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PubMed1989

The effect of alignment of the implant on fractures of the patella after condylar total knee arthroplasty.

The results in thirty-six knees that had a fracture of the patella after a total condylar arthroplasty were reviewed, and were analyzed according to the type of fracture and the alignment of the implant and the limb. Most of the fractures occurred two years or less after the initial operation. Fourteen knees were rated fair or poor and twenty-two, good or excellent. None of the thirty-six implants had been aligned in the neutral range. In sixteen knees, the alignment had a minor variation from the neutral range--that is, the knees were in minor malalignment. In general, these knees had the least severe fractures and the best over-all results. All had a good or excellent result except one, which was revised because of a loose patellar component. That knee was rated as fair at the latest follow-up. There was a major discrepancy in the alignment of twenty implants. These knees had more severe fractures and less satisfactory results than those in the other group. In two of these knees, the fracture was treated non-operatively; one had a good and the other, a poor result. Twelve of the remaining knees, which were treated surgically, were rated as fair or worse. Two knees that had revision of three components and restoration of alignment to the neutral range had an excellent result. The results of this study indicate that the alignment and fit of a component are important in determining the severity of a fracture of the patella after condylar total knee replacement and the long-term results after treatment of the fracture.

Adult↗

PubMed1996

Unreamed intramedullary nailing of femoral shaft fractures: operative technique and early clinical experience with the standard locking option.

Nailing techniques have changed in recent years in ways which are not just limited to omitting the reaming process. These changes concern positioning patients, techniques of reduction and selecting implants. Techniques of approach and exposure have been modified to new, less-invasive procedures to fulfill technical, functional and cosmetic requirements. In addition, techniques have been developed to avoid fragment diastasis, rotational and sagittal malalignment, and leg-length discrepancy. Finally, simple algorithms have been elaborated for the management of specific fracture patterns (bilateral shaft fractures, ipsilateral tibial fractures or associated femoral neck fractures) and to determine the number and location of locking bolts. We developed these algorithms, techniques and procedures in a series of 133 femoral shafts, which were stabilized with the AO unreamed femoral nail (URFN) in a prospective study between 1991 and 1994. Of these, the first 57 cases with a mean follow-up of 17.9 months (range, 5-44) after injury were reviewed. Fractures were classified according to Müller's 1990 system: 12 type A, 29 type B and 16 type C. Closed soft-tissue injuries were classified by our classification of 1982: 17 type C 0/I, 42 type C II. Of 15 open fractures, six were OI, six OII, two OIIIA and one was OIIIB by Gustilo's classification of 1984. The major complications were two broken locking bolts, one nail breaking after 9 weeks, one case of osteitis and one of intra-operative lung embolism.

Adolescent↗

PubMed1999

[Surgical management of posttraumatic mal-alignments and arthroses in the ankle].

Joint incongruency, malalignement as well as degenerative changes of the ankle joint may result in disabling pain with a significant decrease in function and mobility. The clinical symptoms may affect all aspects of life. Primary osteoarthritis of the ankle joint is uncommon, and posttraumatic conditions with significant changes in joint mechanics are usually the primary source of joint degeneration with the resultant clinical symptoms. Apart from pain relief and restoration of joint mobility, prevention of joint degeneration or progression of arthrosis should be the main goal in treating such conditions. Arthrodesis of the ankle still is the method of choice for severe osteoarthritis of the ankle, however several surgical treatment options are available to deal with mild to moderate joint degeneration. Restoration of the anatomy and joint alignement in posttraumatic deformities as well as ligament reconstruction in chronic instability are measurements to prevent development or progression of osteoarthritis. Joint debridement is useful in primary anterior joint pathology, in advanced osteoarthritis at least temporary pain relief can be achieved. In severe osteoarthritis arthrodesis of the ankle is the method of choice for long-term pain relief and restoration of mobility.

Ankle Injuries↗

PubMed2005

Locked plate fixation and intramedullary nailing for proximal humerus fractures: a biomechanical evaluation.

