Promontory of radius: a new anatomical description on the distal radius

Surgical treatment of distal radius fractures with palmar plates has gained popularity as the preferred approach to achieve anatomical fracture reposition. One hundred and thirty four radii of human cadavers were examined to elucidate the anatomy of the distal radius, especially the transition of the anterior into the lateral surface and a new term was given: promontory of radius. The promontory was located on the lateral surface between the changing of the convex to the concave curvature and the base of the styloid process. The anterior surface increased gradually from the ulnar notch to the lateral surface and formed the "base" of the promontory. The length of the promontory on the lateral surface measured 14-28 mm (mean 20.766 mm, SD 2.69 mm). The width of the promontory was found in between 10 and 27 mm (mean 13.857 mm, SD 2.14 mm). The width of the distal radius was 16-38 mm (mean 31.015 mm, SD 3.26 mm) and did not show any statistical correlation to the promontory. On the anterior surface the minimal width of promontory measured 4.9 mm, the maximal one 17.9 mm (mean 8.95 mm, SD 3.60). The height of the promontory on the anterior surface ranged in between 1.2 and 4.3 mm (mean 2.90 mm, SD 1.05 mm). The promontory of radius must be kept in mind to avoid any dorsal dislocation of the radial fragment often described as complication of intraarticular fractures. Based on this anatomical survey the data can be used for a new palmar radius plate designs.     

微创克氏针置入并外固定架修复桡骨远端不稳定骨骺骨折

背景：单纯使用克氏针或外固定架治疗桡骨远端骨骺骨折的临床实践中,仍存在桡骨短缩、骨折移位等固定后并发症,尤其在不稳定骨骺骨折情况下。克氏针主要治疗桡骨远端骨折,对其骨骺骨折使用相对较少。 目的：观察外固定支架结合经皮克氏针复位固定微创治疗桡骨远端不稳定性骨骺骨折的临床效果。 方法：对90例桡骨远端骨骺骨折患儿行固定治疗,在不切开情况下微创闭合复位骨折骨骺,随机分成2组,对照组采用单纯跨腕关节外固定支架固定方案;观察组采用跨腕关节外固定支架结合经皮克氏针闭合帮助复位固定骨骺骨折方案。固定后行腕关节功能锻炼,分别于固定后9周及24个月随访观察。对比两组患者固定后中远期的临床疗效、腕关节功能恢复及X射线检查情况。 结果与结论：固定后24个月随访按Cooney标准评定腕关节功能,对照组优良率77%,X射线评定优良率63%;观察组腕关节功能优良率93%,X射线评定优良率为90%,两组差异具有显著性意义(P < 0.01)。两组骨骺骨折患者均获临床骨愈合,腕关节均功能恢复。提示外固定支架结合克氏针闭合复位微创治疗桡骨远端不稳定骨骺骨折,可应用克氏针辅助复位掌倾角及尺偏角,治疗简单,固定可靠,腕关节功能恢复良好,骨骺畸形愈合并发症少,固定后基本生活学习功能恢复正常,疗效稳定满意,其临床疗效明显优于单纯跨外固定支架固定。     

桡骨远端不稳定性关节内骨折治疗方法的比较

目的比较外固定支架与T型钢板内固定治疗桡骨远端不稳定性关节内骨折的临床效果。方法将2007年8月~2010年1月连续48例桡骨远端不稳定性关节内骨折﹙FrykmanⅦ型、Ⅷ型﹚随机分成2组,其中外固定架组23例,男性9例,女性14例,平均年龄48.7岁﹙21~72岁﹚,右侧12例,左侧11例,按Frykman分类Ⅶ型12例,Ⅷ型11例。钢板内固定组25例,男性11例,女性14例,平均年龄50.2岁﹙20~74岁﹚,右侧12例,左侧13例,按Frykman分类Ⅶ型11例,Ⅷ型14例。分别采用闭合复位外固定架固定和切开复位T型钢板内固定治疗,Dinest标准行疗效评估。结果所有患者获得随访,随访时间12~23个月,平均16个月,X线片示所有骨折均已愈合,术后1年后复位质量和疗效2组无显著性差异﹙>0.05﹚。结论闭合复位外固定支架固定和切开复位T型钢板内固定2种方法治疗桡骨远端不稳定性关节内骨折,均可获得较满意的疗效,应根据患者具体情况选择最佳的治疗方法。     

Anatomical landmarks for locating the sphenoid ostium during endoscopic endonasal approach: a cadaveric study

Purpose

The sphenoid ostium (SO) provides a natural portal for entering the sphenoid sinus and beyond up to the skull base. It is not always easy to locate the ostium during the endoscopic approach. The present study was designed to establish readily identifiable anatomical landmarks for locating the sphenoid ostium.

