Surface or full cementation of the tibial component in total knee arthroplasty: a matched-pair analysis of mid- to long-term results.

INTRODUCTION: Despite the clinical success of cemented TKA, aseptic loosening of the tibial component remains a potential long-term complication. Considering the constantly growing revision burden, there is a need for clarification regarding controversial views on primary fixation techniques. In this retrospective analysis, surface (SC) or full cementation (FC) of tibial components was compared in a matched-pair and long-term setting. METHODS: Matching pairs were identified in a patient series from 1989 to 1994. Hence, 25 primary TKA (SC) were compared to 42 TKA (FC). The study population included 34 patients with rheumatoid arthritis. Patients were matched in a 1:1.7 fashion according to age, gender and initial diagnosis. Outcome was assessed by multiple clinical parameters, detailed radiographic evaluation and survivorship analysis. RESULTS: Clinical follow-up (FU) was at 10.3 years (range 1.5-15.6) for the SC and 12 years (range 0.2-16.2) for the FC group. Survivorship at 10 years was 100 % for the surface cemented trays and 93.3 % (95 % CI 80.5-100) for the fully cemented implants considering aseptic loosening as endpoint (p = 0.3918). Improvement of the AKS Score was greater in the SC group (p = 0.044) and patients in this group were more satisfied (p = 0.013). For any other clinical parameter, no difference could be observed (p > 0.05). CONCLUSION: Results of this study showed no statistically significant difference regarding long-term survivorship for the two cementing techniques. This finding questions the claimed advantage of full cementation for tibial components. The presented data do not support the concern that surface cementation results in insufficient fixation in patients with rheumatoid arthritis.

[Five-year survival rate of the Allofit titanium press-fit cup]. / 5-Jahres-Ergebnisse der zementfreien Allofit(R)-Press-fit-Pfanne.

BACKGROUND: The Allofit titanium press-fit cup has become the best-selling cementless acetabular implant in Germany, with approximately 30,000 implants sold in 2007. However, only a limited number of scientific publications - mostly from the development centres in Austria - support this success on the market. METHODS: At our institution in 1999-2000, 174 total hip replacements were performed using the Allofit cementless press-fit cup. At a mean follow-up of 5.3 years (range 40-85 months), 154 patients were evaluated clinically and radiographically, representing a follow-up rate of 89%. RESULTS: The 5-year survival rate was 98.1% (95% CI: 95.8-100%), with revision for any reason as an end point. Three cups were revised (aseptic loosening with one, and two septic complications). The average Harris hip score was 89.1+/-13.7 in all unrevised patients. CONCLUSION: We confirm the excellent survival rates of the Allofit cup as reported by the development centres, supporting the ongoing use of the cup at our institution.

Follow-up of 11-16 years after modular fixed-bearing TKA.

To present representative data of long-term survivorship and clinical outcome for the PFC total knee arthroplasty (PFC-TKA). A consecutive series of 141 TKA was followed for a mean of 13 years (range, 11-16 years). Sixty-five knees were evaluated, 30 of these clinically and radiographically. Twenty-eight knees could only be assessed with the use of a questionnaire. Six patients were living in nursing homes. Fifty-four patients (65 knees) had died. Eleven had undergone a revision. One patient was considered lost to follow-up. With re-operation for any reason as the endpoint, the 10-year survival rate was 92% (n = 91 patients at risk), and the 14-year survival rate was 91% (n = 12). With aseptic loosening of the implant as the endpoint, the 10- and 14-year survival rates were 97%. The mean Knee Society and function scores were 76 and 48 points, respectively. In this multi-surgeon series modular fixed-bearing TKA had good clinical and radiographic results with excellent long-term survivorship.

[Short-term results after STAR total ankle replacement]. / Frühergebnisse nach Implantation der STAR-Sprunggelenkprothese.

BACKGROUND: This retrospective study was performed to investigate the clinical and radiological results after STAR total ankle replacement. MATERIAL AND METHODS: Between January 2000 and September 2004, 49 patients with an average age of 62.5 years underwent total ankle replacement with the STAR prosthesis. At an average follow-up of 30.4 months, 48 patients were examined clinically and radiologically. The Kofoed ankle score and the patients' subjective satisfaction were evaluated. RESULTS: The operation improved the Kofoed ankle score significantly, from 28 to 86 points, 90% of the patients were satisfied with the results. The revision rate was 10%. CONCLUSION: The early results after implantation of the STAR ankle prosthesis are encouraging. With correct indication, a high rate of pain reduction and patient satisfaction can be achieved. The long-term benefit of this procedure has yet to be determined.

Consequences of telomerase inhibition by BIBR1532 on proliferation and chemosensitivity of chondrosarcoma cell lines.

