. Per decompressed segment, the average OR time was 36 min and the blood loss 45.7 cc. Patients were mobilized 6 hrs postop and hospitalization averaged 5.9 days. A total of 116/202 patients did not need submuscular drainage. 27/202 patients suffered from a complication (13.4%). Dural tears occurred in 3.5%, an epidural hematoma in 5.5%, a deep wound infection in 1.98%, and a temporary radiculopathy postop in 1.5%. Postop follow-up ranged from 12 to 24 months. There was a significant improvement of EQ 5 D, Oswestry Disability Index (ODI), VAS for Back and Leg Pain, and preoperative standing times and walking distances.

Microsurgical anterior approaches to the lumbar spine for interbody fusion and total disc replacement.

OBJECTIVE: Anterior approaches to the lumbar spine for the treatment of various degenerative or postoperative abnormalities associated with low back pain have always been a matter of debate. They are known to be associated with considerable surgical trauma, high postoperative morbidity, and, occasionally, unacceptably high complication rates. In 1997, we inaugurated two new microsurgical modifications of conventional anterior approach techniques, which have been applied in anterior lumbar interbody fusion and more recently in total disc replacement. This article describes the results of microsurgical anterior interbody fusion in a consecutive series of 171 patients as well as preliminary results of these techniques for total disc replacement in 26 patients. METHODS: The approaches are performed with the use of a surgical microscope. Lumbar segments L2-L5 are exposed through a lateral retroperitoneal approach. L5-S1 can be reached through a midline retroperitoneal or transperitoneal approach. Both approaches can be performed through a limited skin incision of 4 cm. RESULTS: An independent observer evaluated results of anterior lumbar interbody fusion in 171 patients during a 2-year follow-up period. The clinical follow-up demonstrated low perioperative and postoperative morbidity with an average blood loss of less than 100 ml at the fusion site. Pseudoarthrosis rates were less than 5%, and clinical results, as evaluated in accordance with the scoring system developed by Prolo et al., did not differ significantly from conventional open techniques. Total disc replacement through a microsurgical anterior approach seems to be a promising alternative to fusion procedures with even less intraoperative and perioperative morbidity. CONCLUSION: Microsurgical anterior approaches to the lumbar spine provide a reasonable surgical alternative to conventional approaches for anterior interbody fusion and total disc replacement.

Prosthetic total disk replacement--can we learn from total hip replacement?

Total lumbar disk replacement has become a routine procedure in many countries. However, discussions regarding its use are ongoing. Issues focus on patient selection, technical limitations, and avoidance or management of complications or long-term outcomes. A review of the development of this technology, since the development of the first successful implantation of a total lumbar disk prosthesis in 1984, shows an amazing analogy to the history of total hip replacement. This article is a one-to-one comparison of the evolution of total hip and total lumbar disk replacement from "skunk works" to scientific evidence.

Histological analysis of surgical lumbar intervertebral disc tissue provides evidence for an association between disc degeneration and increased body mass index.

BACKGROUND: Although histopathological grading systems for disc degeneration are frequently used in research, they are not yet integrated into daily care routine pathology of surgical samples. Therefore, data on histopathological changes in surgically excised disc material and their correlation to clinical parameters such as age, gender or body mass index (BMI) is limited to date. The current study was designed to correlate major physico-clinical parameters from a population of orthopaedic spine center patients (gender, age and BMI) with a quantitative histologic degeneration score (HDS). METHODS: Excised lumbar disc material from 854 patients (529 men/325 women/mean age 56 (15-96) yrs.) was graded based on a previously validated histologic degeneration score (HDS) in a cohort of surgical disc samples that had been obtained for the treatment of either disc herniation or discogenic back pain. Cases with obvious inflammation, tumor formation or congenital disc pathology were excluded. The degree of histological changes was correlated with sex, age and BMI. RESULTS: The HDS (0-15 points) showed significantly higher values in the nucleus pulposus (NP) than in the annulus fibrosus (AF) (Mean: NP 11.45/AF 7.87), with a significantly higher frequency of histomorphological alterations in men in comparison to women. Furthermore, the HDS revealed a positive significant correlation between the BMI and the extent of histological changes. No statistical age relation of the degenerative lesions was seen. CONCLUSIONS: This study demonstrated that histological disc alterations in surgical specimens can be graded in a reliable manner based on a quantitative histologic degeneration score (HDS). Increased BMI was identified as a positive risk factor for the development of symptomatic, clinically significant disc degeneration.

