[Recurrent synovial chondromatosis of the tarsometatarsal joint. Case report and review of literature]

Primary synovial chondromatosis is a rare and usually monoarticular metaplasia of the synovia. It may recur, but the tendency to malignant transformation is very low. The radiological and histopathological differentiation from low grade chondrosarcoma can be difficult. We present a case report of a 32-year-old male with synovial chondromatosis in the tarsometatarsal joint area, which is an uncommon localization.

[Computer-assisted surgical planning. 3-D software for the PC]

A potent software was developed for virtual planning in orthopedic surgery with complex spatial relationships, that runs on a standard PC with Windows 98/NT/2000. This voxel-based 3D-software creates data from tomographic images (CT, MRI, 3D-Sono, PET) in Dicom-III-format, that are visualized in near real-time as 2D-reconstructions or 3D-images. For three-dimensional analysis interactive tools, geometric rulers and an anatomic coordinate-system are available. Multiplanar osteotomies are carried out with a virtual saw. Selected segments are moved freely to mimic fracture reduction and deformity correction. Three-dimensional movement coordination is supported by problem-oriented movement features and a 3D-mouse. User defined objects in CAD-format like implants or anatomical templates can be inserted and moved. Matching of two volume data sets is possible as well as simultaneous processing of different data sets. All 3D-reconstructions can be calculated as virtual radiographs and viewed stereoscopically with LCD-shutter glasses. Export features in various data formats allow further processing of all volume data in CAD applications and rapid prototyping. An intra-operative navigation system can be integrated via an interface. This universally applicable software allows thorough three-dimensional analysis and processing of volume data sets from tomographic images and can be used in various applications through its flexible modular setup.

[Injuries of the pelvic girdle. The pathway to exact diagnosis: which imaging methods are indicated? Synopsis of information]

Synopsis in diagnosis of pelvic ring fractures begins with the help of our senses while taking the history, inspecting and palpating the patient. It is continued with urological, gynecological and neurological assessment of the whole extent of peripelvineal injury. The picture is completed by ultrasonography, standard X-rays and special views, two- and three-dimensional CT and finally MRI. To minimize radiation damage to the patient and to lower the costs for radiologic assessment the standard ap view of the pelvis has to be analysed carefully to avoid numerous special views. Horizontal lines drawn perpendicular to the L5-Sacrum-Symphysis axis are helpful in discriminating rotational and translational instability, quantifying the extent of dislocation and controlling the quality of reduction and internal fixation. In order to avoid missing fractures of the os sacrum, the arcuate lines have to be inspected carefully.

[Distal radius fracture--is non-bridging articular external fixator a therapeutic alternative? A prospective randomized study]

A randomised prospective study was carried out to compare non-bridging external fixation using a small A0 external fixator with percutaneous Kirschner wire fixation and plaster in the treatment of distal radial fractures (A2/A3 in the A0 classification). The study involved 40 patients, 20 in each group. The advantages of the non-bridging fixation are: (1) early functional therapy of the wrist, (2) simplified reduction of the fracture, and (3) considerable less restriction of wrist mobility in day-to-day situations. Although the final examination 6 months after treatment showed almost identical functional results, the patients treated with the external fixator benefited from the fact that use of the wrist was virtually free throughout the entire treatment period.

[Injuries of the tibialis posterior tendon: diagnosis and therapy]

