[Are There Correlations Between Disc Degeneration and the Appearance of Lumbar Disc Herniations?]

Background: The correlation between disc prolapse and disc degeneration is important in the evaluation of clinical and occupational disease. The present clinical radiological study investigated whether there is a correlation between disc degeneration (chondrosis) and disc prolapses. Patients and Methods: The present study is a retrospectively trial which was performed with conservatively and surgically treated patients from 2011 till 2013 in our clinic. 100 patients with disc prolapse and chondrosis in current MRI images were recruited. We classified patients into those who exhibited a prolapse and chondrosis in the same segment, those with only disc prolapse and those with only chondrosis. Statistical evaluation for the correlation between chondrosis and disc prolapse was performed with the chi-square test. Odds ratios for prolapse and chondrosis were calculated, as well as interobserver reliability (kappa-value) between the first and second observers of radiological images. Results: In all segments in our 100 patients, 119 radiological findings were made (= 100 %). 54 findings (45 %) with disc prolapse in combination with chondrosis were identified in the same lumbar segment. 43 findings (36 %) exhibited disc prolapse without chondrosis and 22 (19 %) chondrosis without prolapse. In most cases, the findings were seen in the last two segments. There was a statistical correlation between disc prolapse and chondrosis, as seen with the chi-squared test. As regards odds ratios, disc prolapse with chondrosis was 1.25-fold more frequent than prolapse without chondrosis; chondrosis with prolapse was 2.37-fold more frequent than chondrosis without prolapse. The interobserver reliability showed a kappa-value of 0.79 with disc prolapses and a kappa-value of 0.85 with chondrosis. Conclusion: For patients with disc prolapse and chondrosis in the same segment, chondrosis was mostly seen in combination with a prolapse. A causal relation was found between prolapse and chondrosis in the same segment. The interobserver reliability showed high correlation for radiological findings with disc prolapse and very high correlations with chondrosis.

[Influence of disc degeneration on the development of disc prolapse]

PURPOSE

The present clinical-radiological study examines retrospectively the relation between lumbar disc prolapse and degenerations like chondrosis and spondylosis.

METHOD

Firstly the relation between disc prolapse and chondrosis was examined. 44 patients with disc prolapse and chondrosis in actual MRI scans in the same segment were recruited in our clinic. By regarding older MRI scans, we could find out which finding was first to occur. Concerning the second question, we followed patients with spondylosis to see if they could progress to a disc prolapse.

RESULTS

In 67% of our cases with disc prolapse and chondrosis, a chondrosis was seen before the disc prolapse. More than a half had had a spondylosis and a chondrosis in the same segment before the herniation. Only 33% of our cases showed a prolapse before chondrosis.

CONCLUSION

Concerning patients with disc prolapse and chondrosis in the same segment, chondrosis was seen before the herniation in most cases. Also patients with spondylosis progress to a herniation. A causal relation between both radiological findings is not possible. In a future study it must be analysed with statistical tests whether these results are generally valid.

Electric efficiency of the erector spinae in high performance amateur tennis players

AIM

The aim of the paper was to evaluate neuromuscular activity patterns of the lumbar erector spinae during isometric voluntary maximum trunk extension and how this could be influenced through a back exercise home program in high performance amateur tennis players.

METHODS

Experimental longitudinal study of the lower back in a clinical setting. Seventy high performance amateur tennis players underwent isometric trunk extension tests in a specially built apparatus with simultaneous surface electromyography (EMG) recording from right and left lumbar erector spinae. Imbalance quotients were calculated using Electric Efficiency measures. Isometric and electromyographic changes were reviewed after a 7-week daily home program of back exercise.

RESULTS

Neuromuscular imbalance of the lumbar erector spinae associated with reduced Electric Efficiency, closely related to handedness was observed amongst tennis athletes at the start of the study. After a 7-week back exercise home program, lumbar neuromuscular imbalances were evened out and the Electric Efficiency of the erector spinae improved significantly at lumbar level L2 and L4. No significant difference was measured in maximal isometric trunk extension strength.

