Geometrical analysis for assessing torsional alignment of humerus

BACKGROUND

Compared to other types of surgeries, minimally invasive surgeries (MISs) of humeral shaft fractures are associated with less radial nerve injury, less soft tissue injury and higher union rate. However, malrotation often occurs in MISs when closed reduction methods are used. This study aims to define specific palpable landmarks to help surgeons determine the correct torsional angle and reduce the incidence of malrotation.

METHODS

Twenty-eight normal humeral computed tomography scans were retrieved from our image database. One line was drawn through the vertices of the intertubercular sulcus of the humeral head in the coronal view, and another line was drawn through the longest axis between the medial and lateral condyles in the coronal view. The angle between these two lines was measured at least 3 times for each scan.

RESULTS

The profile of the intertubercular sulcus tangent line of the humeral head and the axis of the distal humerus was identified as the most accurate method for assessing the precision of torsion during MIS for humeral shaft fractures. The transepicondylar axis line is more internally rotated than the intertubercular sulcus tangent line. The mean angle was measured to be 41.1 degrees.

CONCLUSIONS

The axis of the distal humeral condyles is internally rotated by approximately 41.1 degrees compared with the intertubercular sulcus tangent line of the humeral head. Minimally invasive surgeries can be performed by using these palpable landmarks. The torsional deformities can be reduced with the proper angle adjustment without the need for fluoroscopy. It can also be used to treat unstable comminuted humeral fractures.

LEVEL OF EVIDENCE

Retrospective Study, Diagnostic study, Level III.

An assessment of femoral rotational alignment of mini-incision total knee arthroplasty: A comparison based on the transepicondylar line from the kneeling view and the intraoperative posterior condylar line

BACKGROUND

Rotational alignment of the distal femur is important in total knee arthroplasty. The purpose of this study is to use a roentgenographic technique to evaluate the accuracy of mini-incision total knee arthroplasty (MIS TKA) performed based on the transepicondylar line from the kneeling view.

METHODS

Totally 32 patients (aged from 64 to 80 years with an average of 70.9 years) with 46 cases of knee osteoarthritis received MIS TKA were registered. Before surgery, the condylar twist angle was measured from the kneeling view. The bone cut for the external rotation was completed, with regard to the condylar twist angle. The control group including 26 patients (aged from 50 to 89 years with an average of 69.7 years) with 42 cases of knee osteoarthritis underwent TKA with built-in cutting jig design 3 degrees of femoral external rotation. This study is a prospective continuous-time duration analysis study. The level of evidence is IIc.

RESULTS

The mean condylar twist angle was 5.1° in the experimental group and 5.4° in the control group. The mean postoperative angle between the clinical epicondylar axis and the posterior condylar line of the femoral component was 0.46°. The same postoperative angle of the built-in external rotation in the control group was 2.7°. The condylar twist angle was significantly more accurate than the built-in design.

CONCLUSION

Our result substantiates that the kneeling view is practicable and reproducible as the cutting reference for femoral external rotation. The accuracy of the kneeling view shows that the epicondylar axis can be used in smaller wound surgery, such as MIS TKA.

LEVEL OF EVIDENCE

Level IIc.

Reconstruction of nasal tip support in primary, open approach septorhinoplasty : A retrospective analysis between the tongue-in-groove technique and the columellar strut

The reconstruction of the nasal tip support is one of the most essential issues in septorhinoplasty. A comparison of the results after using the tongue-in-groove technique and the columellar strut technique was the target of this study. Thirty-three patients who underwent a primary, open approach septorhinoplasty using the above-mentioned techniques were retrospectively analyzed. The gain in tip rotation postoperatively, the sensitivity and the rigidity of the nasal tip and the aesthetic outcome after surgery were examined and evaluated. Both techniques led to an increase in nasal tip rotation postoperatively. The gain in rotation was higher in patients, treated with the tongue-in-groove technique (p = 0.0052). The sensitivity of the tip region in the tongue-in-groove group of patients was significantly lower than that in the columellar strut group of patients (p = 0.0424). Both techniques led to high percentages of tip rigidity after surgery with satisfactory aesthetic results though. The tongue-in-groove technique and the columellar strut technique are both reliable techniques for reconstructing the nasal tip support and correcting a droopy tip. Although the tongue-in-groove technique might result in a more significant increase in tip rotation, it leads to less sensitivity in the tip region.