Complete traumatic rupture of the tibialis posterior tendon is absolutely rare. From the scarce case reports in the medical literature a extreme pronation-abduction or pronation-external rotation mechanism according to the Lauge-Hansen classification can be presumed, leading to a malleolar fracture because of forced pronation, external rotation and dorsiflexion of the foot. With primary suture the prognosis is favorable. Traumatic dislocations, mostly with luxatio pedis sub talo, are treated by atraumatic reduction and refixation of the retinaculum. Again, the prognosis is favorable. Incomplete traumatic rupture of the tibialis posterior tendon with development of posttraumatic pes plano valgus, according to case reports and our own experience result from severe pronation-external rotation-soft tissue injuries as well as with pronation-abduction or pronation-external rotation-type ankle fractures. In these cases no macroscopic rupture of the tendon is evident, however occult interstitial micro-ruptures can occur because of excessive stretching, which can be determined histologically. If conservative measures fail, a modified Evans osteotomy to lengthen the lateral foot column is indicated. Degenerative complete and incomplete ruptures of the tibialis posterior tendon are predominantly seen in women more than 42 years old. Staging of this entity can be achieved with clinical tests (muscular force, external rotation), ultrasound, weight-bearing x-rays, CT and MRT. According to the degree of decompensation of tendon function, treatment consists of augmentation, modified Evans procedure or triple arthrodesis of the hind-foot.

[Fatal aorto-esophageal fistula as a late complication of traumatic aortic rupture]

We report on a case of a 23 years old man who was polytraumatized in a car accident. He survived with excellent clinical outcome, but 113 days after the accident he collapsed, massive bleeding out of the mouth started and the patient died within a few minutes. A gastric ulcer bleeding was assumed, but autopsy showed the break-in of a posttraumatic aortic aneurysm into the esophagus. The difficulties of in time diagnosis of thoracic aorta lesions are discussed.

[Lisfranc arthrodesis after malunited fracture healing]

The causes of residual deformity with posttraumatic painful arthritis after tarsometatarsal (Lisfranc) fracture-dislocation with the need for correctional arthrodesis are in our experience (22 cases over 5 years) overseen injuries in one third, closed reduction and immobilisation or inadequate fixation technique with K-wires in another two thirds of cases. Foot malalignment and residual instability is assessed with weight-bearing radiographs of both feet, adduction/abduction stress films and CT scans for complex deformity. Correction is carried out via two longitudinal dorsal incisions, strict epiperiosteal preparation and debridement of the Lisfranc joint of all remaining cartilage, sclerosis and fibrous tissue. Reorientation begins, in the same manner as primary open reduction, with anatomical alignment of the second metatarsal base to the second cuneiform. Defects are filled with autologous bone grafting, stable fusion can be achieved with 3.5 mm cancellous compression screws. Full weight bearing is allowed in a modelled plaster shoe for 6 to 8 weeks. The functional medium-term results are convincing with 15 of 17 patients seen after 13 months of follow-up working full time. The Maryland Foot Score improved from 38.9 to 76.8 points in these patients.

[Arthrodesis - non-union of the ankle. Arthrodesis failed]

Non-unions after fracture dislocation of the ankle joint are extremely rare with predominantly operative treatment. In contrast, after fractures of the tibial plafond (pilon fractures) infections are seen in the literature in 37 % and non-unions are seen in 27 % after open reduction and internal fixation, requiring secondary ankle arthrodesis in about one quarter of all cases. In contrast to aseptic non-union or arthrosis, which can be salvaged with screw arthrodesis, with prevailing infection and severe osteoporosis external fixation (either one- or two-sided) is the treatment of choice. In isolated non-unions of the malleoli, either plate osteosynthesis with 3.5 low-contact dynamic compression plate or tension banding with autologous bone graft interposition, or alternatively sliding graft technique, is performed with good results.

