Repeated intramedullary stabilization following failed telescopic nail lengthening - An appropriate treatment strategy.

Externally magnetic-controlled intramedullary telescopic nails for bone lengthening have recently gained popularity due to many advantages when compared to more traditional lengthening methods. Patients requiring lengthening often present with a clinical history of previous multiple surgeries increasing the risk for complications of further procedures. However, studies regarding the treatment of complications following implantation of these devices remain scarce in literature. Therefore, we report our experience with revision surgery after lengthening with a telescopic intramedullary lengthening nail. In 6 out of 20 cases (30%) of lower limb lengthening for leg length discrepancy revision surgery was necessary. Two revisions were necessary due to nail breakage while the other 4 cases required a secondary procedure for non-union. In all cases, revision surgery included standard intramedullary locking nailing with additional autologous bone grafting. The median interval between index and revision surgery was 11.5 months (range 2-15 months). Satisfying clinical results, the intended extend of lengthening and bony consolidation was observed in all 6 patients. We conclude that revision surgery using an intramedullary locking nail with autologous bone grafting after failed telescopic nail-based lengthening represents an useful salvage procedure in these cases.

Pitfalls in automatic limb lengthening - First results with an intramedullary lengthening device.

BACKGROUND: The treatment of leg length discrepancy and deformities has become more common over the last few decades due to newly developed implants. Lengthening using fully implantable intramedullary nails provides many advantages; however, only little data is available. Therefore, we aimed to determine: (1) safety of the implant, (2) the complication rate and (3) functional outcome after magnetic driven intramedullary bone lengthening with a telescopic implant. HYPOTHESES: Automatic bone lengthening with intramedullary nails provide good short-term outcome. PATIENTS AND METHODS: Ten patients with limb length discrepancy of lower extremity, treated with an Ellipse PRECICE® nail, were included in this retrospective follow-up study. The mean limb length discrepancy was 4.7cm (range: 2.5-7.0cm). RESULTS: In all patients, limb lengthening goals were reached within a range of ±0.5cm after a mean time of 53 days. However, in 2 patients, mechanical failures with unintended shortening were observed. In a further patient nail breakage occurred. Overall, 7 patients presented with complications during the follow-up period. DISCUSSION: The PRECICE® nail represents a new, fully implantable, magnetically driven device for limb lengthening. However, due to a high rate of complications, a close follow-up is necessary to identify early implant failures and to avoid severe adverse outcomes. LEVEL OF EVIDENCE: Retrospective follow-up study, case series, level IV.

Successful limb salvage using the two-staged technique with internal fixation after osteodistraction in an effort to treat large segmental bone defects in the lower extremity.

BACKGROUND: The reconstruction of large segmental bone defects exceeding 8 cm remains a major therapeutic challenge. Strategies to avoid amputation and thereby provide satisfactory functional outcomes have not been sufficiently evaluated. Therefore, the present study reviews the clinical and functional outcomes after limb salvage. METHODS: From 1994 to 2011, a consecutive series of 12 patients with lower-limb segmental bone loss exceeding 8 cm were reviewed. Eight patients had suffered from a third-degree open fracture, whereas four patients had undergone bone resection after osteomyelitis. All patients underwent initial skeletal fixation with a simple, external frame. In six patients, the bone healed with no further stabilization after osteodistraction, while internal fixation by intramedullary nailing or plating was necessary in six patients. RESULTS: In reference to the clinical outcome, ten patients returned to their pre-injury activity level despite sustaining a total of 25 complications. Overall, patients with external fixator alone were at higher risk of sequelae (P = 0.014). In comparing the two groups, axis deviation at the lengthening site occurred in three patients without additional internal fixation; the only refracture occurred in this group. Generally, the size of the bone defect after debridement averaged 12.5 cm (range 8-26 cm). The mean distraction period until frame removal was 11 months (range 3.2-16.2 months). The EFI averaged 33.4 days/cm, whereas no significant differences in EFI were found between the groups. CONCLUSION: We observed a reduced incidence of axial deviation and refracture in patients with large segmental bone defects who underwent an additional internal stabilization after fixation with an external frame. The two-stage technique caused no increase in infectious complications and might therefore be a preferable approach for successful limb salvage in patients suffering from large segmental bone defects exceeding 8 cm with insufficient bone formation during external fixation.

Distal femoral fracture through the screw hole of a ligament augmentation device fixation.

SUMMARY: Complications associated with fixation of artificial ligaments in augmented repair of the anterior cruciate ligament (ACL) have been reported throughout the literature. However, fractures following ligament augmentation device (LAD) fixation appear to be rare. We report the case of a 43-year-old woman, injured in a road accident, who sustained a depressed fracture of the tibial plateau and knee instability. The fracture was reduced and the medial collateral ligament and the menisci were sutured. The torn ACL was repaired using the Marshall technique and augmented with an LAD in an over-the-top technique. Twenty-five months postoperatively, the patient sustained a distal femoral fracture through the screw hole of the former LAD fixation after a simple fall on the street.

