Volume 121  ·  Issue 15  ·  2008

Minimally invasive surgery (MIS) is the trend of development in modern surgery. Its research, application and popularization in the field of orthopaedic trauma are well demonstrated in the development of current osteosynthesis. MIS implies that a surgical operation should minimize the damages to the body tissues to reduce the postoperative pain, so as to start rehabilitation exercises earlier, to facilitate functional recovery, and to improve the outcomes of the surgical treatment。

The concept of minimally invasive surgery (MIS) is thought to minimize damage and possible reactions of the surgical site and the whole body in order to achieve the same outcome as that achieved from conventional surgery。

Abstract：Background Different kinds of minimally invasive surgery (MIS) procedures have now been used in total knee arthroplasty (TKA). Compared with traditional TKA procedure with a long skin incision, clinical studies showed MIS procedures had some advantages. Quadriceps sparing (QS) procedures are the most minimally invasive MIS procedure until now. This study was aimed to find the insertion types for Chinese patients' vastus medialis and if the QS procedure had some advantages in patients' early recovery.Methods Between February 2006 and May 2007, 120 consecutive patients underwent unilateral primary TKA under general anesthesia, among whom 14 patients were lost to follow-up, the remaining 106 cases were enrolled in this study. Among the 106 cases there were 85 right knees, 21 left knees (15 men and 91 women, with a mean age of 65.1±7.4 years); osteoarthritis in 97 patients (91.5%) and rheumatoid arthritis in 9 patients (8.5%). MIS TKA was performed in 49 cases (MIS TKA group), while MIS-QS TKA in 57 cases (MIS-QS TKA group). During the operation, the type Ⅰ, Ⅱ and Ⅲ insertions of the vastus medialis for all patients were recorded. Each knee was rated post-operatively according to the Hospital of Special Surgery (HSS) scoring system. Clinical follow-up was undertaken at 1 week, 2, 6, 12 and 24 weeks. Operating time and complications were recorded.Results There was no statistically significant difference between the two groups for gender distribution, age, left or right knee incidence, pre-operative diagnosis, incidence of varus or valgus deformity. Of the 106 cases there was 1 (0.9%) case with a type Ⅰ insertion of the vastus medialis, 4 (3.8%) cases with type Ⅱ insertions, 101 (95.3%) cases with type Ⅲ insertions. The HSS scoring was significantly different between the MIS-QS TKA group and MIS TKA group within the first two weeks post operation. From 2 weeks later to 24 weeks, no significant difference was found. The average operating time was (53.3±12.4) minutes in the MIS TKA group and (64.1±15.1) minutes in the MIS-QS TKA group (P <0.001). In the MIS-QS TKA group, 1 patient had delayed healing of the partial skin incision (1.8%). No other complications were found in either group.Conclusions Although most of the Chinese patients had type Ⅲ insertions of the vastus medialis, the MIS-QS TKA procedure showed less injury to the quadriceps than the standard MIS TKA and this could contribute to the earlier recovery of the patients. But a shorter skin incision and more tension on the skin may also lead to more skin complications。