Improved alignment and operating room efficiency with patient-specific instrumentation for TKA

BACKGROUND

Achieving accurate alignment in total knee arthroplasty (TKA) remains a concern. Patient-specific instrumentation (PSI) produced using preoperative 3D models was developed to offer surgeons a simplified, reliable, efficient and customised TKA procedure.

METHODS

In this prospective study, 60 patients underwent TKA with conventional instrumentation and 71 patients were operated on using PSI. The primary endpoint was surgical time. Secondary endpoints included operating room (OR) time, the number of instrument trays used and postoperative radiographic limb alignment.

RESULTS

Compared to conventional instrumentation, PSI significantly reduced total surgical time by 8.9 ± 3.3 min (p=0.038), OR time by 8.6 ± 4.2 min (p=0.043), and the number of instrument trays by six trays (p<0.001). Mechanical axis malalignment of the lower limb of >3° was observed in 13% of PSI patients versus 29% with conventional instrumentation (p=0.043). PSI predicted the size of the femoral and tibial components actually used in 85.9% and 78.9% of cases, respectively.

CONCLUSION

PSI improves alignment, surgical and OR time, reduces the number of instruments trays used compared to conventional instrumentation in patients undergoing TKA and results in fewer outliers in overall mechanical alignment in the coronal plane.

LEVEL OF EVIDENCE II

Prospective comparative therapeutic study.

Combined fixation with plates and transmalar Kirschner wires for zygomatic fractures

After repair of a fractured zygoma, the fixed zygoma occasionally becomes displaced. This phenomenon--generally called "relapse"--is a complication that can be prevented by fixing plural sites with plates. However, this impairs blood supply to the bone, which causes atrophy. To solve this dilemma, we developed a new concept for fixing the zygoma. Fractured zygomas are fixed by combining plate fixation at a single site with transmalar fixation with Kirschner wires. This secures stability of the fixed zygoma without impairing its blood supply. We evaluated the stability of fractured zygomas fixed by our method by doing dynamic experiments using simulation models. The stresses at the screw-bone interfaces were significantly reduced by the additional transmalar fixation with wire, indicating that zygomas fixed by our method are less likely to relapse than zygomas fixed with a single plate. We also reviewed the outcomes of patients treated by our method, which indicates its clinical usefulness.

Femoral fracture malrotation caused by freehand versus navigated distal interlocking

OBJECTIVES

Rotational deformity following intramedullary nailing of femoral shaft fractures is a clinically significant and underdiagnosed problem. Intraoperative determination of rotation is difficult and may be caused by several factors. The insertion of interlocking screws at a slightly oblique angle may cause a substantial degree of rotational deformity, and this factor has not been evaluated as a cause of malrotation.

METHODS

In eight paired cadaveric femurs, a midshaft transverse fracture was created and an antegrade nail was placed. The specimens were placed in a custom jig which allowed free rotation of the distal segment. Distal interlocking was performed using either a freehand technique or with navigation, and femoral anteversion was measured before and after interlocking to determine the change caused by the interlocking screw.

RESULTS

Freehand placement led to rotational shift up to 7 degrees (mean, 5.8 degrees ; range, 4-7 degrees ), and navigated insertion led to a change of 2.0 degrees (range, 1-3 degrees ; p<0.05). In addition, drill-nail contact and a visible shift of the fracture site occurred in all freehand trials, whereas in the navigation group, contact occurred in only one trial without fracture movement.

CONCLUSIONS

Freehand distal interlocking may be a substantial cause of rotational deformity, and the assistance of computer navigation systems may improve this malrotation.

