The correlation between Salter's criteria for avascular necrosis of the femoral head and Kalamchi's prognostic classification following the treatment of developmental dysplasia of the hip

AIMS

The aim of this study was to evaluate the correlation between Salter's criteria and Kalamchi's classification of avascular necrosis in patients treated for developmental dysphasia of the hip (DDH).

PATIENTS AND METHODS

The study involved a retrospective analysis of 123 patients (123 hips) with DDH treated by operative and non-operative reduction before the age of two years, with a minimum follow-up of ten years. Salter's criteria (S1 to S4) were determined from radiographs obtained at one to two years post-reduction, whilst the Kalamchi grade was determined from radiographs obtained at ten or more years of age. Early post-reduction radiographs were also used to evaluate the centre-head distance discrepancy (CHDD) and the occurrence of a dome-shaped deformity of the proximal femoral metaphysis (D-shaped metaphysis). The prognosis was described as good (Kalamchi grade K0 or KI), fair (Kalamchi grade KII) or poor (Kalamchi grade KIII or KIV) for analysis and correlation with the early Salter criteria, CHDD and D-shaped metaphysis.

RESULTS

S1 and S2 criteria were predictive of a poor prognosis. The outcome following S3, S4 and S3 + S4 varied; 18 (40%) had a good prognosis, 17 (38%) a fair prognosis and ten (22%) a poor prognosis. A CHDD ≥ 10% and a D-shaped metaphysis were also predictive of a poor prognosis.

CONCLUSION

The Salter criteria were predictive of the Kalamchi grade of avascular necrosis in patients with DDH aged ten or more years after reduction of the hip. Cite this article: Bone Joint J 2017;99-B:1115-20.

The effects of radial shock waves on gene transfer in rabbit chondrocytes in vitro

OBJECTIVE

The purpose of this study was to develop a new technique of gene transfer utilizing radial shock waves. The effects of radial shock waves on gene transfer in rabbit chondrocytes were examined by varying the parameters of exposure conditions in vitro.

METHODS

Chondrocytes were obtained from New Zealand white rabbits and cultured in a monolayer. A luciferase-encoding gene expression vector, or vector alone, was added to chondrocyte cell suspensions, and the cells were then exposed to radial shock waves. Parameters such as pressure amplitude, number of pulses, frequency, and DNA concentration were varied, and luciferase activity was measured 48h after transfection. Transfection efficiency of radial shock waves was compared with the FuGENE6 transfection method using a green fluorescence protein (GFP)-encoding gene vector by fluorescent-activated cell sorter (FACS) analysis.

RESULTS

Radial shock wave exposure significantly increased luciferase activity over 140-fold as compared to the control under the optimal exposure conditions. Both pressure amplitude and number of pulses were relevant to transfection efficiency and cell viability, but frequency was not. Transfection efficiency increased in a dose-dependent manner with DNA concentration. FACS analysis showed 4.74% of GFP-encoding gene using radial shock waves. FuGENE6 transfection was almost similar in transfection efficiency to radial shock wave.

CONCLUSION

In spite of certain degree of cell disruption, radial shock waves significantly augmented reporter gene transfection in rabbit chondrocytes in vitro. Radial shock waves may potentially contribute to the treatment of the cartilage morbidities by enhancing the potency of tissue healing and gene transfection of growth factors.

Extracorporeal shock wave therapy improves motor dysfunction and pain originating from knee osteoarthritis in rats

OBJECTIVE

Although there have been several reports on the use of extracorporeal shock wave therapy (ESWT), the efficacy of ESWT for knee osteoarthritis (OA) has not been clarified. The aim of this study is to investigate the effect of ESWT on OA in a rat knee model.

METHODS

The rats were divided into three groups: (1) control, (2) OA, and (3) ESWT (knee OA+shock wave therapy). Behavioral analysis consisted of measuring the duration of walking on a treadmill. The expression of calcitonin gene-related peptide (CGRP) in dorsal root ganglion (DRG) neurons innervating the knee using immunohistochemistry was examined in the three groups at their peak time point on the treadmill.

RESULTS

Walking duration was significantly extended 4, 7 and 14 days after ESWT in rats with knee OA (peak time point: 4 days), again decreasing by days 21 and 28. Immunohistochemical studies revealed that the OA group had significantly higher percentages of CGRP positive neurons in the DRG than were found in the control group. In addition, ESWT reduced the ratio of CGRP positive DRG neurons in the OA model.

