Comparison of results of core decompression and intertrochanteric osteotomy for nontraumatic osteonecrosis of the femoral head using Cox regression and survivorship analysis.

Different surgical procedures have been recommended for osteonecrosis of the femoral head to prevent or delay the need for arthroplasty. Core decompression is a commonly used treatment in the early stages of the disease, but the published efficacy has varied markedly. Only a few comparisons of different techniques have been reported. The aim of this study was to evaluate and compare the results of 2 commonly used procedures, core decompression and intertrochanteric osteotomy, using Cox regression and survivorship analysis. A total of 177 cases with a mean age of 41 years at surgery were treated for osteonecrosis (94 core decompressions, 83 osteotomies). Any further surgery was defined as failure and endpoint. Significant risk factors for treatment failure were age > 40 years at surgery (P = .022), corticosteroid intake (P < .001), advanced stage of necrosis (Steinberg stage > or =III, P=.04), and core decompression (P = .084). To analyze the influence of the surgical procedure, patients with corticosteroid treatment were excluded, and survival analysis was performed. This analysis revealed survival rates of 74% after osteotomy and 78% after core decompression 6 years postoperatively in early, precollapse stages (P = .819). In advanced stages, the rate of survival for hips after core decompression was lower (56%) than in hips after osteotomy (76%) (P = .056). Our results indicate that core decompression may be as effective as intertrochanteric osteotomy in precollapse stages but is less traumatizing and is cost-effective. For postcollapse hips, intertrochanteric osteotomy should be considered.

Long term changes of the throwing arm of former elite javelin throwers.

The aim of this study was to determine long term changes in shoulder and elbow joints of former elite javelin throwers. Twenty-one elite javelin throwers were examined at an average of 19 years after the end of their high performance phase. Mean age at examination was 50 years. Functional assessment of both shoulders was determined by the Constant-score. The shoulder of the throwing arm was examined by magnetic resonance imaging. Both elbow joints were examined clinically and radiographically. Five athletes complained about transient shoulder pain in their throwing arm affecting activities of daily living, fourteen athletes had a deficit of internal rotation of at least ten degrees. Constant-scores of throwing arms were six points lower than those of non-throwing arms (P < 0.05). Complete ruptures and partial tears of the rotator cuff were frequent. Three athletes complained about transient elbow pain in their throwing arm affecting activities of daily living; ten athletes had a deficit of extension of more than five degrees. All dominant elbows had advanced arthrotic alterations (osteophytes, sclerosis) compared to the non-dominant side. Athletes who trained with weights of more than 3 kg had a significantly higher risk of degenerative changes than athletes who did not (P < 0.01). We therefore recommend to avoid throwing training with weights of more than 3 kg.

Long-term review of the lumbar spine in javelin throwers.

We studied 21 former top-class competitive javelin throwers to investigate radiological and clinical symptoms in the lumbar spine many years after the end of their athletic careers. The athletes underwent clinical and radiological examinations at an average of 20 years after retiring from athletics. The Hannover questionnaire was used to evaluate functional restrictions in daily living. Degenerative changes in the lumbar spine were more marked towards the caudal aspect of the spine. Ten athletes also had spondylolisthesis, but with little progression (< 15%) throughout the observation period. Athletes both with and without radiologically demonstrated spondylolisthesis, complained of no more back problems than the normal population (93% for athletes v 86% for controls). Slight progression followed their retirement from athletics.

Surgical management of paralytic scoliosis in myelomeningocele.