Pleural flap to prevent lobar torsion: a novel technique

Lobar torsion is reported as very rare but sometimes catastrophic complication if overlooked during the early postoperative period following a lobectomy, though it is totally preventable. In this novel technique, a piece of parietal pleural flap is harvested from the posterior wall of the chest using a hook diathermy while keeping its upper border as close to the apex as possible. Finally, distal end of the flap is secured to the upper edge of the lobe using a fine monofilament absorbable suture. This procedure not only protects the lobe from rotation but also maintains continuous expansion of the lung in the early postoperative period and may, therefore, be a good option to prevent such a serious complication in selected patients following a lobectomy.

Indirect ultrasound measurement of humeral torsion in adolescent baseball players and non-athletic adults: reliability and significance

Accurate clinical interpretation of shoulder rotation range requires knowledge of the contribution of humeral torsion. This study compares the reliability of indirectly measuring humeral torsion using ultrasound visualisation with direct palpation and compares the degree of humeral torsion in a non-throwing adult population with a population of elite adolescent baseballers. The reliability of a novel method of indirectly measuring humeral torsion using palpation and ultrasound was established prior to using the ultrasound method to determine the amount of humeral torsion in both humeri of a group of 16 non-throwing subjects and 36 elite adolescent baseball players. Excellent inter-tester reliability was found for the ultrasound method of measuring humeral torsion in each arm (ICC 2,1: 0.98 and 0.94) but poor reliability for the direct palpation method (ICC 2,1: 0.51 and 0.49). Using the ultrasound method, side-to-side differences in humeral torsion ranged from 0 to 13 degrees for the non-throwing group and 0 to 29 degrees for the baseball players. This side-to-side difference was significant in the baseball players (p<0.001) but not significant in the non-throwing group (p=0.43). Whilst side-to-side differences in humeral torsion were noted between all subjects irrespective of arm dominance, only throwers demonstrated consistently greater humeral retrotorsion in their throwing arm. A reliable clinical tool for estimating humeral torsion, such as that employed in this study, will allow for a more valid prescription of interventions for the treatment of shoulder dysfunction.

Dance training intensity at 11-14 years is associated with femoral torsion in classical ballet dancers

OBJECTIVE

To examine in a cross sectional study the influence of femoral torsion (FT) and passive hip external rotation (PER) on turnout (TO). Starting age, years of classical ballet training, and current and past dance training intensity were assessed to determine their influence on FT, PER, and TO in pre-professional female dancers.

METHODS

Sixty four dancers (mean (SD) age 18.16 (1.80) years) were recruited from four different dance training programmes. They completed a dance history questionnaire. FT was measured using a clinical method. PER was measured with the subjects prone, and TO was measured with the subjects standing.

RESULTS

Mean TO was 136 degrees, mean unilateral PER was 49.4 degrees, and mean FT was 18.4 degrees. A positive correlation was observed between PER combined (PERC) and TO (r = 0.443, p < 0.001). A negative association was found between FT combined (FTC) and PERC (r = -0.402, p = 0.001). No association was found between starting age or years of classical ballet training and FTC, PERC, or TO. Dancers who trained for six hours a week or more during the 11-14 year age range had less FT than those who trained less (mean difference 6 degrees, 95% confidence interval 1.4 to 10.3). Students currently training for longer had higher levels of TO (p < 0.001) but comparable PERC and FTC.

CONCLUSION

FT is significantly associated with PERC. Dancers who trained for six hours a week or more at 11-14 years of age had significantly less FT. FTC had a significant influence on PERC, but no influence on the execution of TO.

[Antenatal diagnosis and postnatal management of ovarian cysts]

INTRODUCTION

Advances in perinatal sonography have brought to light the problem of ovarian cysts in the fetus and their management during pregnancy and after birth. The majority of such cysts disappear during infancy. According to most researchers, surgery is required when cyst diameter exceeds 5 cm. Complex cysts and complicated cysts also require surgical intervention.