BACKGROUND: Internal fixation of proximal humeral fractures is associated with a considerable secondary malalignment rate. Fixed-angle implants have been suggested to increase the stability of fixation. METHODS: The biomechanical properties of four different implants were tested. These included an internal fixator with semi-elastic properties (reference), the Synthes T-plate, a locked plate with rigid properties and a spiral blade locked intramedullary nail (PHN). These implants were assessed in twenty-four osteotomized pairs of human cadaveric humeri. Specimens were subjected to two-hundred cycles of axial loading and torque followed by load to failure. RESULTS: The PHN had greater axial stiffness than the reference and the T-plate. During torque, all implants were stiffer than the reference. During cyclic loading, there were no differences between the T-plate and the reference. Both the rigid internal fixator and the PHN had less irreversible deformation than the reference. Both implants resisted higher loads before failure. CONCLUSION: This study showed that the proximal humeral nail and the rigid internal fixator are stronger than the semi-elastic locked plate and the Synthes T-plate for unstable subcapital proximal humeral fractures.

Biomechanical Phenomena↗

PubMedDate not supplied

Trochanteric versus piriformis entry portal for the treatment of femoral shaft fractures.

OBJECTIVES: The purpose of this study was to compare results of femoral shaft fracture treatment with nailing through the greater trochanter to nailing through the piriformis fossa with nails specifically designed for each starting point. DESIGN: Prospective cohort study. SETTING: Four level 1 trauma centers. PATIENTS: One-hundred and eight patients treated by 1 of 4 surgeons for a femoral shaft or subtrochanteric fracture with antegrade nailing between January 2001 and April 2003 were included. Four patients who expired early in the postoperative period and 13 with insufficient follow-up were excluded from analysis. INTERVENTION: Patients were treated with either nailing through a greater trochanter starting point with the Trigen TAN nail (GT group) (n = 38) or through a piriformis fossa starting point with the Trigen FAN nail (PF group) (n = 53). OUTCOME MEASURES: Operative time, fluoroscopy time, fracture alignment, fracture healing, complications, and functional outcome based on the lower-extremity measure (LEM). RESULTS: Thirty-seven of the 38 fractures from the GT group and 52 of the 53 fractures from the PF group healed after the index procedure. One patient from the GT group had external rotation malalignment of 12 degrees. There were no other malalignments or iatrogenic fracture comminution. There were 2 infectious complications, 1 from each group. The average operative time was 75 minutes for piriformis insertion using the FAN nail and 62 minutes for trochanteric insertion using the TAN nail (P = 0.08). The average fluoroscopy time was 61% greater for the PF group (153 seconds) than for the GT group (95 seconds) (P < 0.05). These differences were magnified in patients who were obese (body mass index > 30) where the operative time was 30% greater (P < 0.05) and the fluoroscopy time was 73% higher in the PF group (P < 0.02). Patients from both groups had a similar initial decline and subsequent improvement in function over time (P > 0.05). CONCLUSIONS: A femoral nail specially designed for trochanteric insertion resulted in equally high union rates, equally low complication rates, and functional results similar to conventional antegrade femoral nailing through the piriformis fossa. The greater trochanter entry portal coupled with an appropriately designed nail represents a rational alternative for antegrade femoral nailing with the benefit of decreased fluoroscopy time and decreased operative time in patients who are obese.

Adolescent↗

PubMed1992

[Can humerus shaft fractures be treated with osteosynthesis?].

The treatment of fractures of the humerus shaft is still controversial. The results of functional treatment (brace) are good, consolidation occurs in most cases within 8-10 weeks, slight malalignment can be accepted, and there is no risk of postoperative complications like osteitis, neurological iatrogenic disorders and technical errors. On the other hand a correct osteosynthesis allows painless functional postoperative treatment, the patient comfort is excellent and a selected group of patients might return to work faster. We present the results of plate fixation of humerus shaft fractures in 127 patients, operated from 1980 to 1988. 102 patients were clinically and radiologically controlled after 1 year: 85 patients (83.4%) presented an excellent or good result with complete functional recovery. 17 patients (16.6%) showed a limited range of motion in shoulder and/or elbow mostly due to other fractures of the same arm or to persistent neurological disorders (plexus or radial lesions). Postoperative complications included 2 postoperative radial palsies recovering completely within months, 5 failures of internal fixation due to technical errors, 2 pseudarthrosis and 4 postoperative infections, healed by reoperation and early removal of the implant with one exception (osteitis). We therefore conclude, that a correct plate fixation of humerus shaft fractures is an alternative to conservative treatment. The main advantage is better patient comfort and shorter disability for a selected group of patients.

