Objective:To explore the radiological damage to cells induced by the delayed particles of 9C-ions for heavy ion therapy, as well as the microdosimetric distribution and biological effects of these particles on a single model of V79 Chinese hamster lung cells. Methods:The Monte Carlo program was employed to simulate the endonuclear absorbed doses of α particles with various energies (3-10 MeV) transported in cells (cell radius RC = 10 μm, nucleus radius RN = 5 μm). Then, the result were compared with the S values ( SN←N, SN←Cy, and SN←CS) derived using the medical internal radiation dose (MIRD) method to demonstrate the feasibility of Monte Carlo simulations. Finally, the energy deposition of the delayed particles of 9C-ions generated at three sites (i.e., on the surface and in the cytoplasm and nucleus of the V79 cell model) during their transport in targets was simulated, and the result ing cell surviving fraction was analyzed. Results:Monte Carlo and MIRD method yielded differences in S values of 1.91%-4.95% for SN←N (nucleus to nucleus), 1.48%-5.11% for SN←Cy (cytoplasm to nucleus), and -1.99% to 0.80% for SN←CS(surface to nucleus), indicating highly consistent S values derived using both method(differences < 6%). When a 9C-ion decayed on the surface of the V79 cell model and the produced secondary particles entered the cell, the average endonuclear absorbed dose was 10 -2 Gy orders of magnitude, with a cell surviving fraction of about 88%. In the case where decay occurred in the cytoplasm, the cell surviving fraction was about 80%. However, when the 9C ion decayed in the nucleus, α particles had short ranges and deposited most of their energy in the cell (mean endonuclear absorbed dose: 0.1 Gy). In this case, severe cell damage was induced, with the cell surviving fraction reducing to about 53%. Conclusions:9C-ions emit secondary charged particles due to decay, among which α particles cause great damage to cells when entering the nucleus and trigger evident biological effects.

Fracture mapping, also known as mapping of fracture lines, is a technique of drawing fracture lines based on 3D reconstruction of radiological images. Fracture mapping can be used to describe fracture morphology, calculate fracture line angle and fragment area, improve clinical practice, propose a new classification system, clarify a fracture mechanism, and establish a model of bone fracture. At present, fracture mapping has become a powerful tool for study of morphology and clinical decision in orthopaedics. Reviewing the development of fracture mapping techniques, this paper addresses their clinical application in knee injuries, tibial plateau fracture, distal femur fracture and patellar fracture in particular. In addition, considering the trend of fracture mapping techniques and the morphology-related studies at present, we offer suggestions concerning improvement of techniques and morphology studies in knee injuries.

Objective:To report the surgical techniques and clinical outcomes of multi-dimensional fixation of patellar multi-fragmentary fractures with locking plates.Methods:A retrospective study was performed in the 26 patients with patellar multi-fragmentary fracture who had undergone open reduction and 3-D internal fixation with locking plates from November 2016 to July 2020 at Department of Orthopaedic Surgery, The Sixth People's Hospital Affiliated to Shanghai Jiao Tong University. There were 17 males and 9 females, with an average age of 62.6 years (from 31 to 90 years). The patellar fractures were exposed and reduced via the longitudinal anterior midline incision of the knee. After the reduction was initially maintained with a cerclage wire, a trimmed and pre-contoured 3.5 mm locking plate was applied onto the patellar surface. After-wards, locking screws were inserted from the lower pole to the upper pole of the patella, from the anterior to the posterior and from the lateral to the medial, respectively, to complete the multi-planar fixation. Follow-ups assessed the B?stman score, knee pain visual analogue scale (VAS), radiographic image and fracture healing, range of motion of the knee, and complications.Results:All the 26 patients were followed up for 12 to 56 months (average, 28 months). Crutches were used while walking until an average of 1.6 months (from 1 to 3 months) after operation in all patients. At the last follow-up, the B?stman score averaged 27.5 points (from 17 to 30 points), yielding 12 excellent, 13 good and 1 poor case with an excellent to good rate of 96.2% (25/26); the knee pain VAS averaged 1.2 points (from 0 to 5 points); the active knee flexion averaged 125° (from 100° to 150°). No breakage, loosening or displacement of the patellar plates or screws was observed during follow-up, but cerclage wire breakage occurred without any symptom in 11 cases. Four patients complained of hardware irritation, and 4 patients underwent hardware removal after fracture union.Conclusion:Multi-dimensional fixation with locking plates is a viable and safe surgical option for patellar multi-fragmentary fractures, due to its satisfactory therapeutic outcomes.