AIM

To present an analysis of the diagnostic and surgical approach to ovarian cysts disclosed antenatally or during the first months of life and managed at the Department of Pediatric and Oncological Surgery, Pomeranian Medical University in Szczecin.

MATERIAL AND METHODS

A retrospective study was done in 11 newborns/infants treated for an ovarian cyst in 1998-2004, including 5 with antenatal diagnosis of ovarian cyst. Circumstances and time when the decision to operate was made were studied in the context of eventual complications and risk of loss of ovary.

RESULTS

The decision to operate in 10 newborns/infants (one cyst with a diameter of 1.86cm disappeared spontaneously in the fifth month of life) was made when cyst diameter was 4cm or greater or when the cyst was smaller but revealed mobility and sonographic signs of a complex cyst or torsion (5 cases). The diameter of cysts disclosed perinatally ranged from 2.5 to 7 cm (one of them was a chocolate cyst). The ovary was spared in eight patients.

CONCLUSIONS

Early sonographic monitoring should be undertaken in newborns with perinatal diagnosis of ovarian cyst. Because of the risk of torsion (50% of cases in the present study), surgical intervention is necessary when cyst diameter is 4 cm or greater.

[Etiology of torsio uteri in cattle: a review]

An overview about various observed phenomena, assumptions, and relations concerning the development of uterine torsion in cattle is presented. Furthermore, contradictory observations and old ideas are relativated and more accurate interpretations are given. It is known that the fetus himself is moving what is considered a reason for a torsion of the uterus. Intrauterine movements of the fetus are physiologic, and therefore other factors for uterine torsions are likely to be involved. A very plausible explanation for the selective occurrence of uterine torsion in cattle seems to be decreased amniotic fluid in relation to the size of fetus and uterus, because other influences can also be observed in all or at least in a high number of other animals. Destabilizing factors concerning the uterus (tonus decreased, uterus outside bursa supraomentalis) increase the possibility of developing a torsio uteri but are not compelling for the torsio uteri.

Biomechanical analysis of the rigid fixation of zygoma fractures: an experimental study

In this experimental study, the goal was to test the sufficiency of actual fixation plates in zygomatic complex fractures and the efficiency of a modified plate at the zygomaticofrontal suture in a suitable model, which was designed for biomechanical study. To address this issue, a zygomatic fracture model produced by using a cadaveric cranium was simulated and the fractures were fixed by the actual and modified fixation materials. The force simulating masseter muscle pull was applied with the Lloyd material testing apparatus, and the rotation of the zygoma was determined using displacement transducers. In this study, there were three different experimental groups. Although miniplates at the zygomaticomaxillary buttress and microplates at the infraorbital rim were used in all three groups, three different plates (miniplate, microplate, and modified plate) were used at the frontozygomatic suture in these groups. Rotational displacement of the zygoma with the effects of simulated masseter muscle force was determined. According to the results obtained, microplates are not effective in stabilizing the frontozygomatic suture when the masseter muscle forces are within physiological range. Although miniplates stabilize zygomatic complex fractures, it was shown that modified microplates, which have no ondulation along the plate border, have a higher resistance to rotation than that of the conventional plates. The rotation angle at the instant of fracture with microplates was 4.59 degrees, and that with miniplates was 1.26 degrees. The maximum rotation angle with modified microplates was 0.32 degrees. Modified microplates designed for the fixation of fractures in the zygomatico-orbital region have been shown to be suitable in a well-designed experimental model and might be appropriate for clinical use.