[The microsurgical anterior approach for total cervical disc replacement]. / Der mikrochirurgische anteriore Zugang zur Halswirbelsäule beim zervikalen Bandscheibenersatz.

OBJECTIVE: Mono- or bisegmental atraumatic microsurgical approach to the anterior cervical spine between C3 and C7 for total disc replacement. INDICATIONS: 'Soft' disc herniations C3-C7 with radicular symptoms. Ossified 'hard' disc herniations with preserved segmental motion. Erosive osteochondrosis with signs of activation (MRI: Modic I changes) and neck pain. Relative Indication: Adjacent segment degeneration following fusion. CONTRAINDICATIONS: Thyromegalie. Multiple previous cervical operations. Other implant-specific contraindications: Anterior osteophytes. Range of Motion (ROM) less than 5° (flexion/extension). Segmental collapse. Endplate anomalies (e.g. excessive concavity of cranial endplate). Endplate defects (e.g. Schmorl's nodes). Cervical myelopathy (limited postop evaluation of the spinal canal and spinal cord if implant is made out of ferromagentic materials). SURGICAL TECHNIQUE: Through a 2.5-3 cm skin incision, exposure and splitting of the platysma muscle. Blunt dissection between carotis sheath and esophageus/trachea with preservation of the thyroid blood vessels and the strap muscles (especially m. omohyoideus) and the recurrent laryngeal nerve. Exposure of the anterior disc space between the longus colli muscles after splitting of the prevertebral fascia. POSTOPERATIVE MANAGEMENT: Mobilisation the same day after 6-8 hrs. Functional postop treatment. Implant-dependent postop soft collar for max. 14 days. RESULTS: Safe and reliable anterior approach with low peri- and postoperative morbidity. In large series (> 900,000 operations) complication rate range between 2-2.9% [20]. Approach related complications are rare: postop Hematoma 0.39%, vascular Injuries (carotid artery, vertebral artery) (0.06%). Vocal cord palsy 0.14%, dysphagia 0.75%. Older age and cervical myelopathy have been identified as significant risk factors. Both situations don't play a significant role in total disc replacement since this type of operation is usually performed in young patients. Moreover, cervical myelopathy is still considered as a relative contraindication for total disc replacement.

[Percutaneous interspinous distraction for the treatment of dynamic lumbar spinal stenosis and low back pain]. / Die perkutane Implantation eines interspinösen Spacers an der Lendenwirbelsäule.

UNLABELLED: SURGICAL GOAL: Surgical treatment of dynamic lumbar spinal stenosis and discogenic/arthrogenic low back pain with a new percutaneous interspinous spacer as a therapeutic alternative to more invasive standard procedures. INDICATIONS: Central, lateral and foraminal dynamic lumbar spinal stenosis. Discogenic and arthrogenic (facet osteoarthritis) low back pain. Symptomatic, segmental hyperlordosis. Disc degeneration with dynamic (reducible) retrolisthesis. Interspinous pain ('Kissing-Spines'). CONTRAINDICATIONS: Osteoporosis. Conus-/Cauda-syndrome. Structural spinal stenosis. Spondylolisthesis (degenerative and/or isthmic). Deformities. Previous posterior operation in index segment. SURGICAL TECHNIQUE: Percutaneous, minimally invasive implantation of an interspinous spacer (InSpace ™, Synthes, Oberdorf, Switzerland). POSTOPERATIVE MANAGEMENT: Early unrestricted mobilization. RESULTS: Good early results (after 2 year follow-up) in 42 patients with 76% subjective patient satisfaction rate. No approach related complications. Avoidance of the more invasive alternative procedure (decompression, fusion, total disc replacement) in 76.2% of the patients.

[Minimally invasive anterior approaches to the lumbosacral junction]. / Minimalinvasive ventrale Zugänge zum lumbosakralen Übergang.