Methods

Cadaveric dissection was performed in 30 hemisections of head and neck and various measurements were taken from fixed anatomical landmarks in the nasal cavity to the sphenoid ostium. The size, shape and position of sphenoid ostium were determined in relation to the anterior wall of the sphenoid sinus and the superior turbinate.

Results

The mean distance from the supero-lateral angle of the posterior choana to the SO was found to be 21.21 ± 6.02 mm. The mean distance of the SO from the midline was 4.85 ± 2.89 mm. In all the specimens, the SO was situated within 1 cm of the midline. The mean distance between the inferior end of the SO and the postero-inferior edge of the superior turbinate was 8.03 ± 3.52 mm. The SO was present on an average distance of 55.1 ± 3.54 mm from the limen nasi. In 93.3 % of the specimens, the SO was situated between 5 and 6 cm of the inferior end of the limen nasi. The angle between the anterior nasal spine and the SO was found to be remarkably constant. In 93.3 % of the specimens, it was from 25° to 30°.

Conclusions

The sphenoid ostium could be localized medial to the superior turbinate between 1.5 and 3 cm above the supero-lateral angle of the posterior choana, within 1 cm of the midline and within 1 cm of the postero-inferior edge of the superior turbinate.     

Anatomical study of the medial patello-femoral ligament: landmarks for its surgical reconstruction

Purpose

The aim of this dissection study was to describe the anatomical insertions of the medial patello-femoral ligament (MPFL), and to assess its relationship with surrounding structures to improve its surgical reconstruction.

Methods

Twelve knees (7 cadavers) were included for the study. Measurements and general features of the MPFL were assessed: lengths, widths and insertions.

Results

The MPFL was found in all knees, presenting a triangular shape, and extending from the medial part of the patella to its femoral insertion (its length was of 59 ± 6.6 mm), distal to the adductor tubercle. The mean femoral insertion of the MPFL was 7.2 ± 2.7 mm proximal and 7.4 ± 4.0 mm posterior to the medial femoral epicondyle (MFE). It was also at a mean 11 ± 2.8 mm distal and 1.3 ± 2.1 mm posterior to the adductor tubercle, and 22 ± 6.4 mm anterior to the posterior condyle. We did not find any double-bundle organization on the patellar insertion. The width of the MPFL was 8.8 ± 2.9 mm at the femoral insertion, 27 ± 5.9 mm at the patellar insertion, and 12 ± 3.1 mm in the middle of the MPFL. The vastus medialis obliquus was found to be inserted on the superior part of the MPFL.

Conclusion

The adductor tubercle appeared to be a better landmark than the MFE for the femoral tunnel positioning during surgical reconstructions of the MPFL because it was easier to identify and its relationship with the femoral insertion of the MPFL was constant (10 mm below).     

Measurement of short-term growth with a new knee height measuring device

Information on short-term growth (growth over periods of 1 month or less) has potential use in the clinic for treatment of children with growth disorders, and knowledge about patterns of short-term growth may also contribute to an understanding of growth control mechanisms. Limitations of measurement reliability for most measurements of linear growth have generally confined us to evaluation of growth over periods 3 month or longer. This report introduces the Knee Height Measuring Device (KHMD)

1 The Knee Height Measuring Device is available from Intersciences Development Associates, 3508 Market St., Philadelphia, PA 19104 (215–662–0700), patent pending.

, which can measure changes in size of the lower leg of approximately 0.5 mm and thus assist in evaluation of short-term growth. It is smaller, more portable, and less expensive than the Valk lower leg measuring device (knemometer) and uses a less subjectively biased measurement technique. Preliminary comparisons using a sample of 15 children measured twice at a 28-day interval of the validity and reliability of a prototype KHMD and the Valk knemometer. Yielded an intraobserver error of 0.295 for the KHMD and 0.206 for the knemometer. Agreement of the two instruments on the presence of detectable growth was 90%. Pearson correlation of growth rates detected by the two instruments was 0.73. After additional alterations improving the design and measurement methodology of the KHMD, 103 children 6–10 years old were measured at 28-day intervals from January to June and then at 3-month intervals from June to December of 1988 using the improved KHMD alone. Intraobserver error for these measurements was 0.22 mm. This error was modestly associated with the weight of the child (r=.31) but unrelated to sex, height, or growth in any dimension. Interobserver error for 22 children measured by two observers was 0.33 mm. We analyzed the knee height growth data primarily to test whether monthly growth could be reliably detected by this instrument. Average 28-day knee height growth was 1.76±0.3 mm, which is three times greater than the 0.5 mm growth detectable with the KHMD. Over any given 1-month interval, fewer than 10% of the children had growth less than that which could be detected with the instrument. We conclude that the KHMD can reliably detect growth over a 1-month interval and has potential clinical use for monitoring growth and for evaluating the characteristics and associations of short-term growth.     

