Complications associated with opening wedge high tibial osteotomy--A review of the literature and of 15 years of experience

BACKGROUND

Complication rates following opening wedge high tibial osteotomy (OWHTO) is an issue that has not been comprehensively addressed in current literature.

METHODS

We performed a retrospective study of local patients who underwent OWHTO for isolated medial compartment knee osteoarthritis from 1997 to 2013. We analysed survivorship and complication rates and compared this to a literature review of previously reported data.

RESULTS

One hundred and fifteen patients met the inclusion criteria. Mean follow-up=8.4 years. Mean age=47 (range 32 to 62). Mean Body Mass Index (BMI)=29.1 (range 20.3 to 40.2). Devices used consisted of Tomofix (72%), Puddu plate (21%) and Orthofix (seven percent) (no significant differences in age/sex/BMI). Wedge defects were filled with autologous graft (30%), Chronos (35%) or left empty (35%). Five years survival rate (without requiring conversion to arthroplasty)=80%. Overall complication rate=31%. Twenty five percent of patients suffered 36 complications including minor wound infections (9.6%), major wound infections (3.5%), metalwork irritation necessitating plate removal (seven percent), non-union requiring revision (4.3%), vascular injury (1.7%), compartment syndrome (0.9%), and other minor complications (four percent). No thromboembolic complications were observed.

CONCLUSION

No significant differences existed in complication rates following OWHTO relative to BMI, implant type, type of bone graft used or patient age at surgery. When the complications from OWHTO were analysed closely they appear higher than previously reported in the literature; however serious complications appear rare. LEVEL OF EVIDENCE 3: Retrospective cohort study.

The outcome of all-inside meniscal repair with relation to previous anterior cruciate ligament reconstruction

BACKGROUND

Arthroscopically assisted all-inside meniscal repair has become a popular treatment for meniscal tears. Previous studies have suggested a beneficial effect of concomitant anterior cruciate ligament reconstruction on meniscal repair outcomes. The effect of prior cruciate ligament reconstruction (predating the meniscal injury) on meniscal repair success is unreported. The aim of this study was to assess the success of meniscal repair in our practice. Further aims were to analyze the effect of concomitant- and past-anterior cruciate ligament reconstruction on meniscal repair outcomes.

METHODS

Retrospective review of all patients undergoing arthroscopic meniscal repair during a 53 month period was performed. Mean followup was 13.5 months (mean 6-50). The primary outcome measure was meniscal reoperation.

RESULTS

Sixteen of 104 patients required reoperation, giving an overall meniscal repair success rate of 85%. Patients undergoing concomitant anterior cruciate ligament reconstruction enjoyed significantly improved outcomes (91%, p=0.049), while those with a past history of anterior cruciate ligament reconstruction had significantly worse meniscal repair success rates (63%, p=0.016).

CONCLUSIONS

Arthroscopic meniscal repair in a selected patient group offers good success rates, especially when performed with concomitant anterior cruciate ligament reconstruction. We have identified a subgroup of patients, those with a past history of anterior cruciate ligament reconstruction predating the meniscal injury, who appear to have relatively poor outcomes from meniscal repair. Potential reasons for this finding are discussed.

LEVEL OF EVIDENCE

Level IV, case series.

Autoantibodies against inosine-5'-monophosphate dehydrogenase 2--characteristics and prevalence in patients with HCV-infection

BACKGROUND

Indirect immunofluorescence (IIFT) on in house HEp-2 cell preparations revealed a novel antibody giving a granular cytoplasmic pattern not described before, which on two commercial cell preparations revealed a "rings and rods" pattern. This pattern was also observed in four HCV-RNA carriers and prompted the identification of the reactive antigen and the evaluation of the antibody prevalence in HCV-RNA carriers and control groups.

METHODS

The antigen's molecular weight was determined by radioimmunoprecipitation of 35S-methionine labeled cell proteins. Expression library screening and sequencing was performed by standard techniques using an oligo(dT)-primed human HeLa cell cDNA expression library. Antibodies against the novel antigen Inositol-5'-monophosphatdehydrogenase 2 (IMPDH2) were analyzed by IIFT, western blot, line blot, and radioimmunoprecipitation assay (RIPA). IIFT was performed on commercial HEp-2 cells and cells cultivated in house for 24 - 60 hours, with or without the IMPDH2 inhibitors mycophenolic acid (MPA) or ribavirin, and subjected to various fixation conditions. Western and line blots were performed with IMPDH2 synthesized in E. coli, RIPA with 35S-methionine-IMPDH2 from in vitro transcription/translation products. Sera screened were positive for HCV-RNA (108), HBV-DNA (100), anti-mitochondrial (31), anti-actin (42), and anti-nuclear antibodies (51) and negative for HCV-RNA (100) and blood donors (100).