Objective:To study the effects of gantry acceleration limitations of a linear accelerator (linac) on the dosimetry of volumetric modulated arc therapy (VMAT) plans, machine efficiency, and dose verification result of VMAT plans and to explore the optimal selection of gantry motion models in the Pinnacle treatment planning system.Methods:Ten cases of nasopharyngeal carcinoma, non-small cell lung cancer, sigmoid adenocarcinoma with retroperitoneal lymph node metastasis, and invasive ductal carcinoma of the breast were each selected for this study. Then two models were set up in the Pinnacle v9.10 treatment planning system, namely the one allowing gantry acceleration and the one limiting gantry acceleration. The same field arrangement, optimized target parameters, and optimized weights of VMAT plans were adopted in the two models, in order to analyze the dosimetric variations in targets and organs at risk (OARs) and compare the differences in treatment time and gamma passing rates.Results:The treatment time of the enrolled patients under the model allowing gantry acceleration was significantly lower than that of the patients under the model limiting gantry acceleration was adopted ( t=-6.751, -0.209, -19.523, -28.999; P< 0.05) and decreased by 15.27%, 18.07%, 19.71%, and 28.75%, respectively. Meanwhile, the conformity and uniformity of target areas were affected, while there was no statistical significance in the gamma passing rates in the validation of VMAT plans ( P>0.05). For the cases of nasopharyngeal carcinoma (NPC), the maximum dose to brainstem PRV increased by 1.25%. For the cases of lung cancer, the maximum dose to the spinal cord and lung V20 increased by 1.19% and 1.21%, respectively, while lung V5 decreased by 1.21%. For the cases of sigmoid adenocarcinoma with retroperitoneal lymph node metastasis, the mean doses to bilateral kidneys, livers, small intestine, and colon all increased. For the cases of breast cancer, lung V10 on the opposite side of cancer increased by 1.66% and the mean dose to the lungs on the same side of cancer decreased by 7.45%. Conclusions:The model allowing gantry acceleration allows the treatment time to be significantly shortened and the treatment efficiency improved. Although this model had the shortcomings such as affecting the conformity and uniformity of target areas to a certain extent and increasing the doses to some OARs, clinical requirements for dosimetry were still met. Therefore, it is recommended to use the model allowing gantry acceleration in the Pinnacle planning system.

Objective To investigate the outcomes of lateral approach combined with anteromedial approach for the treatment of terrible triad of the elbow injuries.Methods Data of 23 patients with terrible triad of the elbow injuries treated at our hospital using this modified surgical technique from July 2008 to January 2011 were retrospectively analyzed.Two patients lost to follow-up leaving 21 patients (21 elbows) for evaluation.There were 17 males and 4 females with a mean age of 38.4 years (range,17-63 years).The 21 elbows were treated surgically after a mean of 4 days from the injury.According to O'Driscoll classification of coronoid fractures,there were 5 cases of type A1,12 of A2,and 4 of B2.According to Mason classification of radial head fracture,there were 2 cases of type Ⅰ,12 of Ⅱ,and 7 of Ⅲ.According to Zhong Biao classification of soft tissue injury in terrible triad of the elbow,there were 6 cases of type Ⅰ,12 of Ⅱ,and 3 of Ⅲ.Our surgical procedure included fixation or replacement of the radial head and repair of the ruptured lateral collateral ligament (LCL) through a lateral approach.Simultaneous fixation of the coronoid process and repair of the common flexor muscle and medial collateral ligament (MCL) injury were performed through an anteromedial approach.Mayo elbow performance score (MEPS) was determined for each patient at the latest clinic visit.The Broberg and Morrey classification was used for evaluating traumatic arthritis.Results The mean follow-up period was 32 months.At the latest follow-up the mean flexion-extension arc of the elbow was 126° (range,115°-135°) and the mean forearm rotation was 139°(range,125°-145°).The mean MEPS was 95 points (range,85-100 points),with 19 excellent results and 2 good results.Concentric stability was restored in all cases.Early post-operative complication occurred in one patient as a wound infection,which healed uneventfully after surgical debridement and antibiotic therapy.Late post-operative complication occurred in four patients including two cases of heterotopic ossification,1 case of radial head nonunion,and one case of ulnar nerve neuropathy,but none of them required additional surgery.Conclusion Lateral approach combined with anteromedial approach for terrible triad of the elbow provided both bony and soft-tissue stability,thereby allowing early active motion as well as functional recovery of the elbow.

Objective To discuss the treatment strategy of medial collateral ligament and combined injury in the terrible triad of elbow.Methods The data of 21 patients with terrible triad of elbow who received treatment from February 2010 to April 2012 was retrospectively analyized.There are 17 males and 4females with12 cases left and 9 right elbows.The average age of them was 37.6 years (16-57).MRI examination was performed routinely,and used as guidance of treatment strategy of medial collateral ligament and combined injury.For the patients without or with partial damage of anterior bundle of medial collateral ligament(AMCL) injury while the continuity of ligament remains complete in MRI image,exploration and repair of the medial collateral ligament is not conventional.For the patients with MRI image showing AMCL avulsion or body disruption,we routinely used antero-medial approach to explore and repair,suture-anchors were used for suture the bony avulsion of the medial collateral ligament,body disruption of ligament and combined flexor-pronator teres complex injury were also be suture repaired.None of the patients used hinged external fixator during operation.A hinged brace was applied after operation.Results All patients were followed up for an average of 12.4 months (6-26).At the last follow-up,the average range of motion of the elbow was 135.2 ±10.2 degrees,average straight limited degrees,6.7±2.2 degrees,an average of 142±11.0 degrees of flexion.Mayo elbow performance score was 92 points (85-100).17 cases were excellent and 4 were good.Complications included:a transient ulnar nerve palsy in 3 cases,heterotopic ossification in 2 cases,tardive ulnar neuritis in 1 case,no elbow residual instability,dislocation,elbow stiffness and other complications.Conclusion Anterior bundle of medial collateral ligament avulsion or body disruption should be routinely suture repaired,which is in favor of restoring elbow immediate stability favoring restore elbow immediate stability.