Abstract：Background Many kinds of approaches have been used for minimally invasive surgery of total hip arthroplasty (MIS-THA). However, until now when considering the balance of efficacy and associated surgical injury there is no approach widely accepted for MIS-THA. In this study, a modified anterolateral muscle sparing approach was developed to optimize MIS-THA. Methods Twenty adult cadaver specimens (40 hips) were used for anatomic research. The distance from anterior origin of the gluteus medius on the lilac crest to the anterior superior lilac spine was measured; the course of the superior gluteal nerve and the distances from the nerve to the regional anatomic landmarks were recorded. Simulated surgeries were performed in three fresh cadaver specimens to evaluate the soft tissues injury around incisions. From October 2004 to June 2006, 57 patients (57 hips) were treated with anterolateral muscle sparing minimally invasive total hip arthroplasty, of which 17 were femoral neck fractures, 9 osteoarthritis, 16 developmental dysplasia of hip (DDH) and 15 avascular necrosis (AVN). All the operations were performed by the same senior surgeon. Operation time, blood loss and drainage volume were recorded and the correlation between the local complications and the native anatomical characteristics was especially noted. All cases were followed for at least 12 months.Results The distance from the anterior origin of the gluteus medius to anterior superior lilac spine along the lilac crest was (61±4) mm (range, 55-68 mm), and the distance from inferior branch of the superior gluteal nerve to the anterior tubercle of the greater trochanter was (74±6)mm (range, 60-88 mm). In simulated surgeries, excessive distraction of tissue was found to be the main cause of the anterior border injury of the gluteus medius muscle. Of the 57 patients treated with anterolateral muscle sparing MIS-THA, the average incision length was 9 cm (range 7.5-13 cm). Blood transfusions were performed in 11 patients. During the operations, anterior border injury in deep layers of the gluteus medius was found in 9 patients. Posteromedial perforation of the prosthesis stem on the femoral side was found in 2 patients, which were revised immediately. No positive Trenderlenburg sign was found during the 12 months of follow-up.Conclusions The incision of the anterolateral muscle sparing approach should be directed from the anterior tubercle of the greater trochanter toward 6 cm posterior to the anterior superior lilac spine. The proximal part of the incision should be within 6 cm from the anterior tubercle of the greater trochanter, and it is safe to be extended distally. The anterolateral muscle sparing approach is a minimally invasive approach for total hip arthroplasty, through which the surgeon can operate on the acetabulum and femoral sides in a single incision without muscle detachment, and fluoroscopy assistance is not needed. The surgeon should pay more attention to protecting the gluteus medius from injury by distraction before femoral neck cutting and during the preparation of the femoral side。

Abstract：Background A simple, safe and effective therapeutic strategy for traumatic instability of the subaxial cervical spine, as well as its prognostic assessment, is still controversial.Methods The therapeutic options for 83 patients of traumatic instability of the subaxial cervical spine, whose average age was 35 years, were determined, according to the Allen-Ferguson classification, general health and concomitant traumatic conditions, neurological function, position of compression materials, concomitant traumatic disc herniation/damage, concomitant locked-facet dislocation, the involved numbers and position, and the patients' economic conditions. An anterior, posterior or combination approach was used to decompress and reconstruct the cervical spine. No operations with an anterior-posterior-anterior approach were performed.Results The average follow-up was three years and nine months. Distraction-flexion and compression-flexion were the most frequent injury subtypes. There were 46, 28 and 9 cases of anterior, posterior and combination operations, respectively. The average score of the Japanese Orthopaedics Association, visual analog scale and American Spinal Cord Injury Association (ASIA) motor index improved from 11.2, 7.8 and 53.5, respectively, before operation, to 15.3, 2.6 and 67.8, respectively, at final follow-up. For incomplete spinal cord injury (SCI), the average ASIA neurological function scale was improved by 1-2 levels. Patients with complete SCI had no neurological recovery, but recovery of nerve root function occurred to different extents. After surgery, radiological parameters improved to different extents. Fusion was achieved in all patients and 12 developed complications.Conclusions The best surgical strategy should be determined by the type of subaxial cervical injury, patients' general health, local pathological anatomy and neurological function。