A retrospective analysis of 54 patients with paralytic scoliosis due to myelomeningocele, who underwent surgical treatment, was performed. The aim of this study was to compare different surgical techniques and to identify clinical parameters influencing primary and midterm results. Three surgical techniques were used: 1) group I, posterior fusion/instrumentation; 2) group II, anterior fusion/no instrumentation combined with posterior fusion/instrumentation; and 3) group III, anterior and posterior fusion/instrumentation. Average age at surgery was 13.1 years. A preoperative scoliosis angle of 90 degrees [interquartile range (25th-75th percentile) (IQR), 76-106 degrees] was primarily reduced to 38 degrees (IQR, 30-50 degrees). At final follow-up (mean, 3.3 years), correction deteriorated to 44 degrees (IQR, 38-65 degrees). The group III procedure resulted in a better midterm correction of scoliosis compared with group I (P = 0.02). The extension of anterior fusion correlated with primary and midterm correction of scoliosis (P < 0.03). Patients with a thoracic level of paralysis had a higher relative loss of correction compared with patients with a lumbar level (P < 0.06). This finding can be attributed mostly to group I patients (P = 0.011). Hardware complications occurred in 16 patients (30%). Relative loss of correction among these patients was high (P < 0.01) and relative midterm correction low (P = 0.001). We recommend anterior and posterior fusion, each with instrumentation for the treatment of paralytic scoliosis in myelomeningocele. In patients with a thoracic level of paralysis, the two-stage procedure is mandatory to reduce the risk of hardware complications and subsequent major loss of correction.

[Acupuncture treatment of low back pain]. / Akupunktur zur Behandlung von Schmerzen im Bereich der Lendenwirbelsäule.

OBJECTIVES: This prospective, non-controlled pilot-study examines the potential benefit of acupuncture in patients with low back pain and radicular symptoms. METHODS: 60 patients with low back pain and lumbar disc herniation diagnosed by magnetic resonance imaging or computed tomography were treated by acupuncture. Pain intensity was assessed before and after treatment on a 100 mm visual analogue scale. RESULTS: Intensity of low back pain dropped from 59 to 19 mm, and intensity of radicular pain from 64 to 12 mm. Three to twelve months after the end of acupuncture, 88% of patients were satisfied with treatment outcome. CONCLUSION: Acupuncture as a noninvasive treatment with very few complications is a promising therapeutical option of low back pain, especially when associated with radicular symptoms.

The effect of spinal fusion on the long-term outcome of idiopathic scoliosis. A case-control study.

We have investigated the effect of multisegmental spinal fusion on the long-term functional and radiological outcome in patients with scoliosis. We compared these patients both with those whose spine had not been fused, and with a control group. We studied 68 patients with idiopathic scoliosis (34 operative and 34 non-operative) who had been followed up for a minimum of five years after treatment. They were matched for age (mean 44 years) and Cobb angle (mean 54 degrees) at follow-up. An age- and gender-matched control group of 34 subjects was also recruited. All participants completed a questionnaire to assess spinal function and to grade the severity of back pain using a numerical rating scale. Radiographs of the spine were taken in the patients with scoliosis and lumbar degenerative changes were recorded. The spinal function scores for the patients with scoliosis who had had a fusion were similar to those who had not. Both scoliosis groups, however, had lower scores than the control group (p < 0.001). The frequency and severity of back pain were lower for patients with scoliosis and fusion than for those without, but higher for both scoliosis groups compared with the control group. Radiographs showed similar degenerative changes in both scoliosis groups.

Epidural corticosteroid injection in the conservative management of sciatica.

In this prospective randomized clinical trial, the results of epidural corticosteroid injections were evaluated in patients with lumbosciatic pain caused by herniated nucleus pulposus. Thirty-six patients with radicular lumbosciatic pain and positive straight leg raising test because of confirmed prolapsed intervertebral lumbar discs were randomized into two groups with (17 patients) and without (19 patients) epidural corticosteroid injection. Members of the treatment groups received three injections of 100 mg methylprednisolone in 10 mL bupivacaine 0.25% each. Additional therapy was standardized and identical in both groups. Followup examinations were performed at 2 weeks, 6 weeks, and 6 months. The examinations included pain level (visual analogue scale), straight leg raising test, and functional status (Hannover Functional Ability Questionnaire). At 2 weeks, patients receiving methylprednisolone injection showed a significant improvement in straight leg raising test results compared with patients in the control group. Results were better in the methylprednisolone group, although not statistically significant for pain relief and mobility. At 6 weeks and 6 months, pain relief, improvement of straight leg raising, and improvement of functional status showed no statistical significance. Epidural corticosteroid injections can be recommended as additional therapy only in the acute phase of the conservative management of lumbosciatic pain.

