A Serial Study Of Calcaneal Fracture

Calcaneal fractures account for approximately 2% of all fractures, but approximately 75% of fractures of the tarsal bones, and Approximately 75% of calcaneal fractures are intraarticular.Because of the complexity of the joints, functional impairment, and permanent disability often arise, long-term results are often disappointing after both conservative and operative treatment. The long-term results of treatment are to a large extent dependent on the accuracy of the surgical reduction of the bone fragments. The most common causes of injury are falls from a height, either accidental or suicidal, and road traffic crashes. Conventional radiographs are taken mediolaterally and axially. Additional projections are seldom useful, but CT is considered the routine procedure for diagnosis.A sound understanding of the anatomy of the calcaneus is essential in determining the patterns of injury and treatment goals and options. The lateral surface is flat and subcutaneous, with a central peroneal tubercle for the attachment of the calcaneofibular ligament centrally. Medially, the talus is held to the calcaneus firmly by the interosseous ligament and the thick medial talocalcaneal ligaments. The sustentaculum tali is seen at the anterior aspect of the medial surface. The groove inferior to it transmits the flexor hallucis longus tendon. The neurovascular bundle runs adjacent to the medial border of the calcaneus. The neurovascular bundle may be injured during trauma or during surgery by the reduction of the sustentacular fragment, which is a key element in the surgical management of calcaneal fractures.The first classification was introduced by Bohler, and Essex-Lopresti developed a classification the basic principles of which are still used. These authors differentiated intra-articular and extra-articular fractures, and the two distinct entities, the joint-depression, and the tongue-type fractures.Since the introduction of sequential CT, various suggestions have been made for classifying calcaneal fractures. The precise assessment of fracture fragments by CT scan provides a considerable advantage for modern classification schemes. The most widely used classification system is that of Sanders et al. This system bases its classification on the number of fracture fragments that is identified on a semicoronal CT image. The image used is the one that displays the widest undersurface of the posterior facet of the talus. Sanders et al. described the talus as being divided into three columns by two lines. Theses lines divided the posterior articular facet into three potential pieces: a medial, a central, and a lateral fragment. The lines are lettered according to placement on the facet. Lateral fracture lines are type A, central lines are type B, and medial lines are type C. The addition of a third line that is located just medial to the medial edge makes for a fourth possible fracture piece, the sustentaculum portion. All nondisplaced fractures(regardless of the number of fracture lines) are classified as typeⅠ; one fracture lines is a typeⅡ; two fracture lines is a typeⅢ; and three or more fracture lines is a typeⅣ. this system has been useful in terms of determining treatment, and was shown to correlate well with prognosis and level of operative difficulty.The treatment of displaced calcaneus fractures has generated controversy throughout the past 150 years. Although both diagnostic and therapeutic tools have been improved dramatically over the recent two decades, many aspects of the management of these injuries continue to be topics for debate. The irregular anatomy of the calcaneus, the complicated coupling with the talus and tarsus via three joint facets and the highly specialised, delicate soft tissue envelope have made operative treatment a challenging task to the fracture surgeon.Assessment and treatment of these injuries has improved significantly over the past 2decades with the use of CT scanning. It has allowed us greater understanding of the pathologic anatomy of these fractures, and has provided us with a prognostic classification system with respect to outcome. Treatment options can be broken down into the following categories: emergent, nonoperativel, minimally invasive ORIF, standare open reduction with internal fixation, and primary arthrodesis.Nonoperative treatment is effective for fractures that are nondisplaced or minimally displaced(<2mm). ORIF is the standard therapy for fractures that are displaced greater than 2mm.The management of intra-articular calcaneal fractures remains controversial. Nonoperative treatment options include elevation, ice, early mobilization, and cyclic compression of the plantar arch. Conservative treatment of displaced calcaneus fractures frequently leads to severe functional impairment with considerable disability.To avoid the feared soft tissue complications, several minimally-invasive and percutaneous approaches have been proposed throughout the history of calcaneal fracture treatment and recently gained popularity for selected injury patterns .Operative treatment options include closed reduction and percutaneous pin fixation, open reduction and internal fixation, and arthrodesis. The effect of operative versus nonoperative treatment has been the focus of several comparative studies.The primary goals of open reduction and internal fixation in the treatment of displaced