Adolescent↗

PubMed2006

Limb malalignment and functional outcome after antegrade versus retrograde intramedullary nailing in distal femoral fractures.

BACKGROUND: Torsional malalignment and mechanical axis deviation (MAD) are worrisome complications after nailing of distal femoral fractures. Variable, sometimes contradictory, reports about these problems have been published. METHODS: In a retrospective nonrandomized study, 41 patients (mean age, 44.5 years) with distal third femoral fractures that were operatively treated using either antegrade (20 cases) or retrograde (21 cases) intramedullary nailing during a period of 2 years have been reviewed. Goniometric measurement was done using a navigated ultrasound examination whereas functional evaluation and return to sports were assessed using Merle d'Aubigné functional grading system and Tegner and Lysholm activity score. RESULTS: There was no difference in femoral length, torsion, or MAD between patients treated using antegrade nails and those treated with a retrograde nail. There was a greater limitation of knee motion with retrograde nailing and of hip motion with antegrade nailing. The functional grading and activity evaluation showed, however, no difference between both groups. CONCLUSIONS: The study cohort showed that no treatment method had proved an advantage over the other regarding limb geometry or the functional outcome. The proper operative indication, intraoperative control, and the surgeon's experience seem to be more important in this regard than the nailing technique.

Adolescent↗

PubMedDate not supplied

Postnatal development of the human sternum.

Postnatal development and maturation of the human sternum are highly variable. Endochondral ossification centers (sternebrae) form within each cartilaginous segment of the sternum, with each center enveloped by a spherical growth plate. Within a cartilaginous center there may be either one or two ossification centers, those with two centers retaining and reflecting features of their bilateral embryonic origin. Malaligned bifid centers are clearly associated with rib articulation asymmetry as well. Expansion of individual ossification centers progresses within the peripheral cartilaginous domains of the sternum. With respect to the rostrocaudal axis, sternebrae form between the costosternal articulations. Consistent with the biology of endochondral transition, cartilage canals are evident throughout unossified regions of the hyaline matrix. Expanding ossification of adjacent sternebrae results in depletion of the common area of cartilage between the two sternebrae, and eventually in physiologic epiphysiodesis. Fusion of the mesosternebrae reciprocates the initial pattern of sternebral ossification site appearance, proceeding in a caudal-to-cranial direction. Union of adjacent sternebrae, initiated through a central osseous bridge, progresses through anterior, lateral, cephalocaudal, and posterior domains to achieve synostosis. Accessory and bifid centers of ossification within the same intercostal space coalesce prior to adjoining adjacent sternebrae. Manubriosternal fusion is rare due to the presence of a fibrocartilaginous joint restricting ossification. The xiphoid process remains connected to the most caudal mesosternum via a common zone of hyaline cartilage that ossifies by middle to late adulthood. A single pattern of development does not appear fundamental to successful growth of the sternum, as morphological variants were common.

Adolescent↗

PubMed1977

Tibial shaft fractures. A comparison of conservative treatment and internal fixation with conventional plates or AO compression plates.

Out of a series of 207 consecutive fractures of the tibial shaft, 102 were treated conservatively, 64 fractures were treated by AO compression plate osteosynthesis and 41 by internal fixation using Eggers or Lane plates. The choice of method was independent of the extent of soft tissue damage. A follow-up examination of 199 fractures, with a mean observation time of 3.4 years, revealed residual malalignment in 21 per cent of conservatively treated cases and in 8 per cent after conventional plate fixation, while the AO method resulted in anatomical restoration of the axis of the tibia in all cases. However, removal of the compression plates was followed by re-fractures, early and late, in 11 per cent. Implant failure occurred in 5 per cent of both types of plate fixation, and 3 per cent of the conservatively treated cases redislocated. Infection developed in 5 per cent of closed fractures and in 11 per cent of open fractures treated by operative means. Of the conservatively treated cases, only 3 per cent of the open fractures developed infection. The risk of infection following acute internal fixation is thus four times greater than with conservative treatment. AO compression plate fixation shortened the time of fracture healing considerably. The rate of non-union after conservative treatment was 6 per cent in closed and 21 per cent in open fractures. Similarly in conventional plate fixation there was non-union in 8 and 24 per cent, respectively. Non-union was not encountered after AO compression plate osteosynthesis. It is concluded that AO plate osteosynthesis is justified in the treatment of open tibial shaft fractures and also useful in closed fractures when conservative treatment does not lead to stable reduction with a good alignment.

