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Biomedical subjects

H J Refior

Publications and source records attributed to H J Refior.

At least 37 records · Page 2Linked to original sources
PubMed2002

Subchondral mineralization patterns of the glenoid after tear of the supraspinatus.

Clinical experience has shown that in many cases of rupture of the supraspinatus tendon the head of the humerus shifts upward against the acromion. This implicates alterations in the stress acting on the joint surface. Accordingly, this should be reflected by changes in the distribution of the subchondral mineralization on the glenoid. Computed tomography osteoabsorptiometry was used to evaluate the distribution patterns on the subchondral bone plate of the glenoid in 67 human shoulders. The position of the two most frequent density maxima was determined by a standard procedure. In macroscopically normal specimens (n = 24) every case had an anterosuperior density maximum and the majority (75%) also had a posterior positioned maximum. In some instances a third maximum, placed centrally (17%) or in an anteroinferior position (4%) was seen. In shoulders with a torn supraspinatus tendon (n = 43) a third density maximum frequently appeared in the center of the glenoid (42%); however, most notable was a significant change of the posterior maximum position toward central and superior. With increasing size of the tendon defect an extension of the shift of the posterior maximum (superiorly and centrally) was observed in contrast to the constant anterior maximum. The changes in the distribution of glenoid subchondral bone mineralization in shoulders with a supraspinatus tear must be regarded as a morphologic parameter for the altered long-term stress acting on the joint surface.

Aged↗
PubMed2002

Long-term results after ankle arthrodesis: clinical, radiological, gait analytical aspects.

In a retrospective study the results of operatively treated ankle joints were critically discussed. In a period from January 1, 1977 to December 31, 1994, a total of 35 arthrodeses were carried out. Seventeen patients were followed up clinically, radiologically and with a gait analysis. Not only the radiological surgical result was of interest, but also the heel-toe movement of the stiffened foot in the individually adapted orthopedic footwear compared to standard footwear. A significantly improved heel-toe movement was found in orthopedic shoes, although there is a reduction of movement in the hindfoot in the sagittal plane.

Adult↗
PubMed2002

Influence of extracorporeal shock-wave application on normal bone in an animal model in vivo. Scintigraphy, MRI and histopathology.

There is little information about the effects of extracorporeal shock-wave application (ESWA) on normal bone physiology. We have therefore investigated the effects of ESWA on intact distal rabbit femora in vivo. The animals received 1500 shock-wave pulses each of different energy flux densities (EFD) on either the left or right femur or remained untreated. The effects were studied by bone scintigraphy, MRI and histopathological examination. Ten days after ESWA (0.5 mJ/mm2 and 0.9 mJ/mm2 EFD), local blood flow and bone metabolism were decreased, but were increased 28 days after ESWA (0.9 mJ/mm2). One day after ESWA with 0.9 mJ/mm2 EFD but not with 0.5 mJ/mm2, there were signs of soft-tissue oedema, epiperiosteal fluid and bone-marrow oedema on MRI. In addition, deposits of haemosiderin were found epiperiosteally and within the marrow cavity ten days after ESWA. We conclude that ESWA with both 0.5 mJ/mm2 and 0.9 mJ/mm2 EFD affected the normal bone physiology in the distal rabbit femur. Considerable damaging side-effects were observed with 0.9 mJ/mm2 EFD on periosteal soft tissue and tissue within the bone-marrow cavity.

Animals↗
PubMed2001

Exacerbation of antigen-induced arthritis in inducible nitric oxide synthase-deficient mice.