CONCLUSION

The asymmetric trunk loading caused by tennis specific biomechanics with trunk hyperextension motions and trunk rotation seems to induce imbalanced muscle activity patterns of the lumbar erector spinae. A home program of back exercises for tennis players can help to compensate for these imbalances, improves Electric Efficiency patterns of the erector spinae and should therefore be integrated in the daily training routine of high performance tennis players.

[Minimally invasive injection therapy in lumbar syndromes]

Minimally invasive injection therapy is an effective approach for the treatment of sciatica with less complications. This therapy is a sufficient option in cases without absolute indications for operation.The paper describes in detail the different injection techniques like spinal nerve analgesia, epidural dorsal/perineural injections, vertebral joint infiltrations, and radiculographies.

[Radiological diagnosis of lumbar prolaps with quantitative and morphological criteria]

PURPOSE

The present study examines the differences of radiological diagnosis of lumbar prolaps with quantitative and morphological criteria. Advantages and disadvantages of both methods were analysed.

METHOD

Concerning the "Deutsche Wirbelsäulenstudie" (DWS) 286 male and 278 female patients between 25 and 70 years of age undergoing clinical or ambulant therapy for radicular symptoms and the diagnosis of a lumbar prolaps in CT and/or MRT were integrated into our study. Actual MRT and CT pictures of the patients' lumbar spine were analysed by an independent radiologist (primary radiologist). Radiological diagnosis was concerned with quantitative and morphological criteria. Radiological images of 100 selected patients were reexamined by another radiologist (secondary radiologist). On the basis of these results, the interobserver reliability (kappa) was calculated.

RESULTS

In 95.2% of all segments a prolaps was seen with quantitative and morphological criteria, in 4.5% a prolaps was analysed with quantitative and in 0.3% a prolaps was seen with morphological criteria. The radiological diagnosis of prolaps by quantitative criteria was confirmed by the operative findings. Many prolapses with lateral localisation were seen in these cases. Therefore radiological diagnosis on the basis of morphological criteria could be difficult. For both radiological methods similar interobserver reliabilities were calculated. To sum up both radiological methods are even equivalent. It is also possible to graduate the diagnosis with quantitative criteria. Detrimental effects of quantitative criteria could be difficulties in measurement with non-digital images.

CONCLUSION

Besides several recommendations in the international literature on the radiological analysis of prolaps with morphological criteria, diagnosis with quantitative criteria is also an effective method.

[Minimally invasive injection therapy for patients with radicular lumbar spine syndrome. First results of an minimally invasive treatment for patients with lumbar radiculopathy]

BACKGROUND

There are few studies on minimally invasive injection therapy (MIT) combined with multimodal conservative therapeutic options. Here, we evaluate the results of MIT in a clinical study.

METHODS

A total of 61 patients with radicular lumbar symptoms treated with MIT were examined before and 14.5 months after treatment. Subjective, objective, clinical and anamnestic parameters were considered.

RESULTS

In most cases, protrusions and prolapses were seen. Radicular pain, sensible and motoric deficits and also functionality of the spine could be rectified after MIT. No major complications were seen during treatment.

CONCLUSION

MIT is an effective approach with few complications for the treatment of patients with radicular syndromes.

Die konservative Therapie der aseptischen Femurkopfnekrose

Osteonecrosis of the femoral head is a locally destructive disease with a multifactorial genesis. The majority of patients are men between 35 and 45 years of age, who are increasingly reduced in their quality of life and career. As these patients are in the middle of their careers, osteonecrosis of the femoral head is even of increasing interest for the national economy. It is therefore of major interest to reduce the costs as well as the time for its therapy. Since conservative treatment is discussed controversially, it was the aim to focus on the current literature according to the criteria of evidence-based medicine and to prove the importance of conservative treatment of femoral head osteonecrosis.

[Neuromuscular imbalances of the lower back in tennis players--the effects of a back exercise program]

SUMMARY BACKGROUND DATA

Tennis players asymmetrically load the trunk while playing. Neuromuscular imbalances are risk factors for low back injuries. The association between neuromuscular activity patterns of the lower back and back exercise has not been researched yet.

METHODS

Simultaneous maximum isometric trunk extension test and surface-electromyographic recordings from lumbar erector spinae in 82 amateur tennis players in a specially built apparatus before and after a seven-week back exercise home program.