Effect of torsion on microvenous anastomotic patency in a rat model and early thrombolytic phenomenon

Torsion at the microanastomosis site is a basic fault and should be avoided. In this study, we investigate the effects of different degrees of microvenous torsion on patency and its physical changes on anastomoses in a rat model. One hundred anastomoses were performed at different degrees of torsion, using femoral veins of Sprague-Dawley rats. Anastomoses were performed at 0 degrees, 45 degrees, 90 degrees, 135 degrees, and 180 degrees of torsion randomly. Patency tests immediately, 1 h, and 1 week after the anastomoses were checked, using the refill test. Measurements of external diameter were recorded at three points: one at the anastomosis site, and the others 2 mm proximal and distal to the anastomotic site. Finally, histopathologic and scanning electron microscopy studies were performed. Subsequently, because of the peculiar phenomenon of early recannulation of the thrombosed vessels, 20 vessels were also explored on the first and the third days postoperatively. The data demonstrate that torsion at 180 degrees, compared with 0 degrees, 45 degrees, and 90 degrees, impaired patency significantly (P < 0.005). In the subsequent study of 20 veins that were thrombosed on the first day, all became patent on the third day and remained so. In conclusion, rotation of a microvenous anastomosis begins to affect the patency rate at 90 degrees of torsion, and at 180 degrees has a patency rate of only 25%. However, all become patent again from the third day onwards. Thrombosis of rat femoral veins without chronic obstruction results in rapid lysis of thrombus and transient proliferative changes.

Contributions of proximal and distal moments to axial tibial rotation during walking and running

The purpose of this study was to determine the cause and effect relationship between tibial internal rotation and pronation of the foot during walking and heel-toe running. This would allow predictions of orthotic effectiveness in reducing knee pain related to excessive internal tibial rotation. Kinematic and force plate data were collected from twenty subjects performing ten running and ten walking trials across a force plate. Using a least-squares algorithm, attitude matrices for each segment in each frame were obtained and the angular velocity vector of the tibia was calculated. The intersegmental moment at the ankle was calculated from ground reaction force and kinematic data, and the power flow from foot to tibia associated with axial tibial rotation was calculated. In walking, all subjects exhibited a clear power flow from tibia to foot during most of the stance phase, indicating that the foot was following the body. This suggests that the use of foot orthoses to reduce knee pain associated with tibial rotation during walking will not be successful. During running, power flow was also mainly proximal to distal, but there were brief periods of opposite power flow. There was more variability between subjects during running, with five subjects having large distal to proximal power flow peaks. These observations may explain and support previous work that has found variable clinical effects of orthoses between patients.

The role of fluoroscopy in avoiding rotational deformity of treated femoral shaft fractures: an anatomical and clinical study

In the first part of the study we examined the accuracy of femoral anteversion (AV) determined by fluoroscopy, simulating a method used in closed intramedullary femoral nailing. Twenty cadaveric femora were used. The condyles and posterior trochanteric area were resting on a horizontal table. The proximal femur was imaged using a C-arm image intensifier with horizontal X-ray beam at an angle of 30, 45, or 60 degrees to the long axis of the femoral shaft. To evaluate the reliability of the measurements, the real AV angle was determined by radiography. A small difference (mean 2 degrees ) was found between the real AV angle and the angle between the horizontal plane and the central head-neck axis (NH angle) as displayed by the image intensifier. In a separate clinical study, the NH angle was assessed and used as a guide to intraoperative rotational reduction in ten patients with femoral shaft fracture using the aforementioned method. Follow-up examinations of the AV angle showed that rotational deformities of clinical significance were avoided.

Absorbable mesh envelope facilitates handling of pediatric en bloc kidneys during transplantation

There is increasing evidence to favor the use of pediatric en bloc kidneys in renal transplantation. However, from a technical standpoint, pediatric en bloc renal transplantation is more complex because of difficulty in optimal intraoperative handling and positioning, as well as a higher potential for vascular complications. We describe our experience with a technique that has helped us to minimize the technical difficulties associated with the surgical procedure. Use of a tailored absorbable mesh envelope improves handling of the en bloc pediatric kidneys during performance of the vascular anastomoses and reduces the risk of torsion of renal pedicles.

Early complications. Cardiac complications

Cardiopulmonary complications developing after pneumonectomy are described. Arrhythmias are seen in about 25% of patients undergoing pneumonectomy, and supraventricular tachyarrhythmias are common. To date, the efficacy of medical prophylaxis has not yet been defined. Postpneumonectomy heart failure shares a common cause with postpneumonectomy edema. Cardiac herniation with subsequent torsion is a rare but fatal complication after pneumonectomy. Early recognition and prophylaxis are always crucial.