OBJECTIVE: Inhibition of nitric oxide (NO) produced by inducible NO synthase (iNOS) is suggested to be beneficial in experimental arthritis. Although NO is important for the integrity of the microcirculation, the effects of inhibition of iNOS on the synovial microcirculation are not currently known. This study investigated the synovial microcirculation and leukocyte-endothelial cell interactions in iNOS-deficient mice with antigen-induced arthritis (AIA) and compared these findings with disease severity. METHODS: Fourteen homozygous iNOS-/- and 14 iNOS+/+ mice were used. The severity of AIA was assessed by measuring knee joint swelling and by histologic scoring. The number of rolling and adherent leukocytes was quantitatively analyzed in synovial microvessels using intravital microscopy of intraarticular synovial tissue. Nitrite/nitrate concentrations were measured, and the expression of iNOS, E- and P-selectin, intercellular adhesion molecule 1, and vascular cell adhesion molecule 1 (VCAM-1) was assessed by immunohistochemistry. RESULTS: In iNOS+/+ animals with AIA, the plasma concentration of nitrite/nitrate was increased 3-fold and iNOS expression was detected in cells of the joint. Swelling of the knee joint as well as leukocyte infiltration were enhanced in the iNOS-/- arthritic animals compared with iNOS+/+ mice with AIA. AIA-associated leukocyte-endothelial cell interaction in synovial postcapillary venules was more pronounced in iNOS-/-, compared with iNOS+/+, arthritic mice. A strong expression of P-selectin and VCAM-1 was observed in the iNOS-/- arthritic mice only. CONCLUSION: These data suggest that NO production by iNOS in vivo has antiinflammatory effects in experimental arthritis, by mediating a reduction in leukocyte adhesion and infiltration.

Animals↗
PubMed2001

The value of desoxypyridinoline in the diagnostics of loosened arthroplasty.

According to several reports in the last few years, desoxypyridinoline (Dpd) in urine increases significantly in cases of loosened arthroplasty. Therefore, this marker was suggested as useful in the diagnostics of implant loosening. In this study, the level of Dpd was determined in 69 patients with arthroplasty of the hip or the knee joint. Thirty-four of these patients received revision surgery following implant loosening. In 35 of these 69 patients, there were no clinical or radiological signs of loosening (control group). The mean age of the patients with loosened implants (22 women, 13 men) was 67.9 years and of the control group (22 women, 12 men) 66.9 years. In the group with arthroplastic loosening, as well as in the control group, 14 patients had increased levels of Dpd. There were 20 patients in the group with loosened arthroplasty and 19 patients in the control group that had normal levels of Dpd. The female patients had a mean Dpd level of 8.6 nmol/mmol creatinine (4.3-24 nmol/mmol creatinine) in the urine in cases of loosening and 10.1 nmol/mmol creatinine (2-33 nmol/mmol creatinine) in the control group. The male patients had a mean Dpd level of 7.8 nmol/mmol creatinine (3.2-19.2 nmol/mmol creatinine) in the urine in cases of loosening and 5.8 nmol/mmol creatinine (0.3-11.7 nmol/mmol creatinine) in the control group. In conclusion there was no significant increase in Dpd in patients with implant loosening compared with the control group. Furthermore, older patients often suffer from diseases causing increased bone resorption that may falsify the test results. We cannot confirm that Dpd is helpful in the diagnostics and screening of implant loosening.

Adult↗
PubMed2001

On the impact of calcified deposits within the rotator cuff tendons in shoulders of patients with shoulder pain and dysfunction.

We wanted to prove the hypothesis that calcified deposits within the rotator cuff tendons are merely an epiphenomenon of complex morphological alterations in the shoulders of patients with shoulder pain and dysfunction. The shoulders of 92 patients with calcified deposits within the rotator cuff tendons as noted on plain radiographs were investigated by means of magnetic resonance imaging (MRI; mean age of patient 51.1 years), as well as the shoulders of 28 age- and sex-matched patients with similar clinical symptoms but without any signs of such calcified deposits on plain radiographs. The MRI protocol comprised a coronal, oblique, T1-weighted, spin-echo sequence, a T2-weighted, turbo spin-echo sequence, a sagittal, oblique, T2-weighted, turbo spin-echo sequence, and an axial, T1-weighted, spin-echo sequence. Furthermore, a coronal, oblique, short tau-inversion recovery sequence and a gradient echo sequence were used. The results were compared with data from healthy, asymptomatic volunteers as reported in the literature. The MRI investigations showed no substantial differences between patients with or without calcified deposits within the rotator cuff tendons, but distinct differences between such patients and healthy, asymptomatic volunteers. For patients with shoulder pain, shoulder dysfunction, and calcified deposits within the rotator cuff tendons, these calcified deposits are most probably not the main cause of the clinical symptoms. Rather, it seems to be useful to consider the results of MRI investigations whenever planning therapeutic procedures for patients with shoulder pain and dysfunction, irrespective of whether or not there are signs of calcified deposits within the rotator cuff tendons on plain radiographs.