Implant failure of the gamma nail.

The gamma nail is a temporary implant characterised by a limited life expectancy under continuous dynamic stress. We reviewed a series of 839 patients with gamma nail stabilisation and found two fatigue fractures (0.2%) at the aperture of the distal locking holes. This complication has not been described in the literature. Metallurgic and scanning electron microscopic examinations proved that the fatigue zones occurred at the clover-leaf grooves, which is where the diameter of the gamma nail is reduced. The clover-leaf diameter is of no biomechanical use in gamma nail stabilisation. We suggested product modification of the gamma nail to produce implants with a round diameter instead of a clover-leaf shape. A modified implant is already in use at our institution.

[Conservative versus surgical therapy of perilunar dislocation and dislocation fractures]. / Konservative versus operative Therapie der perilunären Luxation und Luxationsfrakturen.

18 perilunate dislocations and fracture-dislocations were treated at the Trauma Center of the Vienna General Hospital during the period from 1992 to 1995. Only five cases were treated without surgery. 15 of these 18 patients returned for follow-up after an average of 16 months. In ten cases good results were achieved. Radiologically, eight patients were classified as good. Overall better results were seen after surgical treatment.

[Fatigue stability of locking screws for unreamed tibial intramedullary nailing]. / Ermüdungsfestigkeit von Verriegelungsbolzen für die unaufgebohrte Tibianagelung.

Unreamed nailing with solid tibial nails is an accepted method of treatment for open tibial shaft fractures up to grade III and of closed tibial fractures with severe soft tissue damage. However, fatigue failure of the distal locking bolts is a frequent complication. We report a mechanical study investigating the fatigue limit of six different types of locking bolts used in solid tibila nails (Biorigid Tibial nail/aap, UTN/ace, STN/Howmedica, TLN/Howmedica, delta R & T Tibial nail/Smith & Nephew, AO/ASIF UTN/Synthes). Our results prove a direct correlation between the bolt's diameter and mechanical properties. Further more we found that bolts with a continuing thread were weaker than bolts of the same diameter with only a short thread and an increased diameter at the nail's aperture. Our results suggest that mobilization with half of the average body weight (350N) allows osseous consolidation without fatique failure of any of the tested locking bolts. Some of the tested locking bolts may even withstand full wieght-bearing in a physiological walking cycle, but will not withstand the stress of a running cycle.

Femur fractures in patients with hip arthroplasty: indications for revision arthroplasty.

The number of periprosthetic femur fractures has increased due to the increase in the number of patients having total hip arthroplasty. In this study, we define indications for operative treatment in patients with femur fractures after hip arthroplasty. Fifty-three patients with 56 periprosthetic fractures were available for retrospective review of charts, radiographs, and physical examination; 42 fractures were treated with open reduction and internal fixation, 8 had replacement of hip prosthesis, 4 were treated with a retrograde genucephalic nail, and 2 patients were treated conservatively. The choice of treatment depended on the stability of the prosthesis and on the type and location of the fracture. Fifty-two fractures healed primarily. Three patients sustained a refracture, one an additional fracture, and two a deep infection. We recommend treatment with plate fixation for fractures without signs of prosthetic loosening. In fractures with loose implants, revision arthroplasty is required. Distal femoral fractures should be stabilized with a plate or with genucephalic nailing.

[Periprosthetic femur shaft fracture. Indications and outcome in 51 patients]. / Die periprothetische Femurschaftfraktur. Indikationen und Ergebnisse bei 51 Patienten.

Periprosthetic femoral fractures present the problem of fracture treatment and prosthetic stability. Various treatment options are recommended for managing these fractures. We treated 51 patients with 54 periprosthetic fractures between 1985 and 1995. Of these, 42 (78%) fractures were treated with a plate, eight (14%), with a revision prosthesis, two (4%), with retrograde nailing, and two (4%), conservatively due to poor medical condition. The choice of fracture management was dependent on the type and location of the fracture and on the stability of the prosthesis. A total of 50 fractures healed primarily. Complications included three cases of plate loosening, one further fracture, one deep infection, one broken bolt and one varus deformity. Four patients died in the postoperative period, an additional 19 were dead at the time of the evaluation. Fractures with a stable implant can be treated with plate fixation. Cases of a loose implant require revision. Distal fractures are stabilized with a plate or with a retrograde nail.

Dynamic external fixation for distal radius fractures.

