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H J Refior

Publications and source records attributed to H J Refior.

At least 19 recordsLinked to original sources

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.

Adult↗

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). Patients were assessed before and 3, 6, and 12 months after treatment by a blinded investigator. RESULTS: After 3 months, the visual analog scale (VAS) score for back and leg pain was significantly reduced in the epidural neuroplasty group, and the need for pain medication was reduced in both groups. Furthermore, the VAS for back and leg pain as well as the Oswestry disability score were significantly reduced until 12 months after the procedure in contrast to the group that received conservative treatment. CONCLUSIONS: Epidural neuroplasty results in significant alleviation of pain and functional disability in patients with chronic low back pain and sciatica based on disc protrusion/prolapse or failed back surgery on a short-term basis as well as at 12 months of follow-up.

Adult↗

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. In this prospective study, the effects of disc replacement with the CHARITE Artificial Disc on facet joint loading and integrity were evaluated. Thirteen patients aged <50 years with symptomatic DDD were recruited. Computed tomography (CT) osteoabsorptiometry was performed prior to the implantation of the CHARITE Artificial Disc and six months after. With this technique, increases or decreases in facet joint loading and integrity are indicated by corresponding changes in subchondral bone density. Changes in the distribution of load alter the distribution of the areas of maximum bone density. Clinical outcome was also assessed at pre-operative and 6 and 12 month post-operative visits using the Visual Analogue Scale back and leg pain scores, the Oswestry Disability Index and the Short Form-36 (SF-36) questionnaire. The height of the intervertebral space at the operated level was monitored by lateral X-ray. Subchondral bone density was evaluated in the facet joints of all 13 patients at the operated level, 12 patients at the level above the operated segment, and five patients at the level below the operated segment. Quantitative measurements revealed no significant increases (> or =3%) in subchondral bone density of the facet joints at any level in any patient. Significant decreases (> or =3%) in subchondral bone density were measured at the operated level in 10/13 patients, at the level above the operated segment in 6/12 patients, and at the level below the operated segment in 3/5 patients. There were no changes in the distribution of the areas of maximum bone density in any of the studied facet joints at 6 months compared with pre-operative measurements. Clinical outcome scores were improved at 6 and 12 months compared with baseline. The mean intervertebral space height at the operated level was increased following implantation of the CHARITE Artificial Disc and was 1.8 times greater than the pre-operative height at both 6 and 12 months. In this study, replacement of degenerated intervertebral discs with the CHARITE Artificial Disc was not associated with increased loading of the facet joints at the operated or adjacent levels. Decreases in subchondral bone density may indicate reduced loading in the posterior column following disc replacement compared with loading in the pre-operative degenerated spine. Further study is required to establish the baseline for healthy subchondral bone density and to compare this baseline with long-term measurements in patients undergoing disc replacement.

Adult↗

[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 4.9 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.

Adult↗

[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). Oxytetracycline was injected on days 5-9 and the animals were sacrificed on day 10. Sections of both femora of all animals were investigated with broadband fluorescence microscopy and contact microradiography for new periosteal and endosteal bone, periosteal detachment, cortical fractures, and trabecular bone with callus. RESULTS: Shock waves with energy flux densities of 0.9 mJ/mm(2) and 1.2 mJ/mm(2) resulted in new periosteal bone formation in the presence of cortical fractures and periosteal detachment. After application of shock waves with energy flux density of 0.5 mJ/mm(2), clearly detectable signs of new periosteal bone formation were observed without cortical fractures or periosteal detachment. CONCLUSIONS: The results of this study challenge the current view in the literature that the creation of cortical fractures and periosteal detachment are prerequisites for new bone formation mediated by extracorporeal shock waves.

Animals↗

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. 23 of the patients were male and 28 patients were female. From these cups 22 were implanted on the right side and 29 on the left. The results were compared to 53 patients (28 male, 25 female, 29 right side, 24 left side) with the threaded Aesculap Munich I type cup, that has a smooth surface and a direct contact of bone with the polyethylene inlay. The mean follow up ws 10.2 years. The early and medium to long-term clinical and radiographic results show an encouraging improvement of the Merle d'Aubigné Score of the type II cup compared to the type I cup. Two of the Aesculap type Munich II cups had to be revised; four showed radiologic signs of loosening. In conclusion, the threaded Aesculap cup type Munich II seems to be a decisive advance in the development of threaded acetabular hip cups. The intermediate results exceed those from smooth-surface screwed rings and compare favourably with those from cemented cups and with those from cementless press-fit metal-backed cups.