Charcot Foot

Charcot foot in its original sense is equivalent to stage 4 of hereditary motor and sensory neuropathy (HMSN) which is known as Charcot-Marie-Tooth disease since 1886. This entity, which can be subdivided into 3 groups including subgroups, predominantly begins during childhood and progresses slowly. The first symptom, often unnoticed by the patient for a long period, is weakness of the intrinsic foot muscles with consecutive hammer-toe formation and mobile pes cavus. Progredient atrophy of the peroneal, extensor, tibialis posterior and finally triceps surae muscles leads to fixed pes cavus varus excavatus with severe varus deformity of the hindfoot, secondary varus position of the talus at the ankle level and subsequent arthrosis of the medial compartment. Permanent varus deformity of the ankle almost invariably leads to stress fractures of the malleoli because of repetitive microtrauma (stage 5 of HMSN).Early detection of the disease with nerve conduction studies at clinical suspicion allows tibialis posterior transfer, correctional osteotomy of the hindfoot or arthrodesis of Chopart's or Lisfranc's joint and can postpone or prevent the otherwise inevitable triple arthrodesis which has a less favorable long-term prognosis. At stage 4 (manifest Charcot foot) and stage 5 (neuropathic fracture of the ankle) a reorientating ankle arthrodesis is advocated, with additional subtalar pathology correctional double arthrodesis becomes necessary.In diabetic arthropathy of the ankle (Type IV according to Sanders and Frykberg), which is often referred to as "Charcot Ankle", tibiocalcanear arthrodesis is indicated. In case of supervening infection or extensive necrosis a modified Pirogoff amputation is carried out as a salvage procedure.Doubled periods of non weight-bearing, immobilization and brace protection of the ankle help to reduce the frequently observed implant failure in both forms of osteoarthropathy. In addition to stable implants retrograde calcaneotalotibial transfixation with a Steinmann pin may help to protect the achieved result despite prolonged bone consolidation.

[The Charcot joint]

Charcot foot in its original sense is equivalent to stage 4 of hereditary motor and sensory neuropathy (HMSN) which is known as Charcot-Marie-Tooth disease since 1886. This entity, which can be subdivided into 3 groups including subgroups, predominantly begins during childhood and progresses slowly. The first symptom, often unnoticed by the patient for a long period, is weakness of the intrinsic foot muscles with consecutive hammer-toe formation and mobile pes cavus. Progredient atrophy of the peroneal, extensor, tibialis posterior and finally triceps surae muscles leads to fixed pes cavus varus excavatus with severe varus deformity of the hindfoot, secondary varus position of the talus at the ankle level and subsequent arthrosis of the medial compartment. Permanent varus deformity of the ankle almost invariably leads to stress fractures of the malleoli because of repetitive microtrauma (stage 5 of HMSN). Early detection of the disease with nerve conduction studies at clinical suspicion allows tibialis posterior transfer, correctional osteotomy of the hindfoot or arthrodesis of Chopart's or Lisfranc's joint and can postpone or prevent the otherwise inevitable triple arthrodesis which has a less favorable long-term prognosis. At stage 4 (manifest Charcot foot) and stage 5 (neuropathic fracture of the ankle) a reorientating ankle arthrodesis is advocated, with additional subtalar pathology correctional double arthrodesis becomes necessary. In diabetic arthropathy of the ankle (Type IV according to Sanders and Frykberg), which is often referred to as "Charcot Ankle", tibiocalcanear arthrodesis is indicated. In case of supervening infection or extensive necrosis a modified Pirogoff amputation is carried out as a salvage procedure. Doubled periods of non weight-bearing, immobilization and brace protection of the ankle help to reduce the frequently observed implant failure in both forms of osteoarthropathy. In addition to stable implants retrograde calcaneotalotibial transfixation with a Steinmann pin may help to protect the achieved result despite prolonged bone consolidation.

[Dislocation fractures in the area of the middle foot--injuries of the Chopart and Lisfranc joint]

Dislocation fractures of the Chopart and Lisfranc joint line result from rough force and lead to articular incongruities, complex derangement of the plantar arc geometry and shortening of the medial or lateral column of the foot. These injuries are often complicated by severe soft tissue damage causing a high incidence of compartment syndrome. Beside careful clinical examination radiographs in 3 standard projections are essential for the exact diagnosis, if necessary completed by conventional tomographies or CT. To avoid residual joint incongruities and derangements of the anatomic architecture resulting in disabling arthrosis the indications for open reduction and functionally stable osteosynthesis should be broad. Concerning injuries of the Chopart joint any shortening of the medial or lateral column--especially if there is a substantial impression of the articular surface--should be reduced. Osseous defects have to be filled with autogenous cancellous bone and are stabilized with transarticular K-wires, 2.7 mm or 3.5 mm screws or small plates. Dislocation-fractures of the Lisfranc joint can be fixed by percutaneous K-wires if a closed reduction is possible. Open reduction and internal fixation are indicated in cases of instable and irresponsible fractures, and in open fractures as well as in lesions presenting with a compartment syndrome. A precise anatomic reduction of the tarsometatarsal joints is critical after this kind of injuries to avoid long-term disability.