CONCLUSION

The improvement in walking ability and the reduction of CGRP positive neurons in DRG indicates that ESWT is a useful treatment for knee OA.

Treatment for developmental dysplasia of the hip using the Pavlik harness

We reviewed the medical records of 115 patients with 130 hips with developmental dysplasia with complete dislocation in the absence of a neuromuscular disorder, spontaneous reduction with a Pavlik harness, and a minimum of 14 years’ follow-up. The mean age at the time of harness application was 4.8 months (1 to 12) and the mean time spent in the harness was 6.1 months (3 to 12). A total of 108 hips (83.1%) were treated with the harness alone and supplementary surgery for residual acetabular dysplasia, as defined by an acetabular index > 30°, was performed in 22 hips (16.9%).

An overall satisfactory outcome (Severin grade I or II) was achieved in 119 hips (91.5%) at a mean follow-up of 16 years (14 to 32) with a follow-up rate of 75%. Avascular necrosis of the femoral head was noted in 16 hips (12.3%), seven of which (44%) underwent supplementary surgery and nine (56%) of which were classified as satisfactory. The acetabular index was the most reliable predictor of residual acetabular dysplasia.

A proposed prognostic formula for Perthes' disease

We retrospectively reviewed 145 patients with unilateral Perthes' disease and compared a quantitative analysis of early radiographic signs with a predicted prognosis at long-term followup. The average age of the patients at followup was 18.7 years (range, 16.2-27.5 years). We used the age at onset and three radiographic factors as independent variables for multiple regression analysis. The final radiographic results were based on a modified Stulberg's classification as the dependent variable. Fifty patients (35%) had a good outcome, 33 patients (23%) had a fair outcome, and 62 patients (42%) had a poor outcome. The most reliable formula in the stepwise multiple regression analysis was calculated as: y = -0.697 + 0.418 (age score) + 0.860 (involvement score) + 0.248 (subluxation score). The radiographic stage at first visit had no influence on the final results. Multifactorial assessment by combination of age at onset and two radiographic factors (epiphyseal involvement and subluxation) was the most reliable for predicting the prognosis. A score of 1.5 points or less predicted a good prognosis and a score of 2.6 or more indicated a poor prognosis.

LEVEL OF EVIDENCE

Prognostic study, Level IV (case series). See the Guidelines for Authors for a complete description of levels of evidence.

A paired study of Perthes’ disease comparing conservative and surgical treatment

We performed a paired study of mature patients with Perthes’ disease to compare the radiological results after treatment between conservatively- and surgically-treated groups. One patient was selected from each group to create the pairs for this study. Each pair was strictly matched for gender, body mass index, age at onset, stage at the first visit, necrotic area and radiological at-risk signs and each was assessed by comparing the values of six radiological measurements.

Eighteen pairs (36 hips) fitted the criteria. The radiological measurements which showed a statistically better result in the surgical groups were Mose’s method, the acetabular-head index and leg-length discrepancy. There were no statistical differences in the slope of the acetabular roof and the articulotrochanteric distance. Four hips in the conservative group were in Stulberg class II, five in class III and nine in class IV. In the surgical group, 13 were in Stulberg class II, four in class III and one in class IV.

We conclude that surgical treatment improved the sphericity of the femoral head and provided greater acetabular cover, but did not reform the acetabular roof.

It was noteworthy that a greater leg-length discrepancy and a smaller articulotrochanteric distance were not seen in the surgical group. Our study suggests that surgical treatment is preferable in patients with severe Perthes’ disease.

Shock wave application to rat skin induces degeneration and reinnervation of sensory nerve fibres

There have been several reports on the use of extracorporeal shock waves in the treatment of pseudarthrosis, calcifying tendinitis, and tendinopathies of the elbow. However, the pathomechanism of pain relief has not been clarified. To investigate the analgesic properties of shock wave application, we analyzed whether it produces morphologic changes in cutaneous nerve fibres. In normal rat skin, the epidermis is heavily innervated by nerve fibres immunoreactive for protein gene product (PGP) 9.5 and by some fibres immunoreactive for calcitonin gene-related peptide (CGRP). There was nearly complete degeneration of epidermal nerve fibres in the shock wave-treated skin, as indicated by the loss of immunoreactivity for PGP 9.5 or CGRP. Reinnervation of the epidermis occurred 2 weeks after treatment. These data show that relief of pain after shock wave application to the skin results from rapid degeneration of the intracutaneous nerve fibres.