Acetabulum↗

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). Synovial tissue was investigated by intravital fluorescence microscopy using FITC-dextran (150 kD). Quantitative assessment of vessel density was performed according to the following categories: functional capillary density (FCD, vessels <10 microm in diameter), functional vessel density (FVD, vessels >10 microm) and FVD of vessels with angiogenic criteria (convoluted vessels, abrupt changes of diameter, vessels which are generated by sprouting and progressively pruned and remodelled). Microvessel count was performed using immunohistochemistry. There was no significant difference in FCD between the control group (337 +/- 9 cm/cm2; mean +/- SEM) and the AIA group (359 +/- 13 cm/cm2). The density of vessels larger than 10 microm diameter was significantly increased in animals with AIA (135 +/- 10 vs. 61 +/- 5 cm/cm2 in control). The density of blood vessels with angiogenic criteria was enhanced in arthritic animals (79 +/- 17 vs. 12 +/- 2 cm/cm2 in control). There was a significant increase in the microvessel count in arthritic animals (297 +/- 25 vs. 133 +/- 16 mm(-2) in control). These findings demonstrate that angiogenesis in murine AIA can be assessed quantitatively using intravital microscopy. Further studies will address antiangiogenic strategies in AIA.

Animals↗

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. Furthermore, the incidence of bone tunnel enlargement was assessed using radiographs 38+/-7 weeks after surgery. Six patients underwent autologous HST ACL reconstruction, and in seven patients an PT autograft was used. In the overall patient population there were significantly higher synovial fluid concentrations of IL-6 and BMP-2 postoperatively than preoperatively; TNF-alpha showed a trend towards lower postoperative levels while IL-1beta and NO remained unchanged. The concentrations of NO, TNF-alpha, and IL-6 found in the present study were clearly higher than normal values given in the literature. Assessment of bone tunnel enlargement revealed an average increase in tibial tunnel width of 28.4+/-3.1% with comparable values for HST and PT ACL reconstructions. There was no significant correlation between bone tunnel enlargement and postoperative synovial fluid concentrations of TNF-alpha, IL-1beta, IL-6, NO, and BMP-2. However, all patients with bone tunnel enlargement had higher postoperative concentrations of TNF-alpha, IL-6, and NO in the synovial fluid. There were no significant differences in concentrations between HST and PT groups. In conclusion, we observed an association between tibial bone tunnel enlargement and elevated synovial fluid concentrations of IL-6, TNF-alpha, and NO 7 days after ACL surgery indicating the potential involvement of these biological mediators in the pathogenesis of bone tunnel enlargement. However, there was no difference between HST and PT ACL reconstructions regarding synovial fluid contents of IL-6, TNF-alpha, IL-1beta, NO, and BMP-2, suggesting a comparable biological response between these autografts following their use in ACL reconstruction.

Adult↗

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. The mechanical resistance of this alloy is much higher than that of titanium, and therefore it is the standard for the femoral components of most knee-resurfacing devices. METHODS: Thirty-five patients with a titanium Natural Knee were examined retrospectively after a mean follow-up of 2 years and 5 months (range 6 months to 5 years and 4 months). In comparison, 36 patients with a Genesis-I knee with a CrCoNi alloy femoral component were studied after a mean follow-up of 2 years and 4 months (range 8 months to 6 years and 2 months). RESULTS: In spite of the lower mechanical resistance of titanium, the Natural Knee showed better results (knee score 84.1 points, function score 77.7 points, HSS score 80.1 points, 82.9% excellent and good results) than the Genesis-I knee (knee score 80.6 points, function score 76.4 points, HSS score 76.4 points, 68.5% excellent and good results), although these differences had no statistical significance. CONCLUSIONS: The titanium Natural Knee prosthesis has proven to be a reliable knee joint replacement in the medium term.

Adult↗

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. MATERIALS AND METHODS: In an experimental study, a cadaver femoral bone was rotated during the CT scan strictly around this bar to simulate a rotational movement of the patient. Using the CT data, the planning of the hip stem and the following preparation of the femur by the robot was possible without detection of the patient's movements by the system. According to the system manual, the computer should stop the planning or give a warning in case of patient movement during the CT scan. RESULTS: The postoperative CT scan of the cadaver femoral bone revealed a rotary deviation and a shift of the stem compared with the original planning, caused by the rotation during the CT scan. CONCLUSION: We propose using a second bar during the CT scan to detect these movements and thus avoiding misplacement of the implant.

Arthroplasty, Replacement, Hip↗

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. For the intravital fluorescence microscopy measurements on day 14 after AiA induction, the patella tendon was partly resected to visualize the intraarticular synovial tissue of the knee joint. The number of rolling and adherent leukocytes as well as red blood cell (RBC) velocity and functional capillary density (FCD) were quantified in synovial microvessels. Furthermore, leukocyte infiltration in the synovium was determined in histological sections with an established score. RESULTS: Both fractions of rolling leukocytes (p = 0.016) as well as number of extravasated leukocytes (p = 0.004) were enhanced in control animals treated with ibandronate in comparison to animals which received saline. Arthritic animals with and without ibandronate treatment revealed an increased FCD (p = 0.006, p = 0.008), enhanced number of rolling ( p = 0.002, p = 0.001) and adherent leukocytes (p = 0.009, p = 0.007) and greater swelling of the left knee joint (p = 0.002, p = 0.001) when compared to control animals. No significant differences between arthritic animals and arthritic animals treated with ibandronate were found in any of the parameters assessed including leukocyte adherence, FCD, histology, and knee joint swelling. CONCLUSION: Ibandronate treatment of healthy mice was associated with an enhanced fraction of rolling leukocytes and increased numbers of extravasated leukocytes indicating a proinflammatory effect on the synovial microcirculation. In animals with a preexisting antigen-induced arthritis, however, ibandronate did not induce an exacerbation of joint inflammation and leukocyte adherence.