RESULTS

IMPDH2 is capable of considerable intracellular rearrangements (upon action of inhibitors like MPA and ribavirin), which explains the contrasting immunofluorescence patterns in cells from different sources. By RIPA, proven to be the sole assay suitable for screening of anti-IMPDH2 in human sera, autoantibodies were found in 35.2% of HCV-RNA carriers and in low concentrations in 31% of anti-actin positive patients suspicious of autoimmune hepatitis. Antibodies reacted preferentially with conformational epitopes. Compared to the low concentration of anti-IMPDH2 found in other disease groups, high antibody concentrations were observed in HCV-RNA carriers.

CONCLUSIONS

The common occurrence of anti-IMPDH2 in HCV-RNA carriers may be related to ribavirin therapy, causing intracellular aggregation of IMPDH2 thereby altering its immunogenicity. In this study the "rods and rings" immunofluorescence pattern observed could be ascribed to anti-IMPDH2. Anti-IMPDH2 may cause difficulties in interpretation of immunofluorescence patterns in routine autoantibody testing.

Evaluation of patients with a painful total knee replacement

Evaluation of patients with painful total knee replacement requires a thorough clinical examination and relevant investigations in order to reach a diagnosis. Awareness of the common and uncommon problems leading to painful total knee replacement is useful in the diagnostic approach. This review article aims to act as a guide to the evaluation of patients with painful total knee replacement.

Nucleotide sequence of a new HLA-DQB1 allele, DQB1*03033

HLA-genotyping by sequencing of the corresponding polymerase chain reaction (PCR) product allow the identification of a new HLA-DQB1 allele, DQB1*03033. To confirm the finding the entire exon 2 was sequenced.

Hepatitis B virus genome is organized into nucleosomes in the nucleus of the infected cell

Hepatitis B virus (HBV) nucleoprotein complexes were isolated from nuclei of the human hepatoblastoma cell line HepG2.2.15. Under conditions of physiological ionic strength, the complexes sedimented at a rate corresponding to about 82 S. They contained viral DNA, histone, and nonhistone proteins. For DNA a circular, covalently closed structure was shown both by CsCl gradient centrifugation and electron microscopy. Spread preparations revealed the typical "beads-on-a-string" appearance of nucleosomally organized DNA. The average number of nucleosomes was 18, resulting in a biochemical repeat unit of HBV chromatin of approximately 180 base pairs of DNA. This value was confirmed by experiments analyzing the structure of the HBV chromatin by the use of micrococcal nuclease. Electron microscopy demonstrated that exposure to high ionic strength conditions resulted in removal of nucleosomes from the complexes, but also revealed proteinaceous structures remaining bound to viral DNA molecules. The nature of these residual proteins is discussed. Since native nucleoprotein complexes could be precipitated with HBV-core antibodies, core protein appeared to be one of the nonhistone proteins.

Molecular genetic analyses of a 376-kilodalton Golgi complex membrane protein (giantin)

Molecular genetic analyses of a 376-kDa Golgi complex (GC) membrane protein (giantin) are described. The immunoglobulin G fraction of a human serum containing antibodies against GC antigens as revealed by indirect immunofluorescence microscopy with Hep-2 cells was used to screen a HeLa cDNA expression library, yielding four overlapping cross-hybridizing clones. Additional cDNA clones were retrieved from a lambda gt11 human thyroid cDNA library or generated by reverse transcriptase-mediated PCR from HeLa cell mRNA. Alignment of the clones resulted in a consensus cDNA of 10,300 bp encoding a protein of 376 kDa. The corresponding mRNA with a size of about 10 kb was detected by Northern (RNA) blotting of HeLa, Hep-G2, and Jurkat cell RNA. Sequence analyses of the protein revealed an extraordinarily high content of heptad repeats with the probability of forming coiled coils similar to the proteins of the myosin family. Five overlapping recombinant proteins covering the entire sequence were synthesized and used for antibody production in rabbits and for affinity purification of human and rabbit antibodies. Indirect immunofluorescence experiments also done with brefeldin A-treated Hep-2 and Pt K1 cells revealed an identical GC staining of both the affinity-purified human and rabbit antibodies. Double labeling experiments with antibodies against the GC marker mannosidase II as well as immunoelectron microscopic studies confirmed the localization of the protein within the GC. A corresponding endogenous large-molecular-mass protein of about 390 kDa was found in [35S]methionine-labeled Hep-2 cell lysates as well as in GC-enriched subcellular fractions from rat liver. The protein as well as the recently described proteins golgin-95 and golgin-160 (M. J. Fritzler, J. C. Hamel, R. L. Ochs, and E. K. L. Chan, J. Exp. Med. 178:49-62, 1993) may belong to a new group of Golgi proteins with a high content of heptad repeats which may exert functions in scaffold formation or vesicle transport. As far as can be concluded from immunological and personally communicated partial cDNA sequence data, the protein seems to be identical with a 400-kDa Golgi protein (giantin) recently described (A. D. Linstedt and H. P. Hauri, Mol. Biol. Cell 4:679-693, 1993). Therefore, we agreed to adopt the name giantin.