RESULTS

Left-right neuromuscular imbalances of lumbar erector spinae were present amongst 48 (58.5 %) out of 82 tennis athletes, statistically closely related to handedness. Within the training group (n = 70), neuromuscular imbalances of erector spinae were significantly evened out without a significant increase of maximum trunk extension strength. No such effects were detected within the control group (n = 12).

CONCLUSION

Tennis specific biomechanics seems to predispose to lumbar neuromuscular imbalances. A back exercise program for tennis player can significantly even out those imbalances.

[Minimal-invasive injection therapy for cervical syndromes]

The specific minimal-invasive injection therapy is a key-procedure for cervical spine syndromes when performing a multimodal pain-therapy. Due to the exactly placed injections pain can be overcome. Indication is given in cases of continuing spine pain and is an alternative to operative procedure, as for as no absolute indication for operation is given. The complex injection technique affords knowledge and expertise. The exact application and the specific complications are presented in detail.

Ausrissfestigkeit implantierter Pedikelschrauben in konventioneller und fluoroskopisch-navigierter Technik

AIM

Aim of the study was to compare pullout resistance of pedicle screws after conventional and fluoroscopic computer-assisted implantation in the cadaveric thoracic and lumbar spine.

METHODS

Pedicle screws were inserted in a total of 10 vertebrae of different human specimens: 10 screws were placed using conventional technique (group 1) and 10 screws were inserted with fluoroscopic computer-assisted system contralaterally (group 2). Then pedicle screws were evaluated for biomechanical axial pullout resistance.

RESULTS

Mean pullout force was 232 N (range 60-600 N) in group 1 and 353 N (range 112-625 N) in group 2. The difference was significant (p=0,0425).

CONCLUSION

Fluoroscopic navigated implantation of pedicle screws increases the pullout strength in thoracic and lumbar cadaveric spines as compared with conventional methods.

[Stability of pedicle screws in comparison to anterior vertebral body screws after kyphoplasty augmentation]

AIM

Aim of the study was to compare stability of pedicle screws and ventral implanted screws after insertion in soft or cured kyphoplasty cement.

METHODS

Pedicle screws were inserted in a total of 40 thoracolumbar vertebrae of 10 different formalin-fixed human specimens: each 10 pedicle screws were implanted in soft (group 1) and cured cement (group 2), each 10 ventral screws were placed in soft (group 3) and cured (group 4) cement. Pedicle screws were then evaluated for biomechanical axial pullout resistance.

RESULTS

Mean pull-out force was 452 N (range 60-1 125 N) in group 1, 367 N (range 112-840 N) in group 2, 364 N (range 65-875 N) in group 3 and 271 N (range 35-625 N) in group 4.

CONCLUSION

Implantation of pedicle screws and ventral implanted screws in soft and cured kyphoplasty cement is a sufficient method. We achieved more stability with pedicle screws compared with ventral implanted screws in soft and cured cement. No significant difference was seen.

Long-term results of ventro-dorsal versus ventral instrumentation fusion in the treatment of spondylitis

This study examines prospectively the randomised, long-term, clinical and radiological results of the treatment of spondylitis patients by ventro-dorsal or ventral spine fusion. Group 1 consisted of 12 patients who (after ventral removal of the focus of infection and autologous bone grafting) were treated by dorsal instrumentation. Group 2 consisted of ten patients who, after similar ventral removal and bone interposition, were stabilised by ventral instrumentation. The patients prospectively underwent clinical and radiological studies. In addition, they were asked to fill in self-assessment questionnaires such as the short-form (SF)-36 health survey, the Oswestry questionnaire, and the visual analog scales (VAS). The postoperative follow-ups were at 6 months, 2 years and 5.4 years. It proved possible to demonstrate clinically that patients with an isolated ventral spondylodesis feel significantly better and experience significantly less pain in the area of spinal fusion than patients with ventro-dorsal fusion 2 and 5.4 years after the operation. Over a number of years a stable fusion can be achieved through either operation. Ventral stabilisation yields more advantages than dorsal instrumentation in the long term. These advantages result in a clinically smoother course after the operation. If, in the individual case, ventral instrumentation is feasible, this method should be used.