Abstract：Background The advantages of video assisted thoracoscopic anterior correction for scoliosis are minimal invasion and relatively short-time instrumentation; however the relatively steep learning curve cannot be ignored. Small incision, thoracotomic anterior correction for idiopathic thoracic scoliosis could be another choice because of less demanding technique. We compared the outcomes of these two techniques.Methods Forty-nine patients with idiopathic right thoracic scoliosis were randomly divided into two groups. Group A was 12 girls with mean age 14.9 years, mean Cobb angle 52° and Risser signs "+++" to "++++". Ten patients received video assisted thoracoscopic anterior correction with Eclipse rectification and two with Frontier instrumentation. Group B was 4 boys and 33 girls with mean age 14.1 years, mean Cobb angle of 56° and Risser signs "++" to "++++". These patients underwent small incision, thoracotomic anterior instrumentation. The operation time, blood loss, postoperative drainage, instrumented levels, curve correction and eady loss of correction of both groups were analyzed.Results Group A had average operation time of (390+82) minutes, intraoperative blood loss of (600+155) ml, instrumented level of 7.4+1.3, postoperative drainage of (500±160) ml, correction rate of (65±16)% and loss of correction during the 18-36 month followup of (8.6±2.9)%. Group B had average operative time of (220±80) minutes, intraoperative blood loss of (320±120) ml, instrumented level of 7.8±0.9, postoperative drainage of (210±90) ml, curve correction rate of (70±12)% and loss of correction during the 18-36-month followup of (4.6±3.9)%. The curve correction rates of the two groups were not statistically significant (P〉0.05). However, the operative time, blood loss, postoperative drainage, and early loss of correction showed statistical significance (P〈0.05).Conclusion Both video assisted thoracoscopic anterior correction and small incision thoracotomic anterior correction are safe and effective in correcting the idiopathic thoracic scoliosis。

Abstract：Background The value of somatosensory evoked potentials (SEPs) in the diagnosis and prognosis of cervical spondylotic myelopathy, as well as the usefulness of monitoring intraoperative potentials in terms of safety and predictive factors were investigated.Methods Each of the 76 myelopathic patients underwent surgical intervention. According to the wave configurations of the SEPs, the cases were categorised into four groups: Type Ⅰ, Ⅱ, Ⅲ and Ⅳ. The clinical myelopathy disability was classified and the severity of neurological deficits was scored. Clinical function after surgery was evaluated. Preoperative potentials and intraoperative monitoring were categorized. The correlations between evoked potentials detection, monitoring, myelopathy disability and surgical outcome in the different groups were discussed. Results According to the configurations of the SEPs, there were 27 patients (36%) of Type Ⅰ, 30 patients (39%) of Type Ⅱ, 8 patients (11%) of Type Ⅲ, and 11 patients (14%) of Type Ⅳ. The categorised evoked potentials were shown to be significantly associated with the clinical representation of myelopathy (P 〈0.01) and the recovery rate from identifiable SEPs waves (groups A, B and C) was significantly higher than unidentifiable waves (group D, P〈0.01). A deterioration of SEPs was detected in 23 cases (30%), whereas there was no change in 40 cases (53%) and improvements in 13 cases (17%). A significant difference in recovery rates could be observed in various monitoring groups within the short-term follow-up period, while there were no obvious differences in the long-term follow-up groups. Conclusions SEP technique is a valuable and practical tool for the diagnosis, monitoring and prognosis of myelopathy. Classified evoked potentials are well correlated with cervical spondyiotic myelopathy disability, and unidentifiable SEPs waves in patients are indicative of a relatively poor outcome. In addition, intraoperative monitoring of SEPs plays an important role in protecting neural structures during cervical spine surgery。