PURPOSE: Human chondrosarcomas are generally resistant to conventional treatments like chemotherapy and radiotherapy. We investigated the effects of BIBR1532, an inhibitor of telomerase on chondrosarcoma cells in vitro. METHODS: Telomerase activity, telomere lengths, growth kinetics and chemosensitivity were analyzed in chondrosarcoma cell lines treated with BIBR1532. RESULTS: BIBR1532 treatment resulted in telomerase inhibition, decrease of telomere length and reduction of growth capacity of telomerase positive chondrosarcoma cells. Although resistant to cisplatin, telomerase positive cells were sensitive to paclitaxel, which rapidly induced telomere erosion. CONCLUSION: Targeting of telomeres might represent a valid strategy for the (re-)sensitization of chemoresistant chondrosarcomas.

[Total knee arthroplasty - GPs' views in Germany: a questionnaire-based study]. / Beurteilung des Verfahrens der Knieendoprothetik durch deutsche Hausärzte: Eine Fragebogenstudie.

To assess general knowledge and individual views of general practitioners (GPs) on total knee arthroplasty (TKA), we conducted a questionnaire-based survey involving 170 GPs in Germany. Eighty-one GPs returned the questionnaire. They treat a mean of 10.6+/-8.3 patients with TKA. General knowledge can be estimated as good. Compared with the data in the literature, GPs assessed the rate of satisfied patients as lower and the risk for revision surgery as higher. The mean risk of potential complications (infection, instability, persistent pain) in association with TKA was estimated correctly. Seventy-eight percent of GPs consider an allergic reaction to the implant or bone cement as problematic. The number of cases per year, personal experience with the surgeon, and - less important - local accessibility are important factors for GPs when recommending an operating centre to a patient.A broad spectrum of individual responses indicates the need to improve the information transfer between orthopaedic surgeons and referring GPs.

[Total hip replacement--GPs' views in Germany. A questionnaire-based study]. / Beurteilung des Verfahrens Hüftendoprothetik durch deutsche Hausärzte. Eine Fragebogenstudie.

To assess the general knowledge and individual views of general practitioners (GPs) on total hip arthroplasty (THA), we performed a questionnaire-based survey involving 200 GPs in Germany.Ninety-four GPs returned the questionnaire. They had treated a mean of 37.7+/-38.6 patients (range 0-300) with THA. Their general knowledge can be estimated as good. They assessed the potential for complications in association with THA as higher than that reported in the literature. If the GPs had been exposed to more complications in their practices, they estimated a lower patient satisfaction rate 10 years after surgery and were less satisfied with the indications given by their operating colleagues.A broad spectrum of individual responses indicates the need to improve information transfer between orthopaedic surgeons and referring GPs.

[Computed tomography of the musculoskeletal system]. / Computertomographie des Muskuloskelettalsystems.

Computed tomography (CT) is an important diagnostic modality in the work-up of musculoskeletal diseases. Just as projection radiography and magnetic resonance imaging, it has specific possible uses. As a tool to guide interventional and surgical procedures, it is a significant imaging technique. The technical development of multislice spiral CT in recent years has contributed considerably to increasing the diagnostic quality of CT. In particular, the possibilities for depicting the findings with methods for secondary image reconstruction have been decidedly improved.

Influence of the design of the prosthesis on the outcome after hemiarthroplasty of the shoulder in displaced fractures of the head of the humerus.

We reviewed 39 patients with displaced three- and four-part fractures of the humerus. In 21 patients (group A) we had used an anatomical prosthesis for the humeral head and in 18 (group B) an implant designed for fractures. When followed up at a mean of 29.3 months after surgery the overall Constant score was 51.9 points; in group A it was 51.5 and in group B 52.4 points. The subjective satisfaction of the patients was assessed using a numerical rating scale and was similar in both groups. In group A complete healing of the tuberosities was found in 29% and 50% in group B. Partial integration was seen in 29% of group A and in only one patient in group B, while resorption was noted in 43% of group A and 44% of group B. The functional outcome was significantly better in patients with complete or partial healing of the tuberosities (p=0.022). The specific trauma prosthesis did not lead to better healing of the tuberosities. The difference in clinical outcome obtained by the two designs did not reach statistical significance.

[Intraoperative extracorporeal irradiation and replantation in local treatment of primary malignant bone tumors]. / Intraoperative extrakorporale Irradiation und Replantation (IEIR) in der lokalen Behandlung primär maligner Knochentumoren.