Adolescent↗

PubMed2006

Is microfracture of chondral defects in the knee associated with different results in patients aged 40 years or younger?

PURPOSE: Age-dependent studies about the clinical result after microfracture of cartilage lesions in the knee are still missing. This prospective study was performed to discover age-dependent differences in the results after microfracture over a period of 36 months. METHODS: Between 1999 and 2002, 85 patients (mean age, 39 years) with full-thickness chondral lesions underwent the microfracture procedure and were evaluated preoperatively and at 6, 18, and 36 months after surgery. Depending on the patients' age (< or =40 years or >40 years) and the localization of the defects (femoral condyles, tibia, and patellofemoral joint), the patients were assigned to 6 different groups. Exclusion criteria were meniscal pathologic conditions, tibiofemoral malalignment, and ligament instabilities. Baseline clinical scores were compared with follow-up data by use of paired Wilcoxon tests for the modified Cincinnati knee score and the International Cartilage Repair Society (ICRS) score. RESULTS: The scores improved in all groups over the whole study period (P < .05). Patients aged 40 years or younger had significantly better results (P < .01) for both scores compared with older patients. Between 18 and 36 months after microfracture, the ICRS score deteriorated significantly (P < .05) in patients aged over 40 years whereas younger patients with defects on the femoral condyles and on the tibia showed neither a significant improvement nor a significant deterioration in the ICRS score (P > .1). Magnetic resonance imaging 36 months after surgery revealed better defect filling and a better overall score in younger patients (P < .05). The Spearman coefficient of correlation between clinical and magnetic resonance imaging scores was 0.84. CONCLUSIONS: The clinical results after microfracture of full-thickness cartilage lesions in the knee are age-dependent. Deterioration begins 18 months after surgery and is significantly pronounced in patients aged older than 40 years. The best prognostic factor was found to be a patient age of 40 or younger with defects on the femoral condyles. LEVEL OF EVIDENCE: Level IV, prognostic case series.

Adult↗

PubMed2004

Tibia vara: results of hemiepiphyseodesis.

Tibia vara is a condition characterized by progressive deformity of the proximal tibia resulting in varus malalignment of the lower extremity. An alternative treatment strategy involving lateral hemiepiphyseodesis of the proximal tibia in the skeletally immature has been utilized at our institution for the last 10 years. The study group consisted of 23 patients (16 male, seven female) with 33 involved extremities. The median age at surgery was 11.8 years (range, 7.0-17.3). The median follow-up was 3.1 years (range, 0.8-6.2). Of the patients, 82.6% had a weight greater than the 95th percentile. The preoperative mechanical axis had a median value of 18.0 degrees (range, 5.0-31.0) and at the most recent follow up, a median value of 7.0 degrees (range, -12.0 to 46.0). In 18 (54.5%) extremities, the mechanical axis improved by more than 5 degrees . There was no progression of the overall deformity in 11 (33.3%) extremities. Four (12.1%) extremities had worsening of the deformity. At the time of latest follow up, nine (27.2%) extremities had required corrective osteotomy. Twenty-four (72.7%) were skeletally mature and had not required any further treatment. Goals of hemiepiphyseodesis in adolescent tibia vara or late sequelae of infantile tibia vara include (1) correction of deformity to avoid need for osteotomy, and (2) prevention of progression of the deformity to facilitate subsequent surgery. In this series of patients, 87.8% had either improvement or stabilization of the degree of their deformity.

Adolescent↗

PubMed2003

[Predicting growth patterns after supracondylar fracture of the humerus in childhood].