Adult↗
PubMed2001

Extracorporeal shock-wave therapy for chronic lateral tennis elbow--prediction of outcome by imaging.

Today the clinical use of extracorporeal shockwave application (ESWA) for the treatment of lateral tennis elbow is hampered by the lack of results from randomized controlled trials and of predictive parameters of clinical outcome. The present prospective study aimed to provide the latter by means of magnetic resonance imaging (MRI). Twenty-three female and 19 male patients with unilateral chronic tennis elbow of the dominant site were clinically examined before and after repetitive low-energy ESWA. MRI was performed before ESWA to evaluate signal intensity changes or contrast enhancement of the common extensor tendon and the lateral epicondyle. After ESWA (mean follow-up period 18.6 months for all patients), clinical evaluation showed a significantly better mean clinical performance after ESWA than before treatment. Interestingly, male patients showed a significantly better mean clinical performance after ESWA than female patients, and male and female patients differed significantly in the signal intensity of the common extension tendon cross-section and tendon thickening on MRI. For female patients, MRI scans could be applied for predicting a positive clinical outcome of ESWA. This study reports the first indication of predictability of positive clinical outcome of the treatment of chronic lateral tennis elbow by ESWA using imaging prior to treatment. This may serve as an important step towards overcoming the therapeutic nihilism with respect to the non-operative management of this condition recently in the literature.

Adult↗
PubMed2001

Impaired tensile strength after shock-wave application in an animal model of tendon calcification.

Extracorporeal shock-wave application facilitates dissolution of rotator cuff calcifications. Therefore, disappearance or disintegration of tendon calcifications by shock waves might be appropriate for any kind of tendon calcification. Here, shock waves with various energy flux densities were applied to the mineralized medial gastrocnemius tendon of turkeys as an animal model. After application of shock waves in vivo, with energy flux density of 0.6 mJ/mm(2), histologic examination and microradiography did not show dissolution or disintegration of tendon calcifications. After shock-wave application in vitro, even for energy flux density of 1.2 mJ/mm(2) neither dissolution nor disintegration of tendon calcifications were observed. Biomechanical testing revealed significant impairment of tensile strength following shock-wave application in vitro, with energy flux density of 1.2 mJ/mm(2), but not with 0.6 mJ/mm(2). These results are important for considerations of clinical extracorporeal shock-wave application on tendon calcifications, as well as on tendon ossifications.

Animals↗
PubMed2001

Oxaceprol, an atypical inhibitor of inflammation, reduces leukocyte adherence in mouse antigen-induced arthritis.

Oxaceprol (N-acetyl-L-hydroxyproline), an atypical inhibitor of inflammation, is an established drug forjoint disease without serious side-effects. Recent studies have emphasized that oxaceprol has an effect on the microcirculation. Since the exact mechanism of action remains unclear, the aim of our study was to investigate the leukocyte-endothelial cell interactions in oxaceprol-treated mice with antigen-induced arthritis (AiA) using intravital microscopy. In our study, Balb/c mice were allocated to 4 groups (n 7, 8, 8, 8): 2 control groups with saline or oxaceprol and 2 groups of arthritic animals which received saline or oxaceprol (100 mg/kg twice a day intraperitoneally). The severity of arthritis was quantified by the transverse knee joint diameter. For the intravital fluorescence microscopy measurements on day 10 after inducing arthritis, the patella tendon was partily resected to visualize the intraarticular synovial tissue of the knee joint. The number of rolling and adherent leukocytes as well as RBC velocity and functional capillary density (FCD) were quantified in synovial microvessels. Furthermore, leukocyte infiltration was determined in the histological sections with an established score. No significant changes in mean arterial blood pressure or functional capillary density were found in any of the groups. However, the leukocyte rolling fraction and number of leukocytes adherent to the endothelium were increased in postcapillary venules of the synovium in arthritic animals (0.16 to 0.31, 78 cells/mm2 to 220 cells/mm2). In animals with AiA treated with oxaceprol, leukocyte adherence and swelling were significantly reduced in comparison to the arthritic animals treated with saline. Furthermore, the histological score showed less leukocyte infiltration in the oxaceprol treated arthritic animals. Thus, oxaceprol reduces leukocyte adherence in vivo and leukocyte infiltration in mouse AiA, indicating an effect on synovial microcirculation.

