Posterior lumbar interbody fusion (PLIF) with cages and local bone graft in the treatment of spinal stenosis.

Posterior lumbar interbody fusion (PLIF) implants are increasingly being used for 360 degrees fusion after decompression of lumbar spinal stenosis combined with degenerative instability. Both titanium and PEEK (PolyEtherEtherKetone) implants are commonly used. Assessing the clinical and radiological results as well as typical complications, such as migration of the cages, is important.

Epidural neuroplasty versus physiotherapy to relieve pain in patients with sciatica: a prospective randomized blinded clinical trial.

Background: Epidural neuroplasty seems to be one of the promising minimally invasive techniques for adhesiolysis in patients with chronic sciatica with or without low back pain. However, because no data exist from randomized studies the aim was to investigate whether this procedure is superior to conservative treatment with physiotherapy.

Methods: A total of 99 patients with chronic low back pain were enrolled in this study and randomly assigned into either a group with physiotherapy (n = 52) or a second group undergoing epidural neuroplasty (n = 47).

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.

[Macerated human hip bone preparation as a substitute for fresh frozen preparations for testing the primary stability and frictional torques of cementless hip cups].

Aim: The aim of the study was to validate macerated human acetabuli as replacement for fresh frozen preparations for testing primary stability and the screwing in moments of cementless threaded hip cups.

Method: Three fresh frozen human pelvis were tested. One half of each pelvis was macerated whereas the other half was preserved as fresh frozen preparation.

A prospective morphological study of facet joint integrity following intervertebral disc replacement with the CHARITE Artificial Disc.

In degenerative disc disease (DDD), increased loading in the posterior column increases facet joint subchondral bone density and may lead to facet joint degeneration. While spinal fusion is commonly used to treat patients with symptomatic DDD, increased stress at the levels adjacent to fusion may accelerate facet joint and adjacent segment degeneration. Artificial disc replacements have been developed as an alternative to fusion.

[Material removal after anterio-posterior spondylodesis -- necessity of posterior instrumentation removal after osseous fusion].

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.

[New bone formation by extracorporeal shock waves. Dependence of induction on energy flux density].

Background: The purpose of this study was to test the hypothesis that shock waves can induce new bone formation even without cortical fractures and periosteal detachment as suggested in the literature.

Methods: Extracorporeal shock waves with energy flux densities between 0 mJ/mm(2) (sham treatment) and 1.2 mJ/mm(2) were applied in vivo to the distal femoral region of rabbits (1500 pulses at 1 Hz frequency each).

Operative treatment for degenerative lumbar spinal canal stenosis.

The authors have made a retrospective study of a cohort of patients who underwent surgery for spinal stenosis. A total of 85 patients were surgically treated for spinal stenosis between 1993 and 1997, and 79 patients were available for re-evaluation. The average time of follow-up was 79 months.

Medium to long-term results with the cementless threaded Acetabular Munich II type cup.

Compared to pressfit cups, little information exists about the results of screwed cups in hip arthroplasty. 51 cementless or hybrid (cemented stem) primary total hip replacements with a cementless corundium blasted titaniumn alloy threaded Aesculap Munich II type cup were examined with a mean follow up of 7.9 years.

Low accuracy of stem implantation in THR using the CASPAR-system: anteversion measurements in 10 hips.

We studied 10 patients by means of pre- and postoperative CT who underwent computer-assisted total hip replacement using the CASPAR-system (OrthoMaquet GmbH, Rastatt, Germany). The anteversion angles of the stem and translational deviations measured after surgery were compared to the preoperatively planned ones as a quality control. We found an average difference of 7.

Anterior shoulder instability modifies glenoid subchondral bone density.

Subchondral bone mineralization is used as a morphologic marker for individual stress distribution of joints and therefore may help to distinguish variations of glenohumeral contact. Therefore, an in vivo analysis was done to evaluate glenoid stress distribution in anterior glenohumeral instability by computed tomography osteoabsorptiometry. Patients with recurrent anterior glenohumeral dislocation, seven of posttraumatic and six of atraumatic origin, and an intact rotator cuff were grouped retrospectively and compared with healthy, age-matched shoulder specimens from cadavers (n = 13).

[An update on thrombosis prophylaxis in orthopaedic and accident surgery].

The prevention of deep venous thrombosis has become a routine in orthopaedic surgery. While the necessity for prophylaxis is not questioned, its practice is still a matter of controversy. The development of new anticoagulants increases the variety of prophylactic methods but leads to a need for additional information.

Influence of minimally invasive surgery on implant positioning and the functional outcome for medial unicompartmental knee arthroplasty.

We describe postoperative functional outcome and accuracy of implant position in 38 cases after unicompartmental knee arthroplasty with the Oxford knee prosthesis with a standard open approach compared with 30 cases with a minimally invasive approach. Patients with the minimally invasive approach had significantly better functional results, with an average Hospital for Special Surgery scores of 92 (range, 81-98) compared with 78 (range, 24-99). Range of motion 1 year postoperatively was better in the minimally invasive group (113 degrees vs 107 degrees ), but the results were not statistically significant.

Long-term results of high tibial osteotomy for medial osteoarthritis of the knee.

We reviewed retrospectively the results in patients who had undergone one hundred and four high tibial lateral osteotomies. The operations were all performed between 1985 and 1993. Each one of fifty men and forty nine women demonstrated a varus deformity of the knee with a coexistent medial osteoarthritis.