Supracondylar fracture of the humerus is the most frequently investigated fracture in children. However, systematic studies about postoperative growth patterns cannot be found in the literature. In this retrospective study, the authors attempt to delineate the configuration of supracondylar fractures which allow spontaneous correction of a malalignment or cause post-traumatic growth disturbances. The study included 256 children with supracondylar fracture of the humerus: 184 of them (71.9%) were available for longterm follow-up. The plain films of these children were reviewed and the Baumann and shaft-capitulum angles recorded. Spontaneous correction of a primarily displaced fracture was found in 13.0% ( n=21) of all fractures in the sagittal plane. Spontaneous correction in the frontal plane could not be shown. Growth disturbance was discovered in 10.5% ( n=16) in the frontal plane. No growth disturbance was demonstrated in the sagittal plane. The relatively small number of growth disturbances can be attributed to the low growth potential of the distal physeal plate of the humerus. Growth disturbances with secondary rotational errors were not observed in this study. Spontaneous corrections of alignment in the sagittal plane are only possible under a certain age. Spontaneous correction in the frontal plane, however, is inadequately assessed with this study. The design of a prospective study was formulated to assess how to improve the therapeutic management of supracondylar fractures and to answer additional open questions. Follow-up radiographs and standardized clinical evaluations have to be performed at the time of first free range of movement and 2 years after the trauma. This study will investigate whether therapeutic progress at follow-up is better evaluated with radiological or clinical means.

Adolescent↗

PubMed2005

[Ankle arthrodesis for congenital absence of the fibula].

THE PROBLEM: Bilateral congenital absence of the fibula in a 10-year-old boy. A marked valgus malalignment at the left ankle and a foot with three rays caused pain during standing and walking. Ortheses did not help. Therefore, various treatment options were considered such as amputation of the foot, a supramalleolar correction osteotomy, and a tibiotalar arthrodesis. THE SOLUTION: Correction of malalignment and ankle arthrodesis stabilized with an external mini-fixator while sparing the distal tibial physis. SURGICAL TECHNIQUE: Two skin incisions: one on the medial side visualizing the flexor tendons and the neurovascular bundle while sparing the sural nerve and the small saphenous vein. Exposure of the medial malleolus after division of its ligamentous and capsular attachments. Localization of the ankle joint. The second incision on the lateral side. Z-lengthening of the sole peroneal tendon. Opening of the ankle joint at the lateral and anterior aspect. Resection of the articular surfaces of tibia and talus based on a preoperatively made drawing that showed an alignment of the hindfoot with the longitudinal axis of the tibia and the foot in 90 degrees in relation to the leg. Temporary insertion of a Kirschner wire from the sole of the foot into the tibia to maintain the obtained correction. Placement of a mini-fixator: one threaded Kirschner wire crosses the talocalcaneal synostosis, the second the distal tibial epiphysis, and the third one the proximal third of the tibia. Once the frame is mounted, compression of the resection surfaces and slight distraction between the proximal and middle Kirschner wires. RESULT: At the age of 16 years the boy is able to use a regular shoe with an orthotic insert; he is pain-free and can participate in all daily activities. The growth of the tibia has not been affected.

Ankle Joint↗

PubMed2000

Transverse lag screw fixation in midline mandibulotomy. A case series.

Vertical midline mandibulotomy has provided a relatively simple and efficient means of obtaining access to intraoral tumors that are too large or too posterior to be removed transorally. Midline mandibulotomy has had the advantage of nerve and muscle preservation and places the osteotomy outside the typical field of radiotherapy, in contrast to lateral and paramedian osteotomies. Plate and screw fixation has been the usual means of osteosynthesis for these mandibulotomies; however, plate contouring over the symphyseal surface has been a time-consuming process. Unless the plate was contoured exactly, mandibular malalignment and malocclusion in dentulous patients has occurred. Use of parallel transverse lag screws has become a popular method of osteosynthesis for parasymphyseal fractures, and we have extended their use for mandibulotomy fixation. This paper reports our clinical experience with transverse lag screw fixation of midline mandibulotomies in 9 patients from 1994 to 1997. There were 7 men and 2 women with a mean age of 56 (range 35 to 71 years). The pathological diagnosis in all patients was squamous cell carcinoma; 8 cases were primary, and 1 patient presented with recurrent tumor. No tumors involved the mandibular periosteum. One patient had had previous radiotherapy, and 3 patients underwent postoperative radiotherapy. The mean follow-up has been 17 months (range 9 to 27). There was 1 minor complication and 1 major complication related to our technique. The major complication was a delayed nonunion of the mandibulotomy. This occurred because the 2 parallel screws were placed too close to one another, and this placement resulted in a delayed sagittal fracture of the anterior cortex and subsequent nonunion. Transverse lag screw fixation has not affected occlusion in our dentulous patients. Speech and diet were normal in the majority of our patients. Transverse lag screw fixation of the midline mandibulotomy has been a relatively safe, rapid, and reliable method for tumor access and postextirpation mandibular stabilization and has significant advantages over other current methods of mandibulotomy and fixation.