[Effect of extracorporeal shockwave administration on biological behavior of bone cells in vitro]. / Der Einfluss der extrakorporalen Stosswellenapplikation (ESWA) auf das biologische Verhalten von Knochenzellen in vitro.

AIM: Osteo-destructive effects as well as stimulation of bone growth are often described after extracorporeal shock-wave application (ESWA). A correlation between the applicated energy and outcome is assumed. The purpose of this study was to analyze, whether ESWA has an influence on growth and proliferation of bone cells in vitro. METHODS: Human cancellous bone was cultivated until a confluent cell layer had grown. 5 x 10(5) bone cells were transferred into U-formed tubes, centrifuged and covered with cultivation medium. Thereafter ESWA was applicated in a standardized manner. Number and intensity of ESWA were systematically combined (500, 1000, 2000 and 0.15, 0.26, 0.51 mJ/mm2 energy flux density--EFD, respectively). Ten samples per combination were analyzed. In addition, we examined an untreated control group. Survival, metabolism (alkaline phosphatase activity), type I collagene-synthesis as well as proliferation were determined. RESULTS: There is a decrease of survival after ESWA depending on the number of impulses and intensity (dose-dependent survival). Cell survival was significantly reduced to 40% after 2000 impulses with high energy rates. Metabolism of surviving cells is not altered by ESWA in comparison with controls. Depending on the number but not on the energy of impulses the type I collagene-synthesis of surviving cells decreased. Between the 3rd and the 8th day after ESWA proliferation increased significantly in cell cultures treated with 2000 impulses of medium or high energy rates. CONCLUSIONS: There is a direct relation between dose and effect for ESWA: A minimum number of impulses and EFD is needed to cause effects on bone-cells. This mainly depends on the numbers of impulses. Destruction of cells is a short-time effect of high shock-wave-doses, a medium-term effect is a cell-stimulation.

Influence of extracorporeal irradiation on the reintegration of autologous grafts of bone and joint. Study in a canine model.

We studied the effects of irradiation on the reintegration of autologous osteoarticular grafts over a period of 24 weeks in a canine model. In 16 foxhounds the medial femoral condyle was resected, irradiated and immediately replanted. In the control group resection and replantation were performed without irradiation. Reintegration was assessed by macroscopic analysis, histology, radiography and gait analysis. Reintegration was equal at 12 weeks, but significantly inferior in the irradiated group after 24 weeks with delayed bone remodelling. The articular cartilage showed modest degeneration. Conventional radiography and histology showed corresponding changes. Limb function was adequate but the gait was inferior in the treated group.

Core decompression in osteonecrosis of the femoral head: risk-factor-dependent outcome evaluation using survivorship analysis.

The results of core decompression of the femoral head in the treatment of osteonecrosis are analyzed. This study includes 94 hips in 74 patients with a follow-up time ranging between 18 months and 15 years (average 6 years). There had been no need for further surgery 2 years postoperatively in 85% of the hips with preoperative Steinberg stages 0, I and II when compared with 66% with preoperative stages III, IV and V. At 4 years postoperatively the corresponding figures are 73 compared to 55%; and 6 years postoperatively 69 compared to 49%. This difference was significant (P=0.0402). Further significant risk factors are corticosteroid administration, smoking and alcohol intake. The results of core decompression are good when the preoperative lesion is at Steinberg stage 0, I and II and the patient does not present with other risk factors. In cases with risk factors the outcome is significantly less good. The procedure is not indicated in the presence of advanced disease.

[Effectiveness of intra-articular application of hyaluronic acid on early forms of femoropatellar arthrosis--an experimental study in dogs]. / Wirksamkeit von intraartikulär applizierter Hyaluronsäure auf Frühformen der Femoropatellararthrose--Eine experimentelle Untersuchung an Hunden.