intra-articular calcaneus fractures are: 1) re-establishment of the normal anatomy of the posterior facet; 2) narrowing of the width of the calcaneus to prevent lateral impingement of the peroneal tendons and the sural nerve; and 3) re-establishment of normal height of the calcaneus. These goals should be achieved with the shortest surgical time to reduce the risk of infection and wound complications. Sufficient rigidity should be established to allow for early motion of the ankle and subtalar joints. Patients who have severely comminuted fractures(Sanders typeⅣ)can be treat with an ORIF of the body of the calcaneus combined with primary subtalar arthrodesis.The management of calcaneus fractures and their associated soft tissue injuries are challenging tasks for the surgeon. Open reduction and stable internal fixation with a lateral plate and without joint transfixation has been established as a standard therapy for displaced intra-articular fractures with good to excellent results in two-thirds to three-quarters of cases in larger clinical series. Bone grafting appears not useful in the vast majority of cases. Anatomical reduction of joint congruity and the overall shape of the calcaneus are important prognostic factors. The extended lateral approach respects the neurovascular supply to the heel and allows a good exposure of the fractured lateral wall, and the subtalar and calcaneocuboid joints in most fractures. In selected fracture patterns percutaneous screw fixation, possibly with arthroscopic control, is a good alternative. The quality of joint reduction should be reliably proven intra-operatively either with Brode′n views, highresolution fluoroscopy or open subtalar arthroscopy. Treatment results are adversely affected by open fractures, delayed reduction after more than 14 days and individual risk factors such as high body mass index and smoking. Open fractures, compartment syndrome and fractures with severe soft tissue compromise are treated as emergency cases. Early, stable soft tissue coverage appears promising in treating complex open fractures.Calcaneal malunions after conservative therapy of displaced fractures are disabling conditions that can be treated successfully with a staged protocol according to the type of deformity. Treatment options include lateral wall decompression, subtalar in situ, or corrective, arthrodesis and calcaneal osteotomy along the former fracture line.Comparison of the various treatment methods is hampered by the lack of a uniform fracture classification and outcome measurement. A well-accepted fact is, however, that the sequelae of calcaneus fractures have a considerable socio-economic impact since a great percentage of these injuries occur in young and middleaged male industrial workers.The treatment of calcaneus fractures has to be tailored not only to the individual fracture pattern and soft tissue damage but also to the functional demand, comorbidities and compliance of the patient.Although surgical stabilization of calcaneus fractures can produce excellent results, the reported rate of wound complications can be puite high. The development of major wound complications is a serious concern in treating calcaneal fractures. The soft-tissue envelope around the calcaneus is particularly thin and vulnerable over the lateral wall, which is exposed for surgery in most cases. The hazard with the medial approaches lies in the nearby neurovascular bundle. After open reduction and internal plate fixation of displaced calcaneal fractures, wound edge necrosis is seen in 0.4—14% with the extended lateral approach . With combined medial and lateral approaches, the rate of wound edge necroses reaches 27%. Infection rates after using the extended lateral approach vary between 1.3% and 7%. After Folk et al reported on 25% of wound complications in a cohort of 190 patients, with 21% requiring further surgery。Several smaller direct approaches to the lateral calcaneal wall, resembling the classical Palmer approach, have been carried out without significantly reducing the soft-tissue problems as they cut through the angiosome of the lateral calcaneal artery. A direct approach over the sinus tarsi requiring retraction of the peroneal tendons and sural nerve with minimal internal fixation resulted in an infection rate of 8.5% and further 9.2% soft-tissue problems like peroneal tendinitis, sinus tarsi syndrome, and even compartment syndrome.The present study demonstrates that wound complications are high in certain patient groups. Smoking, diabetes, and open fractures all increase the risk of a significant wound complication.Part oneA serial anatomic study of calcaneal一.The Clinical Significance of Anatomical of Calcaneus and Iit's Three-dimension and Multiplanar Reconstruction With Sprial CT MeasurementObjective: To provide the anatomical date experience for the internal fixtion of calcaneal fracture with self-made calcaneal anatomic plate and screw.Methods:An anatomic study was carried out on 40 adult dry calcaneal specimens by the measurement of anatomical of calcaneus and it's three一dimension and multiplanar reconstruction with sprial CT.Results: The whole length of calcaneus was72.88±4.19mm;The longth between calcaneal tubercle and sulcus calcaneus was 54.99±3.61mm; The height and width in posterior part of calcaneus were 40.80±2.84mm;30.13±2.93mm; Highest of calcaneus was 45.10±2.89mm; The height and width in anterior part of calcaneus were 22.08±2.33mm;25.10±2.64mm respectively . The length,width and height of sustentacdum tali were 23.12±1.88mm;15.68±1.55mm;10.15±1.16mm respectively. There is no difference between various indexes of anatomical of calcaneus and it's three- dimension and multiplanar reconstruction with sprial CT measurement.and there is no difference between various indexes of ours and before reports .Conclusions: The results of measurement of our play an important role in the the design of self-made new calcaneal anatomic plate and screw for internal fixtion of calcaneal fracture .