Adult↗

PubMed2003

Surgical correction of deformities of the distal radius due to fractures in pediatric patients.

INTRODUCTION: The indication and treatment of malunited fractures of the distal radius in the growing skeleton differ from those for adults. The literature results are scarce. In this study we examined the results of surgical correction following fractures of the distal radius in infants. MATERIALS AND METHODS: Seven infant patients with malaligned fractures of the distal radius that demonstrated significant functional deficit and poor prognosis for spontaneous recovery were treated with surgical correction. Two of them were treated because of growth disturbance from post-traumatic closure of the distal radial physis. RESULTS: All seven osteotomies healed with acceptable radiologic alignment. After an average follow-up period of 3 years and 1 month (range 10 months to 8 years and 4 months), patients had an average range of wrist motion (ROM) of 131 deg in extension and flexion (93% of the contralateral side, 130% of presurgical situation); 65 deg in ulnar and radial deviation (94% of the contralateral side, 122% of presurgical situation); and 177 deg in pronation and supination of the forearm (97% of the contralateral side, 115% of presurgical situation). The average grip strength of 71.4 kPa was nearly equal to the other side with 72.8 kPa. The average postoperative angulation of the distal radius was 12 (range 10-17) deg, the radial inclination 20 (range 12-30) deg, and the ulnar variance was -0.6 (range -3 to +2) mm. According to the Fernandez point score system as well as the scale of Fernandez, there were five excellent results and two good results. The patients described low disability on the DASH scores, with a median of 4 (range 0-41) points. CONCLUSIONS: Surgical correction for malunited fractures of the distal radius provides good and excellent radiological and functional results in the growing skeleton. It should be considered immediately if there is poor remodeling capacity and disabling loss of function.

Adolescent↗

PubMed1991

Fusion of the occiput to the upper cervical spine. A review of 37 cases.

This is the first report of a large series of patients undergoing preoperative traction to reduce spinomedullary compression from cranial settling. In all cases, an attempt was made to reduce the malalignment with Gardner-Wells or halo traction before posterior fusion. One patient required an anterior retropharyngeal decompression of the odontoid performed as a one-stage procedure at the time of the posterior operation, and two required subsequent anterior transoral-transpharyngeal resection of the odontoid. From 1974 to 1989, 37 patients underwent posterior occipital cervical arthrodesis. All cases presented with neurologic deficit, and most had signs of brain stem compression, such as L'hermitte's sign or Ondine's curse. The most common cause of basilar impression was rheumatoid arthritis, neoplastic destruction, previously failed C1-C2 fusion, or Down's syndrome. Mean postoperative follow-up was 2 years and 10 months; the patients with less than 2 years' follow-up were followed until successful fusion. Eight of 9 patients with L'hermitte's sign or Ondine's curse and 10 of 12 patients with intractable occipital pain were relieved of their symptoms after reduction and triple-wire stabilization-fusion. Eighteen of 25 patients with long tract signs improved after surgery. Interestingly, 14 (93.3%) of 15 patients with myelopathy improved when successful preoperative reduction of their deformity occurred, whereas only 4 (40%) of 10 patients with fixed basilar impression improved (chi 2 = 8.57, P = .014). Symptoms such as Ondine's curse, L'hermitte's sign, intractable occipital headache, and myelopathy are usually relieved by skeletal traction and posterior fusion without need of an additional transmucosal anterior procedure.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed2006

Surgical simulation of instrumented posterior occipitocervical fusion in a child with congenital skeletal anomaly: case report.