Thirty adult patients with closed comminuted and mostly intraarticular fractures of the distal radius were treated by closed reduction and immobilization with a dynamic external wrist fixator during a 2-year period. In 13 patients with severely comminuted and unstable fractures, additional Kirschner wires were used. After 10 to 14 days of rigid fixation in neutral position, the motion element was unlocked to allow up to 30 degrees flexion. Six weeks later, the fixator was removed. The patients then were observed for an average of 24 weeks. An excellent functional outcome was seen in 6 patients (20%), a good outcome in 20 patients (67%), and a fair outcome in 4 patients (13%). Anatomically, 15 patients (50%) had an excellent result, 14 (47%) a good outcome, and 1 (3%) a fair outcome. Only minimal loss of reduction averaging 1 degree palmar tilt was seen during mobilization. There were 2 major complications: 1 deep Kirschner wire tract infection and 1 index metacarpal fracture. Minor complications such as sensory disturbances and pin tenderness were present but recovered completely after removal of the fixator. This study provides promising data and offers an alternative method in the treatment of distal radius fractures with severe comminution. In cases with postreductive unstable fragments, additional Kirschner wires should be used to allow early mobilization of the wrist.

[Lesions of lateral ligaments of ankle joint in sports.]. / Aussenbandverletzungen des oberen Sprunggelenkes im Sport.

Lesions of the lateral ankle ligaments are most common injuries in sportsmen. Expecially games of ball and racket are of highest risk. Diagnosis consists of a comprehensive clinical examination including tests of stability as well as radiographs to exclude a fracture. Key words: lateral ankle ligaments, functional treatment, ortheses, operative treatment.

Nailing versus plating in thoracic trauma: an experimental study in sheep.

In this study, femoral intramedullary pressure, fat embolization, and pulmonary response were measured during reamed and unreamed nailing and plating of femoral fractures after blunt thoracic trauma. Intramedullary peak pressures of 425 mm Hg (mean 205 mm Hg) occurred in the reamed nail group (group I) during reaming with the 9-mm reamer, while in the unreamed nail group (group II) peak values were seen during nail insertion (330 mm Hg) with a mean of 203 mm Hg. Plating never led to a pressure rise over 67 mm Hg (mean 37 mm Hg). In reamed nailing, the most intense embolism was identified under ultrasound imaging with the large awl and with the 9.0-mm reamer (mean 2.2) and in the unreamed nail group during nail insertion (mean 2.8). Minimal echoes appeared during plating. The pulmonary arterial pressure did not vary significantly postoperatively between the three groups (p < 0.08). Our findings indicate that intramedullary fracture fixation causes a higher increase of intramedullary pressure and more fat and bone marrow embolization than extramedullary ones. Nevertheless, only minimal differences in the pulmonary hemodynamic response (pulmonary arterial pressure) were noted even in the presence of thoracic trauma.

[Experimental studies of the biomechanics of scaphoid screws]. / Experimentelle Untersuchungen zur Biomechanik von Kahnbeinschrauben.

The purpose of this study was to determine the anchoring forces of four commonly used scaphoid screws in synthetic polyurethane foam. A linear relation was found between the length of the probe and the anchoring forces. The leading thread of the Herbert screw showed a anchoring force of 54 N/mm, the trailing thread 80 N/mm, and the Ulrich screw 75 N/mm. This linear relation of the shaft screws was only relevant upto a border probe length no longer that of the thread. Furthermore, it is valid for screws with continuous threads up to a probe length of 12 mm respectively. The cortical screw developed an anchoring force of 59 N/mm and the cancellous screw, 63 N/mm. With short probes of 4 and 6 mm, the trailing threads of the Herbert and Ulrich screws have the best anchoring forces, with values of 319 N/399 N and 307 N/435 N, respectively. The forces necessary for extraction of the tested scapoid bone screws placed in 8 mm polyurethane cubes were between 404 N and 527 N and were narrowly distributed. An additional conclusion of this study was that the application of screws with flat ends (Herbert and Ulrich screws) which were placed perpendicular to the dense material layer, significantly increased the anchoring forces.

Pulmonary reaction during intramedullary fracture management in traumatic shock: an experimental study.