Animals↗

[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. In the course of the disease, the initial radiological signs are osteolysis followed by sclerosis and hyperostosis in the end stage. The histological investigations reveal chronic inflammatory infiltrates with lymphocytes and hyperostosis. Although the prognosis of CRMO, to our current understanding, is self limiting, serious complications have been reported such as pathological fractures and compression fractures of the spine. A recently recommended therapy scheme is based on the administration of azithromycin combined with calcitonin. We present the case of a 25 year old female patient who has suffered from CRMO for 1.5 years with the cervical spine and the manubrium sterni being affected. The current state of diagnosis, therapy, and prognostic outlook of this rare disease are discussed.

Adult↗

[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 0.5-microm polystyrene particle suspension (0.1% v/v) into the knee joint. The severity of the inflammatory response was evaluated at days 1, 2, 3, 5, 7 (acute), 21 (intermediate), and 63 (chronic) after particle injection. Histological examination as well as assessment of the synovial microcirculation using intravital microscopy was performed. For the intravital microscopy measurements, the patella tendon was partially resected for visualization of the synovial tissue of the knee joint and the fluorescent markers FITC-dextran and rhodamine 6G were injected intravenously. There was a significantly enhanced leukocyte-endothelial cell interaction beginning at day 3 after particle injection with a maximum in the acute phase (days 5-7) and a subsequent decline in the intermediate (day 21) and chronic (day 63) phases. Functional capillary density was significantly increased from day 3 until day 21 after particle application. The histological examination showed an inflammatory reaction that complied widely with the temporal course of the microvascular parameters and resembled the histological appearance of the synovial-like membrane around loose joint prostheses. A novel model was established for the qualitative and quantitative investigation of the particle-induced inflammatory response in the joint environment. It was shown for the first time that there is a significantly enhanced leukocyte-endothelial cell interaction in the synovial tissue after intra-articular particle injection. This model seems to be suitable for further investigations, e.g., dealing with the biocompatibility of different particle materials.

Animals↗

[The sublabral foramen. Congenital or an acquired variance?].

The sublabral foramen is considered to be a clinically asymptomatic, isolated variant of the anterior-superior capsulo-labral-complex. It may be observed during shoulder arthroscopy and may implicate problems in differential diagnosis of traumatic lesions. In an anatomic study on 89 macroscopically healthy shoulder specimens the age distribution and the incidence in relation to the varying shape of the glenoid as feasible factors of influence for a sublabral foramen (SF) were analyzed in order to elucidate the unknown pathogenesis of SF. In addition histologic sections of three SF samples were obtained. Mean age of the specimens with a sublabral foramen [n=20; 69 (37-84) years] was significantly higher (p=0.04) compared to samples without a sublabral foramen [n=69; 59 (18-94) years]. An increased incidence of a sublabral foramen in relation to a distinct shape of the glenoid could not be established although a prevalence of a glenoid with anterior notch was observed. The results indicate an age-related development of the sublabral foramen,thus in younger patients with an anterior-superior capsulolabral displacement local signs of trauma and involvement of the biceps anchor should be controlled before definitive diagnosis.

Adolescent↗

Internal hemipelvectomy and reconstruction with a megaprosthesis.

We treated nine consecutive patients by internal hemipelvectomy and reconstruction with custom-made megaprosthesis between 1990 and 1997. Four had a primary malignant bone or soft tissue tumour, one a recurrent benign giant cell tumour, three solitary metastatic bony lesions, and one a pelvic defect secondary to multiple revision procedures after total hip replacement. After a mean follow-up period of 62 (40-102) months five patients were still alive, including four of the eight patients with tumours. Three patients died as a result of the malignant disease, and one died of an infection related to the surgical treatment after 10-41 months. In two patients removal of the prosthesis was required due to infection, and six patients suffered various complications. One patient had an excellent outcome.

Adolescent↗

The relation between primary osteoarthritis of the trapeziometacarpal joint and supernumerary slips of the abductor pollicis longus tendon.

We have studied whether accessory abductor pollicis longus slips inserting into the thenar eminence or trapezium influence the incidence and severity of trapeziometacarpal joint osteoarthritis. The right first extensor compartment of 73 cadavers was dissected and trapeziometacarpal degeneration was graded macroscopically. The main abductor pollicis longus tendon which inserted at the metacarpal base was accompanied by supernumerary APL slips in 96% of cases. Thenar or trapezial slips occurred frequently but coexisted in only one case. The incidence of trapeziometacarpal arthritis was not influenced by the number of accessory slips or whether they inserted onto the thenar eminence or the trapezium.

Aged↗