二.The establishment of calcaneal morphous database for health adult crowdObjective:The criticality of treatment of calcaneal fracture is to recovery calcaneal outline ,the paratopic relationship of talocalcaneal joint and the loading model of calcaneus.The half-lateral calcaneal fracture can be regained according to the anatomic data of uninjuried-side calcaneus.There was no local reference data to patients of bilataral calcaneal factures and was difficult to judge the nomal size of calcaneus accutly in operation.Thereby it is necessary to build the database of the relationship of calcaneus and stature.Method: Select 200 adult men and 200 adult women in north according to the randomization principle(average age of men 38.9y;avrage age of women 36.2y),who are free from diseases of bone and joint by medical examination.Mesure all the body height of subjects and scan their calcaneus by 64-layer spiral CT.Images were 3D or 2D reconstructed by the way of Multiplanar reconstructions and Surface shaded display.The cutting techniqiue was used to cut the 3D images in any plane so that to show the shape and size of calcaneus at the best angle and direction.Thereby measure the height,width and the width of sustantaculum tali accurately and get anatomic datas.Finally we try to set up linear regression equation of calcaneal anatomic data and the stature.Results:The shape and structrue of calcaneus is complicated whose cortex is thin and cancelloeus bone is much. Bone trabecula is rare in the anterior of calcaneus and intensive in the posterior.The normal data between left and right calcaneus is no significant difference.However,there are significant difference among each index except Gissanecs'angle between male and female. The ratio of body height and width of calcaneus is more than 1/2. The whole length of calcaneus was72.88±4.19mm;The longth between calcaneal tubercle and sulcus calcaneus was 54.99±3.61mm; The height and width in posterior part of calcaneus were 40.80±2.84mm;30.13±2.93mm; Highest of calcaneus was 45.10±2.89mm; The height and width in anterior part of calcaneus were 22.08±2.33mm;25.10±2.64mm respectively . The length,width and height of sustentacdum tali were 23.12±1.88mm ; 15.68±1.55mm ; 10.15±1.16mm respectively.Conclusion:we set up the database of normal people according to the measured data and manufacture many sorts of new type of anatomic calcaneal plate and breakdown-easily screw which is adapt to operation with improved microinvasive small incision.Before operation we measured patients'normal feet and select the size,longth and width of internal fixation equipment and different length of screws in different sites of calcaneus.三.External Fixation of the Calcaneus: An Anatomical Study for Safe Plate placement and Pin InsertionObjective: to investigate areas in the hindfoot where external fixation pins could be safely inserted with the least risk to underlying nerves, vessels, and tendons.Methods: Sixteen fresh adult amputated feet were dissected .Using palpable anatomic landmarks, two relative"safe zones"on the calcaneus were delineated. These included an area on the medial calcaneus, the lateral calcaneus .Results: The medial calcaneal safe zone was a large, easily definable rectangular area on the posterior aspect of the tuberosity, posterior to the neurovascular bundle and extrinsic tendons. The lateral calcaneal safe zone consisted of a large area of the lateral calcaneal tuberosity, located posterior to the peroneal tendons and sural nerve trunk.Conclusions: The data presented here provide information to assist selection of pin sites that minimize risk to underlying soft tissues during external fixation of the calcaneus.四.The application and clinical significance of the imageology of peroneal tendon sheath in calcaneal fractureObjective:To explain the cause of the pain of calcaneal outer flank caused by calcaneus broadening after calcaneal fracture through the imaging verification of the phenomenon of the oppression of fibular tendon .Methods: The peroneal tendon sheath imaging were carried on 15 patients of calcaneal fracture associated with talocalcaneal joint surface and 15 patients of calcaneal oboslete fracture left with lateral calcaneal pain between May 2006 and November 2006.The patients are composed of 23 men and 7 women.Their age range from 21 to 46 years with average year 37.18 left feet and 12 feet were involved and ecch one is half fracture. Bilateral visulasition of peroneal tendon sheath were carried out at the same time following with ankle posterioanterior radiograph,calcaneal lateral radiograph and calcaneal axial radiograph with DR.Then they were measured on 2-dimensional CT and obersed on the 3-dimensional CT graph compared with opposite normal calcneus.Results: All 30 patients have varying degrees of the