In 13 patients with primary malignant bone tumors (10 Ewing's sarcoma, 1 parosteal osteosarcoma, 1 adamantinoma recurrence, and 1 MFH) local therapy was performed as intraoperative extracorporeal irradiation and replantation (IEIR) of the involved bone segment (5 tibia, 2 femur, and 6 pelvis). Of the 13 patients (69%), 9 are alive at the time of the follow-up (5 CDF, 4 AWM(treated)) and 4 patients died of disease (DOD). Up to now during the follow-up of 32 months (6-57), no local recurrence was observed in the replanted bone segments. The complication rate was very high (18 complications in 11 of the 13 patients, including 6 cases with complication V degrees according to Ruggieri with loss of the reconstruction). The typical complication is severe local infection necessitating removal of the replant. In cases of mechanical failure, the replanted segment could mostly be preserved by surgical revision and autologous bone grafting. If serious complications can be managed or avoided, functional results can be achieved. IEIR must be seen as an extraordinary reconstruction procedure in cases where established procedures such as endoprosthesis, biological reconstructions, or rotationplasties cannot be used or are refused by the patient.

Postacute management of patients with spinal cord injury due to metastatic tumour disease: survival and efficacy of rehabilitation.

STUDY DESIGN: Retrospective study utilising clinical records and public administration databases. OBJECTIVES: This study was performed to analyse the clinical presentation and survival rate of individuals with spinal cord injury (SCI) due to spinal metastasis after primary treatment, and to evaluate the efficacy of rehabilitative efforts. SETTING: Spinal Cord Injury Unit, University Hospital, Heidelberg. METHODS: A total of 68 consecutive patients were included. Demographics, clinical data, tumour type, level and completeness of SCI, initial treatment, functional independence measure (FIM) and survival time were derived from hospital and public administration databases. Cox regression and fuzzy logic rule generation were used for statistical analysis. RESULTS: Of the 68 patients, 66 patients died 11 months (median, interquartile range (IQR) 4-29 months) after the onset of neurological symptoms at an average age of 58 years. The functional independence measure (FIM) score describing the general clinical and functional status proved to be the most reliable prognostic factor of survival. Other more specific parameters (eg tumour type or level of lesion) did not have such an impact. In total, 51 patients completed the rehabilitation programme within 50 days (median, IQR 27-99 days). The FIM score improved from 62 at admission to 84 at discharge. CONCLUSION: The clinical and functional status is a valuable prognostic factor for survival. Since institutionalised rehabilitative efforts are effective, this group of patients should be accepted into such a program.

ERalpha gene expression in human primary osteoblasts: evidence for the expression of two receptor proteins.

The beneficial influence of E2 in the maintenance of healthy bone is well recognized. However, the way in which the actions of this hormone are mediated is less clearly understood. Western blot analysis of ERalpha in osteoblasts clearly demonstrated that the well characterized 66-kDa ERalpha was only one of the ERalpha isoforms present. Here we describe a 46-kDa isoform of ERalpha, expressed at a level similar to the 66-kDa isoform, that is also present in human primary osteoblasts. This shorter isoform is generated by alternative splicing of an ERalpha gene product, which results in exon 1 being skipped with a start codon in exon 2 used to initiate translation of the protein. Consequently, the transactivation domain AF-1 of this ERalpha isoform is absent. Functional analysis revealed that human (h)ERalpha46 is able to heterodimerize with the full-length ERalpha and also with ERbeta. Further, a DNA-binding complex that corresponds to hERalpha46 is detectable in human osteoblasts. We have shown that hERalpha46 is a strong inhibitor of hERalpha66 when they are coexpressed in the human osteosarcoma cell line SaOs. As a functional consequence, proliferation of the transfected cells is inhibited when increasing amounts of hERalpha46 are cotransfected with hERalpha66. In addition to human bone, the expression of the alternatively spliced ERalpha mRNA variant is also detectable in bone of ERalpha knockout mice. These data suggest that, in osteoblasts, E2 can act in part through an ERalpha isoform that is markedly different from the 66-kDa receptor. The expression of two ERalpha protein isoforms may account, in part, for the differential action that estrogens and estrogen analogs have in different tissues. In particular, the current models of the action of estrogens should be reevaluated to take account of the presence of at least two ERalpha protein isoforms in bone and perhaps in other tissues.

[Post-traumatic loss of function and malunion of the elbow]. / Die posttraumatische Funktionsstörung und Fehlstellung des kindlichen Ellenbogens.

Post-traumatic contracture and malunion of the elbow in pediatric patients may result from a combination of injury-related, diagnostic-related and therapy-related factors. Typical pediatric elbow injuries are associated with different patterns of these risk factors. Etiological differentiation allows for initial risk prediction, improves diagnostic awareness and provides adequate treatment in order to prevent unsatisfactory results.

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.

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.

[Prevalence of rotator cuff defects in dislocated fractures of the humerus head in elderly patients]. / Die Prävalenz von Rotatorenmanschettendefekten bei der dislozierten Humeruskopffraktur des älteren Patienten.