A new method for measuring the pneumotachometer characteristics using a syringe

A new method for determining the nonlinear characteristics of pneumotachometers was developed. This method consists of a computer algorithm analyzing unsteady flows generated by a syringe. We removed the possible influence of the frequency characteristics of the measuring system by inserting an acoustic low pass filter in the path of gas flow. Two types of Fleisch pneumotachometers were tested. For a given volume of 3 l, the error of measured volume is 12.5% in uncorrected series and 0.2% in the corrected.     

Micro-light guides: a new method for measuring tissue fluorescence and reflectance.

Three-way light guides containing one or more strands of 25-micron or 80-micron diameter optical fibers in each channel have been constructed and used to measure the NADH fluorescence and UV reflectance from mitochondrial suspensions, the perfused, hemoglobin-free rat liver, and the perfused beating interventricular septum of the rabbit. The optical changes measured with these so-called micro-light guides, which have channels containing one or several strands of optical fibers less than 100 micron, are comparable in magnitude with those measured using much larger conventional light guides. The effect of light scattering on the fluorescence channel has been determined and an empirical equation for correcting the fluorescence channel for light scattering has been obtained for mitochondrial suspensions. A mathematical equation characterizing the optical behavior of a two-way micro-light guide has been derived and has been shown to account satisfactorily for reflectance and fluorescence measurements of a mat surface in air.     

Anatomical landmarks for localizing the buccal branch of the trigeminal nerve on the face

The current literature is lacking in anatomical landmarks for identifying the buccal branch of the trigeminal nerve on the face. The current study was performed to elucidate this anatomy. Forty cadaveric sides underwent dissection to measure the distances from landmarks of the superficial face to the buccal nerve in this region. On average, the buccal nerve was found to lie 3 cm lateral to the angle of the mouth and at this same level, the nerve was located a mean of 5 mm medial to the medial aspect of the masseter muscle. The buccal nerve was found to be on average 7 mm from the point of entrance of the parotid duct into the buccinator muscle and had an average distance of 5.5 mm from the facial artery. We believe that additional landmarks for identifying the buccal nerve on the face may be of use to the surgeon and dentist.     

A computer-assisted method for the study of the trabecular bone of the distal radius on conventional radiographs

The procedure described is based on the acquisition and processing of x-rays of the distal radius obtained under standard conditions. An x-ray was obtained of the forearm together with an aluminum step wedge to automatically normalize the photometric values of the bone with respect to the photometric values of the reference aluminum wedge. Densitometric values for thickness (T) and a coarseness parameter (C) that depends on the trabecular bone pattern are measured on interactively selected rows and regions of interest (ROIs) of the digital image. Twenty-five women were examined and two different measurements were performed. The first measurement considers C in three sites of the radial epiphisis. The trabecular bone coarseness appears to increase from the distal to the very-very distal site and the value of C in the very distal site, which is located 1 cm distally to the distal one tenth of the radius, seems to be related to the pathological variations more than the value of C in the other sites. The second measurement is the C/T ratio of eight ROIs of 15 patients: five healthy and 10 osteoporotic women. This ratio is significantly different for the two groups in all the eight ROIs and the variations are particularly significant at 6 to 12 mm from the subchondral line.     

A new method for measuring urinary orotic acid

A relatively simple and specific method for measuring urinary orotic acid is reported. With this method, orotic acid is enzymatically converted to uridine 5-phosphate. The difference in absorbance produced by a simple colorimetric procedure in the presence and absence of the enzymatic conversion allows specific measurement of orotic acid. Normal values for urine are less than 4 micrograms/mg creatinine in infants and less than 3 micrograms/mg creatinine in older children and adults.     

A new method for measuring daytime sleepiness: the Epworth sleepiness scale.