The sublabral foramen: does it affect stress distribution on the anterior glenoid?

Even though it is believed that a sublabral foramen (SF) requires no treatment, no objective data are available to establish whether this condition bears a relationship to anterior-inferior glenohumeral instability. Therefore, the influence on glenoid subchondral bone mineralization of an isolated SF was investigated, because the individual distribution of subchondral bone mineralization may be used as an indirect parameter for long-term stress distribution of joints. Two age- and side-matched groups of healthy glenohumeral specimens with SF (n = 10, aged 37-85 years) and without SF (n = 10, aged 36-86 years) were examined by computed tomography osteoabsorptiometry.

Quantitative assessment of angiogenesis in murine antigen-induced arthritis by intravital fluorescence microscopy.

Inhibition of angiogenesis might be a therapeutic approach to prevent joint destruction caused by the overgrowing synovial tissue during chronic joint inflammation. The aim of this study was to investigate angiogenesis in the knee joint of mice with antigen-induced arthritis (AIA) by means of intravital microscopy. In 14 mice (C57BL6/129Sv) intravital microscopic assessment was performed on day 8 after AIA induction in two groups (controls, AIA).

[Influence of selective versus nonselective inhibitors of nitric oxide synthases on synovial microcirculation of the knee joint of the mouse in vivo].

Nitric oxide production by the inducible NO-synthase in the synovium and chondrocytes is known to be enhanced during chronic joint inflammation and aseptic loosening of joint prostheses. Due to the distinct side effects of non-selective NO-inhibitors on the macro- and microhemodynamics, we investigated the in vivo changes after selective (N-iminoethyl-L-lysine (NIL)) versus non-selective NO-synthase inhibition (NG-nitro-L-arginine methyl ester (L-NAME)) in the synovium of the mouse knee joint. Our results show a significant decrease in the functional capillary density and an increase in the leukocyte accumulation after L-NAME injection.

Tunnel enlargement and changes in synovial fluid cytokine profile following anterior cruciate ligament reconstruction with patellar tendon and hamstring tendon autografts.

There is growing evidence that cytokines such as tumor necrosis factor (TNF) alpha, interleukin (IL) 1beta, IL-6, bone morphogenetic proteins (BMP), and nitric oxide (NO) play an important role in the pathogenesis of bone tunnel enlargement following anterior cruciate ligament (ACL) reconstruction. Furthermore, the release of these mediators has been considered a possible reason for the higher incidence of bone tunnel enlargement following hamstring tendon (HST) than following patellar tendon (PT) ACL reconstruction observed in several studies. In this investigation synovial fluid samples from 13 patients were collected immediately before (24+/-7 days after ACL rupture) and 7 days after ACL surgery and values of TNF-alpha, IL-1beta, IL-6, NO, and BMP-2 were analyzed.

[Chronic recurrent multifocal osteomyelitis].

Chronic recurrent multifocal osteomyelitis (CRMO) is a rare, inflammatory, skeletal disease of unknown origin, which mainly affects children and adolescents in terms of cleido-spondylo-metaphysal skeletal inflammation. Only 10% of the patients are older than 20 years. To date, only about 200 cases have been reported in the literature.

Effects of ibandronate on inflammation in mouse antigen-induced arthritis.

Objective: To investigate the effects of ibandronate, a novel aminobisphosphonate, on inflammation as well as leukocyte-endothelial cell interaction in mouse antigen-induced arthritis (AiA).

Material And Treatment: 36 Balb/c mice were subcutaneously injected with 160 microg/kg of ibandronate once per day beginning at day 7 until day 13 after induction of AiA.

Methods: The severity of arthritis was assessed by changes of the transverse knee joint diameter.

[Inflammatory responses to wear particles in vivo: a novel model in the murine knee joint].

Although it is now widely recognized that the inflammatory response to implant wear particles plays an important role in aseptic loosening of total joint replacements, the precise mechanisms of this process remain unclear. The aim of this study was to establish an animal model for the study of the adverse response to particulate wear debris and the effects on the synovial microcirculation as well as the leukocyte-endothelial cell interaction in the murine knee joint in vivo. Balb/c mice were injected with 50 microl of a 0.

Resurfacing knee arthroplasty in patients with allergic sensitivity to metals.

Background: The problem of metal sensitivity (Ni, Cr, and Co) in arthroplasty is still unsolved. To prevent the risk of allergy in cases with proved metal allergy in an epicutaneous test, a Natural Knee total knee arthroplasty, made totally from titanium (Ti-6Al-4V) and polyethylene, can be implanted. The results of this device have to be compared to the results of normal knee arthroplasty designed with a femoral component out of CrCoNi alloy.

Irregular rotation and shift of computer-assisted femoral stem implantation in THA--an experimental study.

Introduction: The two available computer-assisted surgery robotic systems consist of a preoperative planning computer workstation and an industrial robot with a high speed milling device. During the computed tomography (CT) scan of the hip and the ipsilateral knee for planning the hip arthroplasty, the patient's movements are registered by a bar that is fixed at the patient's leg along its axis. Despite the companies' claim that a high accuracy of implant position can be achieved by this method, misplacements of implants are reported in the literature.

Age-related changes of the glenoid labrum in normal shoulders.

A growing number of labral changes are described in the literature. The purpose of this study was to evaluate the glenoid and labrum of normal shoulders at different ages and characterize any apparent age-dependent changes. We analyzed 32 normal cadaveric shoulders with a mean age of 57 years (range, 18-89 years).