Stability of anterior vertebral body screws after kyphoplasty augmentation. An experimental study to compare anterior vertebral body screw fixation in soft and cured kyphoplasty cement

The goal of this cadaver study was to compare the stability of anterior vertebral body screws after implantation in soft or cured kyphoplasty cement. Anterior vertebral body screws were inserted in a total of 30 thoracolumbar vertebrae of ten different human specimens: ten screws were implanted in non-augmented vertebrae (group 1), ten screws were placed in soft cement (group 2), and ten screws were placed in cured cement (group 3). The screws were then tested for biomechanical axial pullout resistance. Mean axial pullout strength was 192 N (range: 10-430 N) in group 1, 364 N (range: 65-875 N) in group 2, and 271 N (range: 35-625 N) in group 3. The paired Student's t-test demonstrated a significant difference between pullout strength of groups 1 and 2 (p= 0.0475). No significant difference was seen between pullout strength of groups 1 and 3 (p= 0.2646) and between groups 2 and 3 (p= 0.3863). We achieved a 1.9 times higher pullout strength with kyphoplasty augmentation of osteoporotic vertebrae compared with the pullout strength of non-augmented vertebrae. Implantation of anterior vertebral body screws in cured cement is a satisfactory method. With this method we found a 1.4 times higher pullout strength than non-augmented vertebrae.

Micromotion in cemented rotating platform total knee arthroplasty: cemented tibial stem versus hybrid fixation

INTRODUCTION

Improving the longevity and reliability of cemented total knee arthroplasty (TKA) remains a major step to achieve. It is still unclear, whether a cemented tibial stem reduces micromotion of the tibial tray and produces therefore a better initial stability or not. The higher conformity of rotating platform design and the possible rotary forces to the tibial platform may produce higher micromotion when the tibial stem remains cementless (hybrid fixation).

MATERIALS AND METHODS

An in vitro study was performed using the PFC mobile bearing tibial tray (DePuy, Warswa, IN, USA) to test the hypothesis that the addition of cement surrounding the tibial stem reduces micromotion of the tibial tray in cemented TKA with mobile bearing design. Ten tibial trays with mobile design were implanted in sawbones with a 3-mm cement mantle beneath the baseplate of the tibial tray and with or without the cemented stem. Tibial trays were loaded additionally in the ventral, lateral, medial and posterior positions with 2,500 N using the Zwick Z010 instrumentation and HBM pick up Hottinger Baldwin.

RESULTS

In this study, a significant increased mean maximum liftoff was found when only cementing the tibial baseplate (hybrid fixation), compared to the fully cemented tibial tray (P<0.02).

CONCLUSION

In conclusion, the stem of mobile bearing tibial components should be cemented to provide increased micromotion and earlier loosening.

Implantatentfernung bei ventro-dorsalen Spondylodesen - Ist eine Entfernung des dorsalen Implantats nach knöcherner Durchbauung sinnvoll?

BACKGROUND

The present study on spondylitis patients with anterio-posterior spondylodesis was carried out to get a recommendation whether material removal is necessary after osseous fusion.

METHODS

A total of 12 patients with spondylitis were operated on at the Orthopaedic Department of Ludwig-Maximilians-University Munich with posterior instrumentation after debridement and fusion with autologous bone transplant. In a prospective clinical investigation we examined our patients regarding clinical and radiological outcome preoperatively, 2 weeks, 12 months and 4.9 years after operation. We paid special attention on complications and loss of correction in leaving posterior instrumentation.

RESULTS

Compared with the advanced clinical signs of spondylitis, minor intra- and postoperative complications were seen. Two patients showed superficial wound infections with fistulization because of the posterior implants 3 years postoperatively. Both cases closed after revision and material removal without complications. 12 months and 4.9 years postoperatively the average loss of correction was constant 2 degrees .

CONCLUSION

Generally material removal of posterior spinal instruments results in a significant loss of correction in the spondylodesis segment. Our study shows, that persisting posterior instrumentation could prevent loss of correction. On the other hand we recommend material removal in case of spondylodesis after osseous fusion to prevent wound healing complications.

Extrakorporale Einzeldosis und Durchleuchtungszeit bei bildwandler-kontrollierter und fluoroskopisch navigierter Implantation von Pedikelschrauben

AIM

Goal of the current study was to compare radiation dose and fluoroscopy time of fluoroscopic computer assisted pedicle screw implantation versus the conventional technique.