Abstract：Background Recently, the new generation of metal-on-metal total hip resurfacing arthroplasty is well known for preserving the proximal femoral bone stock, minimizing the risk of postoperative dislocation using large femoral heads, and expecting low wear of metal-on-metal articulation for longer prosthesis survival. It also has the advantage in biomechanical loading in the proximal femur. The osteoarthritis secondary to developmental dysplasia of the hip (DDH) has been the most common reason for total hip arthroplasty. Most of the patients are young and active, who require improved range of motion of the hip besides relief of the pain, even expect to resume the ability to run and jump after the joint arthroplasty, thus to be allowed an active lifestyle. The objective of the current study was to evaluate the early outcome of resurfacing arthroplasty for the mild DDH cases (Crowe type Ⅰ and Ⅱ).Methods Between September 2005 and May 2007, twenty-one consecutive patients (twenty-six hips) with the diagnosis of osteoarthritis secondary to DDH underwent metal-on-metal resurfacing arthroplasty. The average age at the time of surgery was 46.5 years (range, 37-59 years). Six patients (28.6%) were male and fifteen (71.4%) were female. Clinical and radiographic results were observed. The follow-up was performed at 6 weeks, 3, 6, 9 months and then yearly.Results All patients were followed for a mean of 18 months (9-29 months). During the follow-up period no complications, such as dislocation of hip joints, infection or femoral neck fracture occurred. The clinical outcomes, as rated with the Harris hip score, improved significantly compared with the preoperative ratings. The mean postoperative Harris hip score was 90.7, compared to 35.5 preoperatively. The radiographic analysis showed that all prostheses were fixed with no radiolucencies. All of the patients who had equal limb lengths preoperatively had equal lengths postoperatively. Of the nine patients with preoperative limb-length discrepancy of 0.8 to 1.2 cm, all regained equal limb length postoperatively. In addition the pain was nearly completely relieved, the range of motion was remarkably improved and no restriction was needed after operation regarding early exercise.Conclusions The new generation of metal-on-metal resurfacing arthroplasty may be a reasonable option for DDH of the Crowe types Ⅰ and Ⅱ。

Abstract：Background Thoracoscopy is highly sensitive and accurate for detecting pleural effusions. However, most respiratory physicians are not familiar with the use of the more common rigid thoracoscope or the flexible bronchoscope, which is difficult to manipulate within the pleural cavity. The semi-rigid thoracoscope combines the best features of the flexible and rigid instruments. Since the practice with this instrument is limited in China, the diagnostic utility of semi-rigid thoracoscopy (namely medical thoracoscopy) under local anesthesia for undiagnosed exudative pleural effusions was evaluated.Methods In 50 patients with undiagnosed pleural effusions who were studied retrospectively, 23 received routine examinations between July 2004 and June 2005 and the rest 27 patients underwent medical thoracoscopy during July 2005 and June 2006. Routine examinations of the pleural effusions involved biochemistry and cytology, sputum cytology, and thoracentesis. The difference in diagnostic sensitivity, costs related to pleural fluid examination and complications were compared directly between the two groups.Results Medical thoracoscopy revealed tuberculous pleurisy in 6 patients, adenocarcinoma in 7, squamous-cell carcinoma in 2, metastatic carcinoma in 3, mesothelioma in 2, non-Hodgkin's lymphoma in 1, and others in 4. Only 2 patients could not get definite diagnoses. Diagnostic efficiency of medical thoracoscopy was 93% (25/27). Only 21% patients were diagnosed after routine examinations, including parapneumonic effusion in 2 patients, lung cancer in 2 and undetermined metastatic malignancy in 1. Twelve patients with tuberculous pleurisy were suspected by routine examination. Costs related to pleural effusion testing showed no difference between the two groups (P=0.114). Twenty-three patients in the routine examination group underwent 97 times of thoracentesis. Two pleural infection patients and 2 pneumothorax patients were identified and received antibiotic treatment and drainage. Medical thoracoscopy could be well tolerated by all the patients. The semi-rigid thoracoscope could be casily controlled by chest physicians. The most common complication was transient chest pain (20 of 27 patients) from the indwelling chest tube, which would be managed with conventional analgesics. One case of subcutaneous emphysema and 2 cases of postoperative fever were self-limiting. No severe complications occurred.Conclusions Medical thoracoscopy is a simple, safe, and cost-effective tool, with a high positive rate. Physicians should extend its access to proper patients if the facilities for medical thoracoscopy are available。