PURPOSE: We investigated the effects of intraarticularly applied hyaluronic acid on the cartilage-integrity with early-forms of retropatellar cartilage degeneration (chondromalacia patellae) in dogs. METHODS: We used the Pond-Nuki model (tenotomy and resection of the anterior cruciate ligament = ACL) in 27 dogs (foxhounds) (3 groups of 9 animals) PILOT STUDY: ACL-tenotomy and resection, no therapy, specimens retrieval after 3, 6, 12 weeks (3 animals each period). VERUM: ACL-tenotomy and resection, hyaluronic acid (start after 3, 6, 12 weeks), 5 injections in 4 weeks, specimens retrieval after 5 weeks following final injection (12, 15, 21 weeks postoperatively, 3 dogs each period). PLACEBO: same procedure as verum, but saline-injections. Specimens were taken from the medial/lateral patellar pole from both, the operated and the normal knee and examined histologically using various staining methods (HE, Azan, Toluidin, Masson-Goldner, Safranin-O). A modified Mankin score was used to grade cartilage degeneration. RESULTS: Our results demonstrate that the Pond-Nuki model is suitable to experimentally induce chondromalacia patellae. There were significantly less degenerative cartilage changes in the knees treated with hyaluronic acid compared to the placebo-group. CONCLUSION: Our results let assume that hyaluronic acid could be indicated i.e. after arthroscopically diagnosed early cartilage-degeneration, the final conclusions concerning the actual mechanisms and therapeutical effectiveness need however further prospective clinical and experimental investigations.

Increased urinary crosslink levels in aseptic loosening of total hip arthroplasty.

The diagnosis of aseptic loosening in total hip arthroplasty is predominantly based on clinical and radiographic evaluation. Loosening is usually associated with increased bone resorption at the interface. In this study we wanted to evaluate the diagnostic value of bone markers in aseptic loosening. We compared 50 patients with proven component loosening during surgery with 50 age-, sex-, and implant-matched patients without clinical or radiological signs of loosening. We measured serum markers of bone formation (bone-specific alkaline phosphatase, osteocalcin [OC], procollagen type I propeptides) and bone resorption (collagen n-telopeptide [NTX], deoxypyridinoline [DPYD], pyridinoline [PYD]). We found significantly increased levels of NTX, DPYD, PYD, and OC in the loosening group. The other markers showed no significant difference between both groups. We conclude that determination of urinary crosslinks may offer a new and valuable diagnostic method in the detection of aseptic loosening in total hip arthroplasty.

[Cementless hip prosthesis in inflammatory rheumatic diseases]. / Zementfreie Hüftendoprothetik bei entzündlich-rheumatischen Erkrankungen.

We compared the outcome of cementless hip arthroplasty in patients with chronic rheumatic diseases (cases) and patients with osteoarthritis (controls). Between 1985 and 1993 we implanted 26 cementless hips in 22 patients with Rheumatoid Arthritis, Psoriatic Arthritis or Ankylosing Spondylitis. From a pool of more than 600 patients with Osteoarthritis we chose 40 matched controls (41 hips). Matching variables were year of implantation, age, follow-up, height, weight, gender and type of implant. At follow-up (cases: 58 +/- 27 months; controls: 56 +/- 26 Monate) no signs of loosening or migration of the stem were found, neither in the cases nor in the controls. Loose and/or migrated cups were found in 4 patients with rheumatic diseases (after 44, 65, 65 and 107 months) and in 3 patients with osteoarthritis (after 63, 84 and 100 months). Two cups were revised within 18 months in the control group, in the case group one revision was necessary after 5 years. Loosening and revision rates did not differ significantly (p > 0.20). Clinically, those with Osteoarthritis had a better extension (p < 0.02), were more satisfied with their (artificial) hips (p < 0.05) and did better in some activities of daily living (climbing stairs, dressing, sitting/standing up). Within a mean follow-up of 5 years the results of patients with chronic rheumatic diseases seem to be comparable to those of a matched control-group of patients with Osteoarthritis. Differences between the groups concern areas, in which rheumatic patients are handicapped due to their chronic illness. Nevertheless, we need long-term-results, before we can recommend cementless implants for these patients.