Immediate nailing of shaft fractures in severely injured patients causes fat embolization. This method therefore is considered potentially dangerous, since fat intravasation in association with multiple trauma and subsequent endotoxemia might lead to pulmonary dysfunction. We therefore studied the pathophysiologic events of intramedullary nailing in the lungs of sheep with chronic instrumentation including lung lymph fistula. In the 7 animals in group I closed nailing of the intact tibia and femur was performed. Group II (n = 7) animals sustained hypovolemic shock and retransfusion prior to nailing, while group III (n = 11) animals were treated like those in group II and further challenged on the following two days with endotoxin. Group III was compared with group IV (n = 6), in which endotoxin was given only once without additional trauma. Nailing in group I led to a significant increase of the MPAP from 10.8 to 13.8 mm Hg postoperatively (p < 0.05), but no increase in lung permeability. Only additional hypovolemia, retransfusion and nailing as performed in groups II and III showed significant increase of the lymph flow (QI) from 4.4 mL/h to 12.4 mL/h and the protein clearance (Pclear) from 3 to 6.3. A significant difference of the pulmonary permeability between group I and II was only observed postoperatively. There was no difference in the lung response between group III and IV. This ovine study corroborates that although nailing causes a moderate increase in pulmonary pressure, it does not lead to increased lung permeability. Only additional hemorrhagic shock, even when adequately resuscitated, leads to lung disturbance postoperatively. The subsequent endotoxin challenge does not aggravate lung injury.

Intramedullary pressure changes and fat intravasation during intramedullary nailing: an experimental study in sheep.

In this study, intramedullary reaming and nailing were performed following the insertion of pressure transducers in intact tibias and femora. The femur and tibia were instrumented in 12 sheep (group I) and both tibiae in four (group II). The eight procedures of group II were monitored additionally using echocardiography to detect emboli. Intravasation of fat globules was demonstrated in the blood by the Gurd test and correlated with intramedullary pressure and with echocardiographic monitoring in group II. Medullary nailing was found to be always associated with a severe increase in intramedullary pressure, reaching an average of 1126 mm Hg (304 to 1450 mm Hg) in the tibia and of 753 mm Hg (310 to 1126 mm Hg) in the femur during the first reaming procedures. Particle or fat intravasation was greatest during nail insertion. This phenomenon did not depend on the rise in intramedullary pressure. Our findings indicate that fat and bone marrow intravasation occurs during reaming and nailing in long bones. The maximum embolization of marrow contents demonstrated by echocardiography is seen during nail insertion independent of the changes in intramedullary pressure.

[Long-term results of Russe modified scaphoid screw fixation II]. / Langzeitergebnisse der modifizierten Kahnbeinverschraubung nach Russe II.

Proximal pole scaphoid nonunion with a small necrotic proximal fragment presents therapeutical problems. Cannulated screw fixation as a modification of the Russe II procedure combines the advantages of minimal surgical exposure and trauma, preserving the blood supply of the distal fragment, and at the same time achieving rigid fixation of the autogenous bone graft. Six out of seven patients had satisfactory subjective and objective results after a mean follow-up of 12.9 years, although radiographic findings were less favorable.

[Indications for percutaneous screw fixation of scaphoid fractures]. / Indikationen der gedeckten Kahnbeinverschraubung.

A total of 198 patients with scaphoid fracture who were treated by percutaneous screw fixation were reexamined after a mean postoperative time of 82 months. Sound radiological union and clinical healing were found in 89% of the recent fractures, 81.8% of fractures with delayed or nonunion and in 42.8% with sclerotic nonunion. Based on our experience, good results can be anticipated if the fracture is anatomically reduced and the screw correctly placed. In cases of carpal collapse, sclerotic nonunion, and or a very small proximal fragment, an open fixation method should be used.

[The anatomic isthmus in the carotid triangle]. / Der anatomische Isthmus im Karotisdreieck.

In a limited number of surgically treated patients with blunt trauma to the internal carotid artery (ICA), intimal lesions were found at the intersection of the ICA with the hypoglossal nerve (CN XII). Therefore, these clinical findings were investigated in an anatomic study. In two-thirds of these cases, the congenital "anomalous" relationship of ICA and CN XII caused a strangulation phenomenon during extreme turning manoeuvres of the head and neck. On the basis of our clinical intraoperative findings, anatomic studies und reports in the literature, a further mechanism of vascular injury is suggested in this area.

Trauma involving the proximal tibial epiphysis.

Thirty injuries involving the proximal tibial epiphysis were treated during a period of 28 years. The epiphysis was displaced in 16 cases (53%). Three patients presented with peripheral ischemia on admission, and one patient with associated ipsilateral femoral fracture developed delayed thrombosis of the popliteal artery. The treatment results were satisfactory in 21 of the 27 (74%) who were reassessed according to Shelton's evaluation criteria after an average post-traumatic interval of 11.6 years. Three of the six patients with unsatisfactory outcome had a discrepancy in leg length of more than 2.5 cm after concomitant ipsilateral fracture of the femur or the tibia. One patient had a positive 3-cm anterior drawer sign, one patient had a 10 degree valgus deformity of the tibia, and one had to undergo above-knee-amputation because of delayed diagnosis of the vascular lesion.