OBJECTIVE: Minimally invasive anterior preparation of the lumbosacral junction L5/S1 via a retro- or transperitoneal approach, possibility of intervertebral mono- or bisegmental rigid (cage, bone graft) or dynamic (disc arthroplasty) segmental stabilization. INDICATIONS: Degenerative disc disease (DDD) with or without disc herniation. DDD with translatoric or frontal instability. Degenerative or isthmic spondylolisthesis. Adjacent segment degeneration post fusionem. Failed back surgery syndrome (post discectomy, non-union). Spinal stenosis with dynamic segmental instability. Spondylitis/spondylodiscitis. CONTRAINDICATIONS: Previous transperitoneal lumbar fusion surgery. Adipositas permagna. Relative: Previous abdominal or gynaecological surgery. Aorta bifurcation and/or venous confluens directly in front of the lumbosacral disc space. Inflammation with large prevertebral granulation tissue formation or psoas abscess. Diseases of the gastrointestinal tract. SURGICAL TECHNIQUE: Anterior horizontal or vertical midline incision over L5/S1. Retroperitoneal or transperitoneal approach via the left or right lower abdomen. Retroperitoneal technique: medialization of the peritoneal sack towards the contralateral side. Transperitoneal technique: mini laparatomy, dissection of the visceral and parietal peritoneum and mobilization of the bowels laterally. Preparation of the anterolateral circumference of the L5/S1 disc space and mobilization of the vessels laterally. Discectomy and preparation of graft bed. POSTOPERATIVE MANAGEMENT: Functional postoperative care with mobilisation without external support following total lumbar disc replacement; stable trunk brace for 12 weeks in the case of fusion surgeries; no restrictions for standing, walking or sitting. RESULTS: Between January 2002 and December 2007, 454 patients (248 female, 206 male, average age 47.3 years, range between 15.4 years and 80.0 years,) underwent anterior surgery in the lumbosacral segment using a minimally invasive anterior approach. The spectrum of indications included monosegmental disc degeneration, spinal stenosis with segmental instability, isthmic oder degenerative spondylolisthesis, spondylodiscitis and others. Dynamic segmental support using total lumbar disc replacement was performed in 251 cases. Rigid stabilization with combined posterior internal fixation and anterior interbody fusion was performed in 203 cases (alternatively cage, tricortical iliac crest bone graft, bone substitutes such as hydroxyapatite or bone morphogenetic protein [BMP]). Approach-related, vascular complications occurred in 0.5 % (mainly left common iliac vein). Injuries of the gastrointestinal tract or urogenital tract (kidney, ureter, bladder) did not occur and there were no infections.

[Total cervical disk replacement--implant-specific approaches: keel implant (Prodisc-C intervertebral disk prosthesis)]. / Zervikaler Bandscheibenersatz--implantatspezifische Zugänge: Kielimplantat (Prodisc-C Bandscheibenprothese).

OBJECTIVE: Dynamic intervertebral support of the cervical spine via an anterolateral approach using a modular artificial disk prosthesis with end-plate fixation by central keel fixation. INDICATIONS: Cervical median or mediolateral disk herniations, symptomatic cervical disk disease (SCDD) with anterior osseous, ligamentous and/or discogenic narrowing of the spinal canal. CONTRAINDICATIONS: Cervical fractures, tumors, osteoporosis, arthrogenic neck pain, severe facet degeneration, increased segmental instability, ossification of posterior longitudinal ligament (OPLL), severe osteopenia, acute and chronic systemic, spinal or local infections, systemic and metabolic diseases, known implant allergy, pregnancy, severe adiposity (body mass index > 36 kg/m2), reduced patient compliance, alcohol abuse, drug abuse and dependency. SURGICAL TECHNIQUE: Exposure of the anterior cervical spine using the minimally invasive anterolateral approach. Intervertebral fixation of retainer screws. Intervertebral diskectomy. Segmental distraction with vertebral body retainer and vertebral distractor. Removal of end-plate cartilage. Microscopically assisted decompression of spinal canal. Insertion of trial implant to determine appropriate implant size, height and position. After biplanar image intensifier control, drilling for keel preparation using drill guide and drill bit, keel-cut cleaner to remove bone material from the keel cut, radiologic control of depth of the keel cut using the corresponding position gauge. Implantation of original implant under lateral image intensifier control. Removal of implant inserter. POSTOPERATIVE MANAGEMENT: Functional postoperative care and mobilization without external support, brace not used routinely, soft brace possible for 14 days due to postoperative pain syndromes. RESULTS: Implantation of 100 cervical Prodisc-C disk prostheses in 78 patients (average age 48 years) at a single center. Clinical and radiologic follow-up 24 months postoperatively. Significant improvement based on visual analog scale and Neck Disability Index. Radiologic improvement of segmental lordosis and mobility in the index segment. Incidence of spontaneous fusion in the index segments 8.75% without significant relation to the clinical outcome.