[Biometric planning of clinical-orthopedic studies. The optimal test]. / Biometrische Planung klinisch-orthopädischer Studien. Der optimale Stichprobenumfang.

A determinant for the evidence of a clinical trial is the magnitude of the sample size. The proper sample size can be easily computed with the knowledge of alpha, power and effect size. Standard values for alpha and power in clinical trials are 5% and 90%, respectively. As a consequence, effect size is crucial for the sample size. The effect size has to be determined by the clinician according to medical considerations. Possible consequences of sample sizes that are either too small or too large are discussed with regard to the meaning of alpha, Power and effect size. Trials with improper small sample sizes have a high risk of false negative results, and may subsequently prevent the application of a possibly effective therapy. Trials with improper large sample sizes may result in statistically significant differences without any clinical relevance.

[Diagnosis of hip prosthesis loosening--sensitivity of clinical parameters]. / Diagnostik der Hüftendoprothesenlockerung--Sensitivität klinischer Parameter.

AIM: In order to establish a strategy for early diagnosis of aseptic loosening of total hip arthroplasty (THA) physical examination, patient's assessment and radiographs were analysed. METHOD: Pain, self assessment, physical examination and mobility were examined according to a standard examination protocol in 428 hips of 297 patients after cementless total hip arthroplasty (THA). These findings were compared with the radiographic finding of the hip. Sensitivity and specifity of objective and subjective parameters were analysed. RESULTS: The clinical outcome of THA's is assessed by pain and physical examination. Nearly all hip scores are based on these parameters. In this study sensitivity and specificity of all parameters analysed were unsatisfactory compared with the radiographic finding. Although we found some correlations between clinical and radiological data, clinical data alone are not sufficient for exclusion of THA loosening, especially for loosening of the acetabular component, as there was no clear distinction between the group of radiographically loosened (43 acetabular cups and 4 stems) and intact endoprostheses. CONCLUSION: We conclude, that physical examination and pain history are not sufficient to exclude loosening of cementless THA's. Radiographic examination is essential for the assessment of THA's, even in painfree patients.

[Use of new biochemical markers in diagnosis of aseptic hip endoprosthesis loosening]. / Der Einsatz neuer biochemischer Marker in der Diagnostik aseptischer Hüftendoprothesenlockerungen.

Aseptic loosening of endoprosthesis is the most important problem in total hip arthroplasty. The diagnosis of aseptic loosening is based on anamnesis, the clinical findings, the radiography and scintigraphy. Despite the multitude of diagnostic possibilities it is still a problem to get an exact and early diagnosis. The process of loosening in the bone interface always leads to a change of bone structure of the surrounding bone tissue. In a prospective study we measured biochemical markers of bone metabolism in serum and urine to evaluate a possible change occurring parallel to endoprotheic loosening. 37 patients with severe signs of loosening (later intraoperatively confirmed) and 30 patients without any clinical or radiological signs of loosening (control group) were induced. Gender, age and model of endoprosthesis were similar in both groups. Parameters of bone formation (osteocalcin, alkaline phosphatase, procollagen I C-terminal extension peptide) and bone resorption (Cross-linked n-terminal telopetide) were measured. The cross-linked n-terminal telopetide (NTX) was significant increased in the loosening group (p < 0.001). Of the measured bone formation markers only osteocalcin showed a significantly higher level in patients with endoprosthetic loosening (p < 0.002). All other measured parameters of the bone metabolism showed no significant differences between the both groups. Our results show, that biochemical markers can provide relevant information of endoprosthesic loosening. We are now analysing in a prospective longitudinal study whether these parameters are also suitable to detect early endoprosthetic loosening.

Middle-term results of threaded acetabular cups. High failure rates five years after surgery.