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.

Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry using an inorganic particle matrix for small molecule analysis

Fine metal or metal oxide powder as an alternative to conventional organic matrices in matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOFMS) has been utilized successfully for lower molecular mass analytes, poly(ethylene glycol) 200 (PEG 200) and methyl stearate. Eleven kinds of particle, Al, Mn, Mo, Si, Sn, SnO2, TiO2, W, WO3, Zn and ZnO, were evaluated. The analyte was mixed with a metal or metal oxide powder (inorganic matrix) with particle diameter of tens of micrometers and liquid dispersant, followed by application to the sample target. Using a commercial MALDI-TOFMS instrument equipped with an internal 337 nm pulsed nitrogen laser, the analytes, PEG 200 and methyl stearate, were ionized as the alkali metal ion adducted molecules [M+Na]+ or [M+K]+ when the inorganic matrices Mn, Mo, Si, Sn, TiO2, W, WO3, Zn or ZnO were used. In the case of an Al matrix, PEG 200 was ionized as [M+K]+, whereas methyl stearate was ionized as [M+H]+ and [M+Al]+. These particles have potential as the matrix for MALDI. During our examination, however, only SnO2 particles did not ionize either PEG 200 or methyl stearate. Based on our protocol, when TiO2 powder was suspended with liquid paraffin, PEG 200 and methyl stearate gave their MALDI-TOF mass spectra with the lowest background noise and highest intensity. TiO2 powder seemed to be a broad potential matrix for low molecular mass polar or non-polar analytes. The results suggested that bulk particles caused rapid heating/vaporization processes and ionized analyte molecules under irradiation with a pulsed UV laser. The present method can be readily applied to obtain the low background noise MALDI-TOF mass spectra of small-sized compounds.

Effect of low-calcium hemodialysate on bone metabolism

In the present study, we investigated the kinetics of bone metabolism by determining serum bone metabolic markers and quantifying bone mineral density by dual-energy X-ray absorptiometry to clarify the effect of long-term use of low-calcium hemodialysate on bone metabolism. After changing the calcium concentration in the dialysate from 3.0 mEq/l to 2.5 mEq/l, serum intact parathyroid hormone level, serum highly sensitive parathyroid hormone level, and serum bone metabolic markers were determined in ten patients with chronic nondiabetic renal insufficiency during 1 year. The doses of an oral phosphate binder and activated vitamin D were carefully regulated to control serum ionized calcium levels and serum inorganic phosphorus levels. Bone mineral density was determined at the distal 1/3 and 1/6 of the radius on the nonshunt side. As a result, the required amount of oral phosphate binder was increased; however, there was no need to significantly increase the amount of activated vitamin D. Intact parathyroid hormone showed no significant variation, but the highly sensitive parathyroid hormone was significantly increased. There were no significant changes in any bone metabolic markers or in bone mineral density. From these study results, it was found that it was difficult to increase the dose of activated vitamin D even if low-calcium hemodialysate was used, and that during use of the low-calcium hemodialysate the serum level of parathyroid hormone tended to increase but led to neither acceleration of bone turnover nor a decrease in bone mineral density.

Changes in trough levels of whole blood cyclosporine and graft function of a kidney transplant recipient with onset of hypothyroidism after transplantation

The immunosuppressive and toxic effects of cyclosporine (CsA) are affected by many factors. We present the first case of a kidney transplant patient who had an onset of hypothyroidism about two months after the transplantation. In this case, trough levels of whole blood CsA and total serum cholesterol levels increased at the same time. But the decrease in renal function was not as severe as expected from the very high trough levels of whole blood CsA. Elevation of the trough level of whole blood CsA may be due to a decrease in CsA clearance resulting from the decreased cytochrome P-450 activity in hypothyroidism. Furthermore, a decrease in thyroid hormone level and increase in plasma lipoprotein level might have affected the distribution of CsA, and this change might have influenced the toxic effect of CsA In conclusion, our case suggests that thyroid function and plasma lipoprotein level should be considered important factors that affect the pharmacokinetics and action of CsA.