Fetal ovarian cyst decompression to prevent torsion

BACKGROUND/PURPOSE

Neonates who have ovarian torsion caused by an ovarian cyst often lose their ovary because the torsion and infarction occurred antenatally. Because ultrasound scan has been so effective in diagnosing ovarian cysts in utero, we have a better understanding of their natural history and can select appropriate cases for cyst decompression in utero to prevent torsion. The authors reviewed experience with seven fetuses who had fetal ovarian cyst.

METHODS

During a 26-month period, seven patients were referred for the evaluation of fetal ovarian cyst. The mean gestational age at presentation was 31.9 +/- 3.6 weeks (+/-SD; range, 27 to 37 weeks). There was no history of maternal risk factors such as diabetes mellitus or fetal risk factors such as hyperthyroidism or placentomegally. All seven cases involved isolated unilateral cysts without associated anomalies or chromosomal abnormalities. Mean initial cyst diameter was 3.4 +/- 1.7 cm (+/-SD; range, 1 to 6.1). Indications used for ovarian cyst decompression included anechoic cysts with a diameter > or =4 cm, a cyst "wandering" about the abdomen on serial sonograms, or demonstrating rapid enlargement (>1 cm/wk).

RESULTS

All but one cyst progressed in size during observation. One fetal ovarian cyst (diameter, 2 cm) subsequently regressed spontaneously and another (diameter, 2.1 cm) stabilized during prenatal ultrasound surveillance. One "cyst" observed with a diameter of 3.5 cm proved to be a persistent cloaca. Four fetal ovarian cysts met criteria for decompression. Because of fetal position, decompression could not be performed in one. One cyst (seen before defining criteria for decompression) with a diameter of 5 cm was observed only and underwent torsion. Two cysts (diameters, 6.1 cm and 4 cm) were decompressed in utero under local anesthesia with ultrasound guidance, of 95 mL and 35 mL, respectively. High cyst fluid progesterone (12,041 and 1,990 ng/dL, respectively) and testosterone (1,298 and 2,900 ng/dL, respectively) confirmed the etiology of the cyst as ovarian. Neither cyst recurred, and postnatal ultrasound scan confirmed resolution. There was no maternal or fetal morbidity or mortality and only the patient observed before development of criteria for decompression lost her ovary because of torsion.

CONCLUSIONS

Fetal ovarian cysts tend to present as isolated unilateral lesions in normal fetuses in the third trimester. Spontaneous regression of fetal ovarian cysts may occur. Fetal ovarian cyst decompression, in select cases, may preserve ovaries at risk for torsion.

[The rectosigmoid pouch. The Mainz pouch II. Apropos of 73 cases]

The Mainz Pouch II, a low pressure rectosigmoid réservoir for urine is created without any bowel anastomosis. Antimesenteric opening of the intestine at the rectosigmoid junction and subsequent wide-to-side anastomosis are performed. Without the risque of damaging the mesentery blood supply, the pouch is fixed at the area of the pomontory or the psoas muscle to avoid the kinking of the ureteres and consecutive dilatation of the upper tract.

Asynchronous ovarian torsion--the case for prophylactic oophoropexy

The case of an 11 year old girl who suffered torsion of the left ovary 8 months following right oophorectomy for a similar event is presented. The left ovary was saved by immediate surgical intervention. The value of prophylactic oophoropexy in unilateral ovarian torsion is discussed.

Distal in situ vein bypass torsion--a technique to avoid it

One of the stated advantages of the in situ bypass is that twists or torsion along the vein are automatically prevented by the technique. Unfortunately, this is not strictly true because the distal mobilized end of the vein, which is being anastomosed to the outflow tract, is quite prone to twists of 180 to 360 degrees after its arterialization. This torsion may result in either immediate cessation of flow or later formation of an anastomotic stenosis. We describe a technique that, when used, should eliminate all such problems.