STUDY DESIGN: Case report of a child with a congenital skeletal anomaly who underwent instrumented surgery at the craniovertebral junction (CVJ). OBJECTIVES: To describe the utility of surgical simulation using three-dimensional full-scale models for preoperative planning. SUMMARY OF BACKGROUND DATA: Instrumented fusion of cervical spine with pedicle screws has several advantages compared with conventional sublaminar wiring, such as stronger fixation and reduction of malalignment. However, studies have reported a risk of injury to the vertebral artery (VA) from the insertion of screws. Especially in pediatric patients, the safety of pedicle screw insertion has not been fully established. METHODS: A 7-year-old girl with a congenital skeletal anomaly presented with gait disturbance and clumsiness of her right hand. Radiographs showed dysplasia of the C1 posterior arch, leading to compression of the spinal cord posteriorly. Data from three-dimensional computed tomography (CT) angiography showed that the right VA was dominant and was shifted medially at the C2 pedicle. A surgical procedure was scheduled to resect the C1 posterior arch and perform an instrumented occiput-C2 fusion with a system of rod and screws. To evaluate the adaptation of the system to the small and deformed anatomic structure of her CVJ, we produced a three-dimensional full-scale model from CT data and performed a simulation of the scheduled surgery. RESULTS: Simulation of the surgery on the model showed acceptable adaptation of the system. However, the right C2 pedicle screw penetrated the medial wall of the VA foramen. In response to these results, we altered the surgical procedure and performed occiput-C3 fixation with a system of contoured loop and wiring. Although the patient had to use a halo-vest for 2 months, no complication occurred during surgery, and she experienced relief of her myelopathy after surgery. CONCLUSIONS: The three-dimensional full-scale model was useful for determining the safety of instrumented posterior occipitocervical fusion for a pediatric patient with a skeletal anomaly.

Atlanto-Occipital Joint↗

PubMed2000

High tibial osteotomy with a calibrated osteotomy guide, rigid internal fixation, and early motion. Long-term follow-up.

BACKGROUND: We studied the results of sixty-four valgus-producing high tibial osteotomies performed with the use of a calibrated osteotomy cutting guide and rigid internal fixation, and followed by early motion, in fifty-six patients who had medial unicompartmental osteoarthritis and varus malalignment. Long-term studies have demonstrated that a high tibial osteotomy performed with staple fixation and followed by immobilization in a cast has an expected survival rate of approximately 85 percent at five years and 60 percent at ten years (in studies of ninety-five knees and 213 knees, respectively). To the best of our knowledge, there are no long-term reports on high tibial osteotomies performed with a calibrated osteotomy cutting guide and rigid internal fixation and followed by early motion. METHODS: The indications for high tibial osteotomy were medial unicompartmental osteoarthritis and varus malalignment. A lateral closing-wedge osteotomy was performed. The patients were reexamined to obtain a knee score, to make lateral radiographs of both knees, and to make a full-length anteroposterior radiograph (showing the entire lower extremity, including the hip and ankle) of the involved knee with the patient standing. RESULTS: Twenty-one knees were treated with a subsequent total knee arthroplasty at an average of sixty-five months after the high tibial osteotomy. The remaining forty-three knees had a good or excellent clinical result, with an average knee score of 94 points at an average of 8.5 years after the osteotomy. Survivorship analysis showed an expected rate of survival, with conversion to a total knee arthroplasty as the end point, of 85 percent at five years and 53 percent at ten years. No patient had patella baja postoperatively. There were six complications: four superficial wound infections, one superficial-vein thrombosis, and one delayed union (union occurred at five months). CONCLUSIONS: High tibial osteotomy has been criticized because of a high rate of complications, a loss of effectiveness with time, and the difficulty of conversion to a total knee arthroplasty secondary to patella baja. In our series, in which an osteotomy was performed with a calibrated osteotomy cutting guide and rigid internal fixation and was followed by early motion, the rate of complications was low and approximately two-thirds of the knees had a good or excellent clinical result at an average of 8.5 years. Conversion to a total knee arthroplasty was accomplished without difficulty in the patients who had this procedure. We highly recommend high tibial osteotomy with a calibrated osteotomy cutting guide, rigid internal fixation, and early motion for patients who wish to continue an active lifestyle.

Adult↗