Animals↗
PubMed2001

Pigmented villonodular synovitis. Review of 20 cases.

OBJECTIVE: Pigmented villonodular synovitis (PVS) is a rare aggressive lesion. Inclusion of this disease in the differential diagnosis of rheumatoid arthritis can lead to early diagnosis and treatment. In this retrospective study we evaluated diagnostic procedures, therapies, and outcomes of PVS. METHODS: Twenty surgically treated cases of PVS were evaluated: joint, 16; tenosynovial, 3; and bursa, one. The 20 patients had undergone the following surgeries: 4 total synovectomies, 2 subtotal synovectomies, eight arthroscopically assisted resections, 4 resections of extraarticular lesions, and 2 arthroplasties. The mean followup was 17.5 mo (1-54). RESULTS: At diagnosis, pain was present in 19 of 20 cases. Joint swelling or a tumor was found in 11 cases, and 12 patients complained of repeated joint effusions. The mean duration of symptoms was 23.8 mo (range 1-144). Half the cases had a nodular pattern and the other half a diffuse pattern. The most common location of PVS was the knee (14 patients). Surgical treatment before admission did not always lead to an accurate diagnosis. For example, in 2 patients, arthroscopy did not reveal PVS. In 2 patients a soft tissue sarcoma was suggested. In 3 patients, the diagnosis was made incidentally with arthroscopy or arthroplasty. On radiographs, bone lesions were seen in 8 cases; in 13 of 17 cases the diagnosis was by magnetic resonance imaging (MRI). After surgery 17 patients stayed free of recurrence, 14 without symptoms. One patient who had an incidental diagnosis of PVS has a synovectomy planned as a second procedure. One patient awaits a second dorsal procedure after a ventral knee synovectomy. One patient shows recurrent disease 33 mo after resection of a nodular knee lesion. CONCLUSION: PVS should be included in the differential diagnosis of any arthritis. MRI is the most effective diagnostic tool in identifying PVS. The treatment of PVS consists of surgical excision in sound tissue. A total synovectomy should be the treatment of choice in diffuse disease. From the literature, nonsurgical therapies, such as steroid injections, 90Y synoviorthesis, or external beam radiation, seem to be of benefit in selected patients.

Adolescent↗
PubMed2000

Chondromyxoid fibroma of bone.

Chondromyxoid fibroma is a benign, although potentially aggressive tumor, with a cartilage-like matrix, accounting for approximately 1% of all bone tumors. It usually affects the metaphyseal region of long bones of patients in their first or second decade of life. An additional peak of incidence has been observed between 50 and 70 years of age. Three cases are presented here: 10-, 13-, and 52-year-old patients, with lesions in the proximal tibia, the proximal humerus, and the proximal femur, respectively. The literature is reviewed in terms of clinical behavior, diagnostic procedures, prognostic factors, treatment, and outcome. Preferred treatment is complete local excision with tumor-free margins. Intralesional curettage with or without local adjuvants shows a local recurrence rate of approximately 25%. Radiation therapy may be useful in nonresectable cases but bears the well documented risk of radiation-induced malignancies.

Adolescent↗
PubMed2000

Operative or conservative treatment of the acutely torn anterior cruciate ligament in middle-aged patients. A follow-up study of 133 patients between the ages of 40 and 59 years.