The development and use of a new scale, the Epworth sleepiness scale (ESS), is described. This is a simple, self-administered questionnaire which is shown to provide a measurement of the subject's general level of daytime sleepiness. One hundred and eighty adults answered the ESS, including 30 normal men and women as controls and 150 patients with a range of sleep disorders. They rated the chances that they would doze off or fall asleep when in eight different situations commonly encountered in daily life. Total ESS scores significantly distinguished normal subjects from patients in various diagnostic groups including obstructive sleep apnea syndrome, narcolepsy and idiopathic hypersomnia. ESS scores were significantly correlated with sleep latency measured during the multiple sleep latency test and during overnight polysomnography. In patients with obstructive sleep apnea syndrome ESS scores were significantly correlated with the respiratory disturbance index and the minimum SaO2 recorded overnight. ESS scores of patients who simply snored did not differ from controls.     

Anatomical studies of a boy trisomic for the distal portion of 13q

A boy trisomic for the distal portion of 13q was dissected in detail and compared to 8 cases of complete trisomy 13 previously studied in our laboratory. The comparison shows that the partial trisomy 13q case did not correspond well to a muscle phenotype based on 6 variations common trisomy 13, but rather to a larger muscle phenotype that included variations less frequently observed in complete trisomy 13. Additional cases of partial trisomy 13 must be studied before these findings can be related to specific portions of chromosome 13.     

Effects of a sliding plate on morphology of the epiphyseal plate in goat distal femur

The aim of this study was to observe the effects of a sliding plate on the morphology of the epiphyseal plate in goat distal femur. Eighteen premature female goats were divided randomly into sliding plate, regular plate and control groups. Radiographic analysis and histological staining were performed to evaluate the development of epiphyseal plate at 4 and 8 weeks after surgery. In the sliding plate group, the plate extended accordingly as the epiphyseal plate grows, and the epiphyseal morphology was kept essential normal. However, the phenomenon of the epiphyseal growth retardation and premature closure were very common in the regular plate group. In addition, the sliding plate group exhibited more normal histologic features and Safranin O staining compared to the regular plate group. Our results suggest that the sliding plate can provide reliable internal fixation of epiphyseal fracture without inhibiting epiphyseal growth.     

Evaluation of the safe zone for percutaneous Kirschner-wire placement in the distal radius: Cadaveric study

Distal radius fractures are a common injury that is often reduced with percutaneous K-wires. The sensory nerves in this area are at risk of injuring from pin placement. Cadaveric studies of the nerve distribution patterns have elucidated certain safe zones for pin placement that limits the risk of sensory nerve injury. These studies have advocated a limited open technique that involves a shallow incision followed by blunt dissection to the bone before a k-wire is drilled into the radius. A previously identified safe zone in the anatomical snuffbox was evaluated in 40 cadaver wrists for k-wire placement via a percutaneous technique that involves putting the pin directly through the skin without an incision or blunt dissection. After k-wire placement each wrist was dissected and sensory nerve distribution relative to the pin placement was evaluated. The variability of the distribution of the sensory nerves, namely the lateral antebracheal cutaneous nerve and the superficial branch of the radial nerve, is such that no truly safe zone exists for pin placement with the percutaneous technique in this area.     

Buttressing angle of the double-plating fixation of a distal radius fracture: a finite element study

Treatment of a distal radius fracture should consider principles including stable fixation and early motion. The aim of this study was to investigate the biomechanical interactions of plate-fixation angles in the internal double-plating method coupled with various load conditions using non-linear finite element analysis (FEA). A 3D finite element distal radius fracture model with three separation angles (50, 70, and 90°) between the buttressed L- and straight plates was generated based on computed tomography data. After model verification and validation, frictional (contact) elements were used to simulate the interface condition between the fixation plates and the bony surface. The stress/strain distributions and displacements at the radius end were observed under axial, bending, and torsion load conditions. The simulated results indicated that the bending and torsion increased the stress values more than the axial load. The radius and straight plate stress values decreased significantly with increasing fixation angles for all load conditions. However, the L-plate stress values increased slightly under the bending buckling effect. The displacements at the radius end and strains at the fracture healing interface decreased with increasing fixation angles for axial and torsion conditions but displayed a slight difference for the bending condition. The findings using FEA provide quantitative evidence to identify that much larger plate fixation angles could provide better mechanical strength to establish favorable stress-transmission and prevent distal fragment dislocation.