BACKGROUND:Ankle fracture combined with deltoid ligament injury can disorders the anatomical structure of ankle joint. Improper treatment can cause more serious complication, such as walking disorders.
OBJECTIVE:To evaluate the clinical effect of anchor repair plus open reduction internal fixation in the treatment of ankle fracture combined with deltoid ligament injury.
METHODS:Thirty-five patients with ankle fracture combined with deltoid ligament injury were selected from the Department of Orthopedics, the Sixth People’s Hospital Affiliated to Shanghai Jiao Tong University between May 2009 and January 2011, including 24 males and 11 females, and al the patients were treated with anchor repair plus open reduction internal fixation. The age of the patients was 22-61 years, averaged 35.7 years, and al the patients were closed injury without other fractures. The treatment time was 2-10 days, average 4.6 days. According to Lauge-Hansen classification, 26 patients had supination-eversion ankle fracture and nine patients had pronation-eversion. According to Danis-Weber classification, 26 patients were C type and nine patients were B type. After al the three patients were treated with anchor repair, the treatment effect of anchor repair was evaluated through assessing the improvement of clinical symptoms and signs, as wel as the imaging examination of repair and healing.
RESULTS AND CONCLUSION:Al the 35 patients were fol owed-up for 9-26 months, average 13.8 months. Al the patients got Ⅰ stage healing without complications of infection and screw loosening. Fol ow-up X-ray film showed al the 35 patients with ankle fracture achieved bone union, the healing time was 10-21 weeks, average 13.6 weeks. Modified Baird-Jackson score system showed excel ent in 11 cases, good in nine cases, average in four cases, poor in one case, and the excel ent and good rate was 85.7%. At 6 months after internal fixation, the stress X-ray film examination showed the mal eolus gap of the affect side was (3.49±0.36) mm, the mal eolus gap of the healthy side was (3.37±0.41) mm, and there was no significant difference (P>0.05). The results indicate anchor in the repair of deltoid ligament injury during the treatment of ankle fracture with open reduction internal fixation can achieve satisfactory therapeutic effect.

10.3969/j.issn.2095-4344.2013.26.016

Objective To explore clinical effect of double-tube continuous negative pressure drainage in the treatment of Morel-Lavallée leision.Methods We retrospectively analyzed the clinical data of 13 patients with Morel-Lavallée leision,which were diagnosed and treated in our hospital from May 2009 to July 2010.They were 11 women and 2 men,aged from 19 to 57 years (average,32.5 years).All patients underwent operations within 3 days after injury,except for 2 patients whose diagnosis was postponed.The operation was performed with small incision and double-tubes were placed for continuous negative pressure drainage.Double-tubes were not removed until effusion was less than 30 ml/24 hours.The heal was defined as no skin necrosis and subcutaneous hydrops at lesion site,no skin floating and sliding at palpation.Results Double-tubes were removed 4 to 12 days postoperatively (average,6.3 day).All of 13 patients were followed up for an average of 13.7 months (range,10 to 18 months).Skin necrosis occurred in 1 patient.Lesions were healed 4 to 10 weeks postoperatively(average,7.2 weeks).No deep infection or delayed hematogenous infection was found.There were no general systematic complications.Superficial infection at wound site occurred in one patient and healed after wound management.Conclusion Application of double-tube continuous negative pressure drainage is a safe,less invasive,low-cost and effective treatment for Morel-Lavallée leision.

Objective To compare the clinical results of distal clavicular anatomical plates and clavicular hook plates in treatment of distal clavicular fractures.Methods Twenty-six patients with lateral 1/3 clavicular fractures of Craig Ⅱ type Ⅱ or Ⅴ treated from August 2009 to January 2011 were enrolled in the study.Eleven patients were managed by anatomic plates,including eight patients with type Ⅱ fractures and three with type Ⅴ fractures,while the rest 15 patients were treated by clavicular hook plates,including 11 patients with type Ⅱ fractures and four with type Ⅴ fractures.General information of the two groups was comparable before operation.Shoulder function after operation was evaluated by Constant-Murley score system.Postoperative radiographic findings and complications of patients in the two groups were studied comparatively.Results The distal clavicular anatomical plate group presented a lower incidence of shoulder pain and better mobility of shoulder,as compared with the clavicular hook plate group,but there were no significant differences in incision infection and implant loosening between the two groups.According to the Constant-Murley evaluation standard,excellence rates of the distal clavicular anatomical plate group and clavicular hook plate group were 91％ and 73％,respectively.Conclusion The distal clavicular anatomical plate is conducive to decrease of incidences of shoulder pain,increase of range of motion of shoulder and reduction of complications for treatment of Craig Ⅱ type Ⅱ or Ⅴ distal clavicular fractures and hence is in favor of early functional recovery of the limbs.