We report our results using three different threaded acetabular components (Mecring A, Mecring B and Weill) in 715 hips with a follow-up of between one and ten years (median: 99.1, 56.5, 38.3 months, respectively). All cups were implanted with one type of cementless stem. The clinical results were good or acceptable in about 70% of the hips, but signs of loosening with radiolucency and/or migration were found in 10.1%. Radiological evidence of loosening did not correlate significantly with the clinical outcome. Pain was not a reliable indicator of loosening and its absence sometimes allowed severe osteolysis to develop. Twenty-five hips were revised (3.5%) for aseptic loosening of the acetabular component. Kaplan-Meier estimates of the cumulative rate of failure showed a rapid increase five years after the initial operation, but no significant correlation with gender, age or weight. The high rate of failure indicates that further use of these acetabular components cannot be recommended. Annual radiographs are required to assess osteolysis even if the patients are free from pain.

Development of pathological lumbar kyphosis in myelomeningocele.

We analysed the cases of lumbar kyphosis in 151 (21%) of a series of 719 patients with myelomeningocele. Three different types were distinguished: paralytic, sharp-angled and congenital. In a cross-sectional and partly longitudinal study the size and magnitude of the kyphosis, the apex of the curve and the level of paralysis of each group were recorded and statistically analysed. Paralytic kyphosis (less than 90 degrees at birth) occurred in 44.4% and increased linearly during further development. Sharp-angled kyphosis (90 degrees or more at birth) was present in 38.4% and also showed a linear progression. In both types, progression seemed to depend also on the level of paralysis. Congenital kyphosis occurred in 13.9% and we could find no significant factor which correlated with progression.

Further investigations of the intraosseous pressure characteristics in necrotic lunates (Kienböck's disease).

To confirm the hypothesis that venous congestion plays a role in idiopathic lunate necrosis (Kienböck's disease), intraosseous pressure in 12 normal and 12 necrotic lunates was measured. Intraosseous pressure in the capitate of 12 healthy subjects served as reference measurement. The intraosseous pressure was recorded in neutral position and 60 degrees extension of the wrist under normotensive conditions and during venous stasis. In all groups, the mean intraosseous pressure rose significantly with extension of the wrist, with the largest increase being 92.3 mmHg for necrotic lunates, followed by 40.3 mmHg for normal lunates, 6.9 mmHg for normal capitates and during venous stasis, 26.6 mmHg for necrotic lunates, 26.1 mmHg for normal lunates, and 5.9 mmHg for normal capitates. In some necrotic lunates, the intraosseous pressure during extension exceeded the arterial blood pressure, which can be explained by mechanical deformation of the bone. In neutral position, no significant differences in pressure were found between normal lunates and capitates. A significant difference was found for venous stasis and extension. The intraosseous pressure rise in the normal lunate in extension was slightly higher than the pressure found during venous stasis. The intraosseous pressure differed significantly (by 56.9 mmHg) between normal and necrotic lunates in extension. These data support the hypothesis that impairment of venous drainage plays a role in lunate necrosis and that the lunate can be considered as a venous bone at risk.

[A prospective study of early diagnosis of lunate necrosis by means of MRI]. / Prospektive Studie zur Früherkennung der Lunatumnekrose mittels Kernspintomographie.

AIM: Early recognition of lunate necrosis by means of MRI. METHODS: 49 patients with typical symptoms and normal radiographs were examined. Coronary T1 and T2 weighted images were obtained. In addition, an attempt was made to quantify fluid shift and measure of bone marrow oedema by means of extreme T2 weighting (TR 5950 ms, TE 150 ms). RESULTS: Three instances of necrosis were found; in two cases it was possible to demonstrate marrow oedema. Oedema preceding necrosis could not be demonstrated by quantifying a grey scale. CONCLUSIONS: The pattern of pain in the region of the lunate is not typical and is usually not of bone origin. Early MRT will show lunate necrosis only rarely; nevertheless, the therapeutic consequences justify the examination if pain persists for several weeks. Extreme T2 weighting for quantifying a grey scale to demonstrate early marrow oedema has not proved useful. Our experience suggests that T2 weighting is adequate and is the method of choice for the early recognition of necrosis of the lunate.