Abstract：Background Transfacet pedicle screws provide another alternative for standard pedicle screw placement for plate fixation in the Iumbar spine. However, few studies looking at transfacet pedicle screw fixation in the cervical spine are available. Therefore, cervical transfacet pedicle screw fixation and standard pedicle screw fixation techniques were biomechanically compared in this study.Methods Ten fresh human cadaveric cervical spines were harvested. On one side, transfacet pedicle screws were placed at the C3-4, C5-6, and C7-T1 levels. On the other side, pedicle screws were placed at the C3, C5, and C7 levels. The screw insertion technique at each level was randomized for right or left. The starting point for the transfacet pedicle screw insertion was located at the midpoint of the inferolateral quadrant of the lateral mass and the direction of the screw was about 50° caudally in the sagittal plane and about 45° toward the midline in the axial plane. Screws were placed from the inferior articular process, across the facet complex and the pedicle into the body of the caudal vertebra. The entry point for the pedicle screw was located at the midpoint of the superolateral quadrant of the lateral mass, and the direction of the screw was about 45° toward the midline in the axial plane and toward the upper third of the vertebral body in the sagittal plane. After screw placement we performed axial pullout testing.Results All the cervical transfacet pedicle screws and the pedicle screws were inserted successfully. The mean pullout strength for the transfacet pedicle screws was 694 N, while for the pedicle screws 670 N (P=-0.013). In all but six instances (10%), the pedicle screw pullout values exceeded the values for the transfacet pedicle screws; this occurred three times at the C3/C4 level, twice at the C5/C6 level and once at the C7/T1 level. The greatest pullout strength difference at a single level was observed at the C5/C6 level, with a mean difference of 38 N (t=-1.557, P=-0.154). The C7/T1 level had a mean difference of 26 N and the C3/C4 level had a mean difference of 14 N.Conclusions Cervical transfacet pedicle screws exhibited higher pullout strength than pedicle screws. Posterior transfacet pedicle screw fixation in the cervical spine may afford an alternative to standard screw placement for plate fixation and cervical stabilization。

Abstract：Background Ginsenosides are main components extracted from ginseng, and ginsenoside Rg3 is one of the most important parts. Ginsenoside Rg3 has been found to inhibit several kinds of tumor growth and metastasis. The present study was undertaken to investigate the effect of ginsenoside Rg3 on human ovarian cancer metastasis and the possible mechanism.Methods The experimental lung metastasis models of ovarian cancer SKOV-3 and the assay of tumor-induced angiogenesis were used to observe the inhibitory effects of Rg3 on tumor metastasis and angiogenesis. The effect of Rg3 on invasive ability of SKOV-3 cells in vitro was detected by Boyden chamber, and immunofluorescence staining was used to recognize the expression of matrix metalloproteinase 9 (MMP-9) in SKOV-3 cells.Results In the experimental lung metastasis models of ovarian cancer, the number of tumor colonies in the lung and vessels oriented toward the tumor mass in each ginsenoside Rg3 group, was lower than that of control group. The invasive ability and MMP-9 expression of SKOV-3 cells decreased significantly after treatment with ginsenoside Rg3.Conclusions Ginsenoside Rg3 can significantly inhibit the metastasis of ovarian cancer. The inhibitory effect is partially due to inhibition of tumor-induced angiogenesis and decrease of invasive ability and MMP-9 expression of SKOV-3 cells。

Abstract：Background For cardiovascular tissue engineering, acellularized biomaterials from pig have been widely investigated. Our purpose was to study mechanical properties and biocompatibility of decellularized aorta of fetal pigs (DAFP) to determine its potential as scaffold for small diameter tissue engineered vascular graft.Methods Descending aorta of fetal pigs was removed cells using trypsin, ribonuclease and desoxyribonuclease. Mechanical properties of DAFP were evaluated by tensile stress-strain and burst pressure analysis. Assessment of cell adhesion and compatibility was conducted by seeding porcine aortic endothelial cells. To evaluate biocompatibility in vivo, DAFP was implanted subcutaneously into adult male Sprague Dawley rats for 2, 4 and 8 weeks.Results Histochemistry and scanning electron microscopy examination of DAFP revealed well-preserved extracellular matrix proteins and porous three-dimensional structures. Compared with fresh aorta, DAFP had similar ultimate tensile strength, axial compliance and burst pressure. Cell culture studies in vitro showed that porcine aortic endothelial cells adhered and proliferated on the surfaces of DAFP with excellent cell viability. Subdermal implantation demonstrated that the DAFP did not show almost any immunological reaction and exhibited minimal calcification during the whole follow-up period.Conclusion The DAFP has the potential to serve as scaffolds for small diameter tissue engineered vascular graft。