In vitro experimental infection of primary human hepatocytes with hepatitis B virus

BACKGROUND/AIMS

Studies on the interaction of hepatitis B virus (HBV) with its host cell require a suitable tissue culture system. This study used primary adult hepatocytes from healthy human liver tissue to establish productive infection in vitro.

METHODS

Hepatocytes were inoculated overnight with HBV. Production of viral proteins was assessed by radioimmunoassay and by [35S]methionine labeling, and production of viral DNA was assessed by Southern blotting and endogenous polymerase assay.

RESULTS

Secretion of high levels of hepatitis B surface antigen (HBsAg) and low levels of hepatitis B virus e antigen (HBeAg) into the medium was detectable 6 days after infection and reached maximum values after 12 days. Metabolic labeling showed production of viral proteins to be a result of de novo synthesis. The appearance of single-stranded HBV DNA in the cytoplasm of infected cells, typically present in immature cores, indicated viral replication. HBV DNA containing particles possessing an active viral DNA polymerase could be immunoprecipitated from the medium 12 days after infection. An antiserum specific for the preS1 region of the viral envelope was capable to block infection. Presence of dimethyl sulfoxide in the medium greatly improved the yield of viral proteins.

CONCLUSIONS

Primary adult human liver cells are competent for infection with HBV.

Macrogolgin--a new 376 kD Golgi complex outer membrane protein as target of antibodies in patients with rheumatic diseases and HIV infections

Antibodies against the Golgi complex (GC) were found by indirect immunofluorescence microscopy in the serum of two patients with sclerodermia and Sjögren syndrome. Serum from one patient was used to screen clones from an oligo (dT) primed HeLa cDNA expression library. Four overlapping cross hybridizing clones (G1, G12, G13, G14) were found. One additional 5' clone (G15) was retrieved from a random primed lambda gt11 human thyroid cDNA library by nucleic acid hybridization, exploiting sequence information of clone G12. Additional clones for both the 5' and 3' ends were generated by RF-PCR from HeLa cell mRNA. Alignment of the overlapping clones resulted in a consensus cDNA of 10,300 bp encoding a protein of 376 kD. A corresponding mRNA of about 10 kb was found in Northern blots of RNA from various cultured cells. The most distinct features of the protein were the extraordinarily high fraction of alpha-helical domains containing heptad repeats with the probability of forming coiled-coils and the structure similarities with the myosin family and the yeast intracellular transport protein USO1. Five overlapping cDNA fragments covering the entire open reading frame were used to synthesize recombinant proteins for affinity purification of the antibodies in the two patients' sera. By use of these affinity purified antibodies, staining of the GC of various cultured cell lines was reproduced. The antibody target was dissociated within 15 min after brefeldin A exposure of cultured cells, a phenomenon, which was fully reversible within 30 min after withdrawal of the drug. Sucrose step gradient separation of GC enriched microsomal fractions from rat liver showed a natural antigen of about 380 kD co-fractionating with the GC marker galactosyltransferase. KCl extraction, Triton X-114 partition, as well as trypsin digestion of microsomal fractions revealed that the hydrophilic protein has to be located on the cytoplasmatic surface of GC vesicles. Using the five blotted recombinant protein fragments, anti-GC antibodies were found in 18 of 164 (11%) HIV positive patients but in none of the 64 healthy controls. HIV patients as well as the two original patients showed a diverse antibody spectrum recognizing different epitopes of the recombinant proteins. The protein characterized herein, for which we propose the provisional name macrogolgin, constitutes the largest protein known so far associated with the GC.

The Kapandji procedure for post-traumatic problems

The Kapandji procedure was performed on 14 patients who presented with chronic pain at the distal radioulnar joint, limited forearm rotation or poor grip after an injury involving the distal radioulnar joint. Ten patients were able to resume their original occupation and leisure activities. Some complained of mild aching after heavy use. Postoperatively, grip strength on the affected side was, on average, 84 per cent that of the opposite side. Forearm rotation in the affected arm averaged 129 degrees before operation and 170 degrees afterwards, compared with 171 degrees on the normal side, while wrist flexion-extension averaged 129 degrees preoperatively, 126 degrees postoperatively and 148 degrees on the normal side. Four patients had less satisfactory results because of pain and a feeling of insecurity due to an unstable proximal ulna. However, two of these had severe residual problems in relation to the initial forearm component of the injury, the symptoms from which were difficult to separate from the distal radioulnar injury. Although the Kapandji procedure can yield excellent results, it is difficult to predict which patients will suffer from an unstable ulna.