In all, 133 patients with an acute rupture of the anterior cruciate ligament (ACL) were reviewed (aged 40 to 59 years). Average follow-up was 29 +/- 10 months. Thirty-one patients underwent conservative therapy, 35 patients were treated by primary suture, while in 67 the primary suture was augmented with the semitendinosus tendon. The patients with primary repair and semitendinosus tendon augmentation showed significantly better results according to OAK and Lysholm scores, the Lachman test, pivot-shift testing, and KT-1000 arthrometer measurements than those treated conservatively or with primary suture. The physical activity level was significantly higher in the patients with augmented ACL repair than in the conservatively treated patients. There was no significant difference between the patients with augmented ACL repair and conservative treatment in the assessment of range of motion, while the patients with primary suture had a significantly greater loss of flexion than those in the other two treatment groups. Increasing age was not found to have a negative effect on either operative or conservative treatment. The results indicate that patients between the ages of 40 and 59 years can be treated successfully by ACL surgery.

Adult↗
PubMed2000

[A new resorbable bone-cartilage replacement transplant. Results of an animal experiment study].

Hyaline cartilage is thought to be unable to regenerate. All efforts so far--including autologous chondrocyte cell transplantation--to reconstruct cartilage defects in joints have not been totally convincing. However, mesenchymal cells are able to differentiate into chondrocytes under mechanical pressure conditions. In this study, an open porous resorbable two-layer "bioimplant" was constructed in which mechanical pressure was exerted onto mesenchymal cells when migrated into the open porous structure of the bioimplant. Differentiation of the cells into chondrocytes was thus induced. The bioimplants were implanted into the medial condyles of nine rabbits and left in place for eight or twelve weeks, respectively. In seven of these cases, cartilage formation was found, in contrary to the controls in which only connective tissue and bone had grown into the empty holes. The new bioimplants have proven their effectiveness in cartilage defect repair and might evolve in the future as a new alternative treatment of full thickness defects of joint surfaces.

Absorbable Implants↗
PubMed2000

Shockwave application in calcifying tendinitis of the shoulder--prediction of outcome by imaging.

This prospective study examined 62 patients (65 shoulders) with chronic courses of calcifying tendinitis of the shoulder before and after low-energy extracorporeal shockwave application (ESWA) in order to identify variables associated with the outcome of this treatment. Before ESWA, radiographs and contrast-enhanced magnetic resonance imaging (MRI) of the affected shoulders were obtained in order to document the size and morphology of the calcifications and the contrast media reactions in areas of interest (deposit, synovia, bursae), respectively. In addition, a clinical evaluation was performed. After ESWA (mean follow-up 18.2 months), clinical evaluations of all 65 shoulders revealed an increase in the Constant score from 44% to 78% (p < 0.0001). While size (p = 0.61) and morphology (p = 0.7) of the deposits before ESWA were not associated with the clinical outcome, negative contrast reactions around the deposits (p) = 0.0001), synovia (p = 0.0049) and bursae (p < 0.01) were associated with improved clinical outcomes. After the total study group was divided into two groups, one with Constant scores > or = 75% (n = 43) and the other with scores < 75% (n = 22), the positive predictive value (ppv), specificity (sp) and sensitivity (se) were determined for the negative reaction around the deposit (ppv: 0.94; sp: 0.95; se: 0.38), synovia (ppv: 0.84; sp: 0.82; se: 0.49) and bursae (ppv: 0.86; sp: 0.86; se: 0.44). In 5 cases (7.7%), surgery of the affected shoulder during the follow-up period was performed. No major side-effects were seen in the study group. In conclusion, our results suggest that in patients with chronic calcifying tendinitis, the absence of contrast enhancement, especially around the deposit, is a strong predictive parameter of a positive clinical outcome of ESWA.

Adult↗
PubMed2000

Malignant hemangiopericytoma of the bone.

Hemangiopericytoma is a rare vascular tumor of pericyte origin with variable malignant potential. Very rarely, this tumor occurs as a primary bone lesion. We present a case of a highly malignant hemangiopericytoma of the proximal tibia. Current therapy consists of radical resection of the tumor with postoperative radiation therapy being recommended. Chemotherapy seems to be useful in disseminated disease. The prognosis correlates to the histological grading of the tumor. Early or late recurrence and distant metastases with fatal outcome, as shown in our case study, are not uncommon.

Amputation, Surgical↗