Despite the continual evolution in the surgical treatment of adolescent idiopathic scoliosis (AIS), the goals of surgery remain to correct and stabilize the deformity in three dimensions, to maintain equilibrium of the shoulders and trunk, and to leave as many mobile spinal segments as possible。

The arthroscope was first introduced to orthopaedics as a diagnostic instrument by Tagaki in 1918. A high degree of clinical accuracy, combined with low morbidity, has encouraged the use of arthroscopy to assist in diagnosis, to determine prognosis and often to provide treatment。

Protein tyrosine phosphorylation is a major posttranslational modification used by cells to regulate signal transduction and essentially participate in every aspect of cellular physiologic and pathogenic processes。

Hypospadias is one of the most common abnormalities of the external male genitalia but is very difficult to repair. Hypospadias reoperation is also a common practice for pediatric urologists, though repair of hypospadias at reoperation is much more difficult。

Chyluria is a disease that may severely debilitate a patient's health condition. Some investigations have indicated that in patients with chyluria, part of the uptake fat and protein leaks from the urine.1'2 Thus, recurrent chyluria may result in malnutrition。

Seasonal influenza is a highly contagious, acute respiratory illness that affects people of all ages. The major pathogens, influenza A viruses, are classified into serologically defined antigenic subtypes of the hemagglutinin (HA) and neuraminidase (NA). Of 16 identified HA and 9 NA subtypes, only H1N1 and H3N2 subtypes are now circulating among humans。

Aortic dissection and aortic aneurysm are two of the most common catastrophic events involving the aorta. Thoracic endovascular aortic repair is now considered as a promising alternative to open surgical graft replacement, The aim of endovascular repair of a thoracic aneurysm is to exclude, and thus depressurize, the aneurismal wall and the aim of the endovascular repair of type B aortic dissection is to obliterate all of the false lumen through thrombosis after sealing the primary entry tears, thus to ensure the true lumen perfusion。

Traumatic carotid-cavernous fistula (CCF) is an abnormal passageway between the intracavemous carotid artery and the cavernous sinus after a head injury. Most CCFs have direct high flow. Clinical presentations primarily depend on the pressure inside the cavernous sinus and on the direction of the venous drainage。

Multilevel aortic disease presents a formidable challenge for vascular surgeons. In the past, multilevel aortic surgery was performed simultaneously or subsequently. Single-stage intervention is thought to be associated with a high incidence of complications, and sequential repair requires several major surgical interventions。

Massive calcification of left atrium is an uncommon complication of long-standing rheumatic valvular disease, and is most often observed in patients with a previous operation on mitral valve.1 Most patients have experienced symptoms for more than 15 years.2 Massive calcification of the left atrium generally spared the interatrial septum in the previous studies.4 However, to our knowledge, fewer than five cases have presented as full left atrial calcification (Table)。

Adefinitive diagnosis of paradoxical embolism is based on the evidence that a thrombus crosses through the right-to-left shunting. We report a case of impending paradoxical embolism in a patient with pulmonary embolism diagnosed by echocardiography and proved by operation later。

An abundant chromosomal protein that binds to damaged DNA prevents cancer development by enhancing DNA repair, researchers at University of Texas reported on-line in the Proceedings of the National Academies of Science。

Lack of sexual knowledge is the main culprit for HIV/AIDS among Latin American youths, said Chilean expert Raquel Child, who also blamed the authorities for not doing enough to help youngsters deal with the deadly disease。