The chronic myelocytic cell line K 562 contains minor (m) as well as major (M) ber/abl fusion mRNAs

By searching for additional chimeric bcr/abl transcripts in K 562 cells characterized by major (M) bcr/abl fusions, a new mRNA, a minor (m) bcr/abl transcript, was detected. A practical implication of this finding is that the K 562 cell line can be used as positive control for the detection by the polymerase chain reaction of both types of transcripts for the diagnosis of Philadelphia chromosome associated leukemias.

Integrated defective replication units of hepatitis B virus

Stable transformants of the human hepatoma cell line HepG2 were established that constitutively transcribe a DNA unit consisting of a stretch of hepatitis B virus DNA and of nonviral DNA conferring resistance to neomycin. Previously it had been shown that upon cotransfection of such transformants with replication-competent HBV DNA, transcripts of such units become reverse transcribed, demonstrating that DNA constructs can function as defective replication units. Transformed cell lines stably transcribing the defective replication units could be shown to use the transcriptional starts for the viral pregenome and for the large core antigen at a ratio of 9:1. Upon the induction of replicative processes in the transformed cells by transfection with replication-competent wild type (wt) DNA, defective pregenomes transcribed from the integrated state became included in the pool of replicating nucleic acids.

Defective replication units of hepatitis B virus

Templates for the synthesis of defective hepatitis B virus RNA pregenomes were constructed. Viral sequences in these constructs were replaced by the neomycin resistance gene. Deletions spanned up to 80% of the genome and did not include the cohesive end region. The size of the defective replication units was reduced up to half of the wild-type unit length. After cotransfection with replication competent wild-type DNA, defective pregenomes became included into the pool of replicating viral nucleic acids. A natural template for a defective pregenome was derived from the integrated state in a hepatocellular carcinoma. Owing to a deletion, this unit was devoid of the hepatitis B virus enhancer.

Replication of hepatitis B virus in a hepatocellular carcinoma

Hepatitis B virus transcripts and DNA from paired samples of neoplastic and nonneoplastic liver tissue of HBsAg seropositive patients were analyzed. The data obtained support the view that transcription of integrated DNA is frequent, both in neoplastic as well as in nonneoplastic liver tissue. In the case of one patient, integrated and free forms of hepatitis B virus DNA were detected in the tumor. Complete cycles of viral replication in this tumor were suggested by the following markers: (i) DNA and RNA intermediates expected to occur during replication of the viral genome, (ii) HBcAg and HBsAg, (iii) core and Dane particles. Viral DNA cloned from tumor tissue was proven to be replication competent in a transient replication assay. Five independent clones of viral DNA were established and found to be closely related at the nucleotide level. A preX open reading frame and a stop codon within preC were common features. In tissue surrounding the tumor, a nonreplicative state of virus infection prevailed, characterized by free viral DNA exclusively of the covalently closed, circular form. The replication of the viral DNA appeared to be blocked at the level of transcription.

Mouse monoclonal antibody directed against hepatitis B virus X protein synthesized in Escherichia coli: detection of reactive antigen in liver cell carcinoma and chronic hepatitis

A mouse monoclonal antibody directed against the protein product of the hepatitis B virus X open reading frame was prepared. This antibody was used to screen liver tissue sections from patients with chronic hepatitis (CH) and patients with liver cell carcinoma (LCC). Reactive antigen was detected by immunohistochemistry in about 30% auf the samples from CH patients and in about 80% of the samples from LCC patients regardless of whether tumor or surrounding nontumor tissue was analyzed. A predominant localization of the antigen in the cytoplasm was observed. In liver sections of CH patients the presence of HBx or HBx-related protein appeared to correlate with the presence of the classical viral antigens HBs- and/or HBcAg. A similar correlation was not found in liver or tumor tissue samples from LCC patients. The occurrence of X-monoclonal-antibody-reactive protein (Xarp) at a low frequency in liver tissue from patients without hepatitis B virus related disease suggests that Xarp in some cases may not be identical with the putative viral X antigen.

A viable HSV-1 mutant deleted in two nonessential major glycoproteins

A HSV-1 recombinant lacking the two major glycoproteins gC and gE was isolated from cells co-infected with mutants negative for only one of these glycoproteins. The deletions of the appropriate genes were shown to be the same as on the respective parental genomes. In cell culture, the gC/gE minus recombinant virus replicated to titers similar to those obtained with the gC minus parental strain.