Humeral head fractures are commonly found in elderly patients. A high rate of spontaneous rotator cuff tears in this patient group may endanger good results following surgical treatment. 70 patients > 65 years with dislocated humeral head fractures were prospectively studied and treated surgically following a standardised treatment protocol. In all cases the rotator cuff was examined intraoperatively. A tear of the rotator cuff was documented in 4 cases (5%). The prevalence of rotator cuff tears in elderly patients with dislocated humeral head fractures is significantly smaller than expected referring to magnetic resonance-, sonographic and cadaveric studies of same-age patients without fracture. Therefore the rotator cuff may serve as retention anchor for the surgical treatment of dislocated humeral head fractures in elderly patients.

Complications of scoliosis surgery in children with myelomeningocele.

The purpose of the present study was to evaluate whether the high incidence of complications in scoliosis surgery in myelomeningocele (MMC) could be attributed to the surgical technique and whether improvements were possible. Between 1984 and 1996, 77 patients with MMC and scoliosis were treated surgically. The clinical and radiological follow-up ranged from 1 to 10 years with a mean follow-up of 3.6 years. The mean age at time of surgery was 12 years 8 months. The average preoperative scoliosis measured 90.20 degrees and was corrected by 47%. The first four patients were stabilized with Harrington rods after anterior correction with a Zielke device (group 1). Twenty-five patients were operated only from posterior, using Cotrel-Dubousset (CD) instrumentation (group 2). In 13 patients an anterior release and discectomy was performed prior to CD posterior instrumentation (group 3). In 26 patients (group 4) this was combined with an anterior instrumentation. The 9 patients of group 5 had congenital vertebral malformations which made a special treatment necessary. Complications could be divided into hardware problems, such as implant failure, dislocation or pseudarthrosis, infections, anesthetic, and neurologic complications. Hardware problems were seen in 29% of all patients. More hardware problems were seen with the Harrington rod (75%) and after solitary posterior instrumentation (30%). The occurrence of pseudarthrosis was dependent on the surgical technique, the extent of posterior spondylodesis, and lumbosacral fusion. Patients with hardware problems had a mean loss of correction of 49% compared to 13% in the other patients. Depending on the different surgical techniques a loss of more than 30% was seen in 12-75% of the cases. Early postoperative shunt failure occurred in four cases; delayed failure - after more than 1 year - in three cases. One patient died within 1 day due to an acute hydrocephalus, another died after 2 1/2 years because of chronic shunt insufficiency with herniation. Wound problems were not dependent on the surgical technique, but on the extent of posterior spondylodesis and the lumbosacral fusion. Based on this analysis we believe our current practice of instrumented anterior and posterior fusion is justified. Further, we are very careful to check shunt function prior to acute correction of spinal deformity.

Complete paraplegia due to multiple intracerebral and spinal cavernomas.

We report on a 29-year-old male patient with multiple intracerebral and spinal cavernomas. Bleeding in the thoracic cord at admission and additional bleeding which occurred 12 days later in the cervical cord resulted in complete paraplegia below thoracic level 4 (Th4). Four years earlier multiple cerebral cavernomas had been diagnosed by magnetic resonance imaging (MRI). Based upon reported cases in the literature multiple intracerebral and spinal cavernomas are exceptional. Additionally, the clinical presentation in our case is uncommon.

[Projections and fiber characteristics of sensory afferents of the anterior cruciate ligament in an animal experiment]. / Projektion und Faserqualität der sensiblen Afferenzen aus dem vorderen Kreuzband im Tierexperiment.

The sensory innervation of the rabbit anterior cruciate ligament was studied by retrograde tracing technique using wheat-germ-agglutinin-horseradish-peroxidase (WGA-HRP) and Fast Blue as neuronal tracers. Injection of the tracer into the ligament was followed by histo- and immunohistochemical investigation of labelled nerve cell bodies located in the dorsal root ganglia. In 4 animals we injected the tracer into the joint cavity to label general joint afferents. The segmental distribution of retrogradely labelled neurons following injection into the anterior cruciate ligament (L6, L7, S1) is significantly different from the distribution pattern after injection into the knee joint (L4-S2). Retrogradely labelled nerve cells innervating the anterior cruciate ligament were further investigated using immunohistochemical and morphometric analysis. The sensory innervation of the anterior cruciate ligament is therefore comprised of at least 2 different qualities of sensory afferent nerves: 1. Small neurones immunoreactive to the inflammatory peptide substance P most likely transmitting nociceptive information centrally (44%). 2. Large, presumably fast conducting A-fibre-afferents characterized by neurofilament proteins transmitting proprioceptive information from corpuscular mechanoreceptors (43%). The results of this study put further weight to the importance of the sensory role of the anterior cruciate ligament using neuroanatomical and immunohistochemical techniques.