[Complex trauma of the foot]

Following complex foot injuries (incidence up to 52%) in the multiply-injured patient the ultimate goal remains the same as for all significant foot injuries: the restoration of a painless, stable and plantigrade foot to avoid corrective procedures with moderate results. In the case of a complex trauma of the foot (5 point-score)--e.g. a crush injury--primary amputation in the multiply-injured patient (PTS 3-4) is indicated. Limb salvage (PTS 1-2) depends on the intraoperative aspect during the second look (within 24-48 hours after injury): the debridement has to be radical, the selection of amputation level should be at the most distal point compatible with tissue viability and wound healing. A free tissue transfer should be done early if necessary. Single lesions presenting with a compartment syndrome need an immediate dorsal fasciotomy, in the case of a multiply-injured patient as soon as possible. Open fractures are reduced following radical debridement and temporarily stabilized with K-wires and/or tibiotarsal transfixation with an external fixateur until the definitive ORIF. Dislocation-fractures of the talus type 3 and 4 according to Hawkins' classification need open reduction and internal fixation by screws (titan). Open fractures of the calcaneus are stabilized temporarily by a medial external fixateur after debridement until the definitive treatment. If there is a compartment syndrome an immediate dermatofasciotomy is essential. Like closed, calcanear fractures in multiply-injured patients dislocation-fractures of the Chopart's joint need immediate open reduction only if it is an open fracture or associated with a compartment syndrome. The incidence of a compartment syndrome in the case of dislocation fractures of the Lisfranc's joint is high and therefore a dorsal dermatofasciotomy without delay is critical. Open reduction and internal fixation are achieved either by 1.8 mm K-wires or 3.5 mm cortical screws. To avoid further soft tissue damage a delayed primary closure can be necessary and a temporary tibio-tarsal transfixation is useful. Despite the life-threatening injuries of the multiply-injured patient one must insist on an exact diagnosis of the foot trauma (radiographs in 3 standard projections: exact lateral, dorso-plantar, 45 degrees oblique) if long-term disability due to articular incongruities and complex derangement of the arc geometry of the foot is to be avoided.

Technique of using the AO-femoral distractor for femoral intramedullary nailing

Immediate closed interlocking intramedullary (IM) nailing of femoral shaft fractures in polytraumatized patients using the fracture table may be difficult due to concomitant adjacent injury. We report on the technique of using the AO-femoral distractor for femoral IM nailing and our experience with 56 consecutive cases of IM nailing of the femur. The AO distractor is an alternative to the traction table. Unlike the latter, it does not rely on intact adjacent structures to distract the main fragments. Schanz screws are placed into the femur condyle and into the lesser trochanter. The fracture is distracted and reduced by manipulating the mobile elements of the device. The femur is aligned and stabilized while reaming and nailing commence. Between April 1988 and June 1992, 56 IM nailings were performed using the AO distractor for reduction: 41 for acute unstable fractures and 15 for corrective procedures. In 11 of 15 polytraumatized patients, the fractured femurs were nailed immediately. Intraoperatively, the distractor greatly facilitated fracture reduction and presented no problems for proximal or distal interlocking. Intraoperative complications included two fracture extensions during nailing and three rotational malalignments over 15 degrees. One nonunion occurred; otherwise, all fractures were considered healed within 16 weeks. No postoperative nerve palsies were recorded, and no infection occurred. Based on our experience, we believe that the AO distractor is a suitable alternative to the traction table as a distraction and reduction device and can be implemented in all nailing cases. We particularly recommend its use in polytrauma cases in which concomitant injury precludes the initial use of the fracture table.