METHOD

For each of 10 specimens two pedicle screws were placed using conventional technique (group 1) and two screws were inserted with fluoroscopic navigation system (group 2) contralateraly.

RESULTS

For implantation of two pedicle screws the mean radiation dose was 0.041 mSv in group 1 and 0.029 mSv in group 2. Fluoroscopy time was 34 seconds in group 1 and 25 seconds in group 2. The differences of radiation dose and fluoroscopy time for group 1 and 2 were statistically significant (radiation dose p = 0.00044, fluoroscopy time p = 0.00039).

CONCLUSION

We achieved significantly lower radiation dose and fluoroscopy time with fluoroscopic computer assisted pedicle screw implantation compared with the conventional technique. Concerning exposure to radiation for patients and personnel fluoroscopic navigated screw insertion is to favour.

Vorgehensweise bei Sch�den der Gelenkmechanik beim Rotationsknieprothesen-Endo-Modell

In cases of mechanical damage of the Endo model rotating knee prosthesis, it is not necessary to change the complete prosthesis. Isolated replacement of the mechanics is possible. We changed a sled prosthesis of a 66-year-old patient to a rotating knee prosthesis because of ligament instability. After the patient fell and traumatized the operated knee, she experienced pain during weight bearing and instability. Because clinical and fluoroscopic examinations verified instability of the prosthesis, we decided to change the mechanics of the rotating knee prosthesis. In conclusion, mechanical damage of a rotating knee prosthesis is a rare complication. Operative treatment is easy to manage if replacement parts and instruments to change the mechanics have been organized preoperatively.

[Differences between anteroposterior and posterior spondylodesis in clinical scores]

The present study on spondylitis patients was carried out to compare prospectively results of clinical scores of patients treated with anteroposterior or anterior spondylodesis. A total of 22 patients with spondylitis were enrolled in the randomized trial to undergo an operation with anteroposterior or posterior spondylodesis. For quality of life adjustment, the SF-36 health survey was applied. Pain and disability were measured using the Oswestry low-back pain disability questionnaire and visual analogue scales (VAS). Twelve patients were assigned to undergo anteroposterior spondylodesis and ten patients anterior spondylodesis. Postoperative improvement of spinal function, general health, well being, back pain, and mobility could be observed in both groups of patients. Better results of patients treated with anterior spondylodesis compared with anteroposterior spondylodesis were seen. No statistical difference was found between the two groups at any time. The less invasive nature of anterior spondylodesis could be responsible for that result.Anterior spondylodesis should used if possible and deemed adequate because it causes less discomfort.

Erste Ergebnisse ventraler versus dorsaler Instrumentation nach Ausräumung und intervertebraler Fusion bei Spondylodiszitis

AIM

The present study on spondylodiscitis patients was carried out to compare prospectively and randomized the results of clinical and radiological outcomes of anterior versus posterior instrumentation after debridement and grafting. We aimed to make a recommendation concerning the optimum treatment of spondylodiscitis.

METHOD

A total of 22 patients with spondylodiscitis were enrolled in the randomized trial to undergo an operation with anterior or posterior instrumentation after debridement and fusion with autologous bone transplant. 12 patients (group 1) were assigned to posterior Universal Spine System stabilization. 10 patients (group 2) were treated with anterior VentroFix instrumentation. In a prospective clinical investigation we have examined both operative therapies with regard to clinical and radiological outcome. The follow-up was one year.

RESULTS

In patients with ventral Spondylodesis (group 2), prior recreation of patients was achieved in clinical examination and blood tests. Radiological results are even equivalent in both groups. Therefore we recommend ventral instrumentation as the superior surgical procedure. But the individual local situation has to enable ventral stabilization.

CONCLUSION

We found advantages with anterior instrumentation in comparison to posterior stabilization in patients with spondylodiscitis. Advantages of ventral stabilization cause early mobilization postoperatively without any increase in complication rates. Except for operation time and intraoperative blood loss, no statistical difference were was seen. Important is the individual indication for each method depending on anatomical and clinical signs. Ventral instrumentation should be restricted to cases with sufficient bone stock.