calcaneal widening and the oppression of peroneal tendon sheath phenomenon.Conclusion: The broadening of calcaneus after calcaneal fracture and the oppression of fibular tendon are the cause of calcaneus lateral pain. The calcaneus of all 30 patients become wider and sheaths are compessed to different degree.When the involved calcaneus are wider less than 3mm than normal calcaneus,the medium can flow through;When the involved calcaneus are wider more than 3mm ,the medium can't come through and the peroneal tendon sheath shows up compressed .Compared with normal calcanues the patients suffer from lateral calcaneal pain when the involved calcaneus are wider more than 3mm.Conclusion:The pain of lateral calcaneus is caused by compression of sheath of resulted from widen calcaneus after fracture.Part twoThe Design , Mechanics Annlysis and Biomechanical Evaluation of Ourself Designed Reduction and Fixation System for Calcaneal FractureObjective: To introduce the composion and mechanism of reduction of the calcaneal fracture internal fixation system, to evaluate its stability by mechanics analysis and biomechanical investigation.Methods: The calcaneal fracture internal fixation system is made of stainless steel composing of anatomic plate, reduction rod, and stud bolt. Sixteen amputated fresh adult feet and sixty patient were used in this investigation. Axial compressive load of 500N,700N was provided by biomechanic machine.Results: Mechanics analysis note that the calcaneal fracture internal fixation system is a stable system, and the stud bolt is important part of this system which can reducted the wildth of the calcaneal.Conclusions: The calcaneal fracture fixation system is a stable system. The stud bolt is the key point of this device.Part threeA Comparison of Ourself Designed Plate and AO Plate in a Calcaneal Fracture Model and Clinical applicationObjective: To compared different plates in an experimental calcaneal fracture model under biocompatible loading and clinical application. Methods:Two plates were tested:ourself designed plate and AO plate. Syntheticcalcanel(sawbone)were osteotomized to create a fracture model, and the plates were fixed onto them. Eight specimins for each plate model were subjected to loading and load to failure. Motion, forces, plastic deformation of the lpate, and comsequent depression of the posterior joint facet were analyzed.Results: During loading, ourself designed plate showed statistically significant lower displacement in the primary loading direction than the AO plate.Mean values(mm)of maximal displacements for each plate during loading were as follows:Conclusions: Our results showed that ourself designed plate provided greater stability during loading than the AO plate.Part fourCompression fixation with small incision steel plate and stud bolt for calcaneal fracturesObjective To explore the effect of surgical operation on intraarticular fracture of calcaneus by new method.Methods: From February 2005 feet in 150 patients with calcaneal fracture were treated differently based on the results of X-ray and coronal CT scan performed before and after the treatment, with micro-invasive technique, small incision(2~3 cm)was made at lateral of calcaneus, self-made calcaneal anatomical plate and screw were used. based on the results of X-ray and coronal CT scan ,According to Sanders classification system,there were 18 cases of typeⅡ,26 cases of typeⅢand10 cases of typeⅣ.Results:The internal fixation with the calcaneal anatomical plate almost restored the height,length ,width,angle of Bohler and Gissane of the calcaneus for the 150 patients. No one infection of incision happened. The results were validated using Maryland Foot Score . 183 fractures were followed up for 6-24 monihs(average,16monihs)after treatment . Excellent results were noted in 87 (47.54%)fractures,good in 80(43.72%),and fair in 16(8.74%).Conclusion : The open-reduction with micro-invasive and internal fixation with our self-made calcaneal anatomical plate and screw is one of the best ways for treatment of fracture of calcaneus.Part fivePreoperative and Postoperative Evaluation of Intra-articular Fractures of the Calcaneus Based on Sprial CT ScanningObjective: To define the relationship between postoperative congruency of the posterior facet of the subtalar joint based on Sprial CT and clinical results.Methods: Twenty-nine displaced fractures in twenty-five patients. All patients were treated with open reduction and internal fixation without bone graft. Preoperative and postoperative CT scans were taken prospectively and analyzed. Postoperative CT findings were classified into three groups, according to the degree of displacement: anatomic, no displacement; nearly anatomic, displaced less than two millimeters; and approximate, displaced more than two millimeters.Results: The reduction state after operative treatment for the cases with more comminution showed worse results when analyzed in both preoperative and postoperative CT scans. 35 of 54 fractures (64.81 percent) with anatomic reduction and 13of 54 fractures (24.07percent) with nearly anatomic reduction had excellent or good clinical results. In contrast, no fracture with an approximate reduction had an excellent result.Conclusion: An excellent or good clinical result can be expected when the postoperative displacement of the posterior facet of the subtalar joint is less than two millimeters.