Hardware Loosening Research Articles

Variable Pitch Headless Compression Screw Treatment of Distal Phalangeal Nonunions

Nonunions of the shaft of the distal phalanx, as opposed to the tuft, are usually symptomatic enough to warrant treatment. One method that has proven successful while minimizing complications is compression fixation using variable pitch headless screws inserted percutaneously. Eighteen patients (15 males, 3 females) with a mean age of 48 years were so treated under digital block anesthesia. Seven of 18 (39%) patients were smokers. All initial injuries were crush trauma to the distal phalanx with 10/18 (56%) initially open fractures. Treatment was to 3 thumbs, 6 index fingers, 6 long, 2 ring, and 1 small. Fixation was with micro-sized variable pitch cannulated headless screws except 1 case that used 2 noncannulated threaded taper pins to compress a 3 fragment nonunion. Surgery to treat nonunion occurred at a mean of 13 weeks after the initial injury. Time to union was determined by combined clinical and radiographic assessment. The clinical criterion for union was the absence of pain at the nonunion site with application of maximum pinch pressure to the ipsilateral thumb or finger. The radiographic criteria for union was bridging trabeculae seen on 2 or more cortices and the absence of any signs of hardware loosening, using standard posteroanterior and lateral projections. All 18 patients went on to achieve union at a mean of 9 (±2.8) weeks after surgery. Complications specifically sought out but not identified were infection, loss of reduction, further comminution, hardware loosening, secondary surgery, nail deformity, and continued pain precluding successful pinch.

Descending Aortic Injury by a Thoracic Pedicle Screw During Posterior Reconstructive Surgery

Case report. To describe an iatrogenic aortic injury by pedicle screw instrumentation during posterior reconstructive surgery of spinal deformity. Iatrogenic major vascular injuries during anterior instrumentation procedures have been reported by several authors, but there have been few reports regarding iatrogenic major vascular injuries during posterior instrumentation procedures. A 57-year-old woman with thoracolumbar kyphosis due to osteoporotic T12 vertebral fracture underwent posterior correction and fusion (T10-L2), using segmental pedicle screw construct concomitant with T12 pedicle subtraction osteotomy. Postoperative routine plain radiographs and computed tomography myelography demonstrated a misplaced left T10 pedicle screw, which was in contact with the posteromedial aspect of the thoracic aorta, and suspected penetration of the aortic wall. The patient underwent removal of the pedicle screw, and repair of the penetrated aortic wall through a simultaneous anterior-posterior approach. The patient tolerated the procedure well without neurologic sequelae, and was discharged several days after removal of a left tube thoracostomy. Plain radiographs demonstrated solid fusion at the osteotomy site and no loosening of hardware. Preoperative neurologic symptoms improved completely at 18-months follow-up. Use of pedicle screw instrumentation has the potential to cause major vascular injury during posterior spinal surgery, and measures to prevent this complication must be taken. Timely diagnosis and treatment are essential to prevent both early and delayed complications and death.

Therapeutic efficacy of augmentative plate fixation in long-bone hypertrophic nonunion subsequent to intramedullary nailing

To determine the therapeutic efficacy of augmentation plate fixation in nonunion of long-bone fracture after interlocking intramedullary nailing. From April 1998 to April 2009, 14 patients with long-bone hypertrophic nonunion after intramedullary nail internal fixation were treated with augmentative plate. There were nine patients with nonunion of femur, three of humerus and two of tibia. After implanting the intramedullary nail in situ, an augmentative plate fixation was applied to the fracture site to counter the rotational instability. A general plate with at least two screws reaching the opposite cortical bone above and below the fracture was fixated to the lateral side of bone shaft. In all patients, the rotational instability of fracture site was verified intra-operatively in all cases. However, motion disappeared after plate augmentation. All patients achieved radiological solid union at an average of 8 months (range: 6 - 11). Hardware was removed in six cases at 6-11 months post-operation. No infection, hardware loosening or rupture was found. The augmentative plate fixation can be applied at the fracture site to prevent the rotational instability. Augmentation plate fixation is indicated for femoral and tibial nonunion of proximal or distal metaphyseal-diaphyseal junctional areas, primary comminuted fracture and humeral nonunion after intramedullary nailing.

Improving diagnostic criteria for Propionibacterium acnes osteomyelitis: A retrospective analysis

The identification of Propionibacterium acnes in cultures of bone and joint samples is always difficult to interpret because of the ubiquity of this microorganism. The aim of this study was to propose a diagnostic strategy to distinguish infections from contaminations. This was a retrospective analysis of all patient charts of those patients with >or=1 deep samples culture-positive for P. acnes. Every criterion was tested for sensitivity, specificity, and positive likelihood ratio, and then the diagnostic probability of combinations of criteria was calculated. Among 65 patients, 52 (80%) were considered truly infected with P. acnes, a diagnosis based on a multidisciplinary process. The most valuable diagnostic criteria were: >or=2 positive deep samples, peri-operative findings (necrosis, hardware loosening, etc.), and >or=2 surgical procedures. However, no single criterion was sufficient to ascertain the diagnosis. The following combinations of criteria had a diagnostic probability of >90%: >or=2 positive cultures + 1 criterion among: peri-operative findings, local signs of infection, >or=2 previous operations, orthopaedic devices; 1 positive culture + 3 criteria among: peri-operative findings, local signs of infection, >or=2 previous surgical operations, orthopaedic devices, inflammatory syndrome. The diagnosis of P. acnes osteomyelitis was greatly improved by combining different criteria, allowing differentiation between infection and contamination.

Application of atlantoaxial pedicle screw system in the treatment of upper cervical injury

Objective To investigate the methods, feasibility, outcome and indications of atlantoaxial pedicle screw system in the treatment of upper cervical injury. Methods Thirteen patients with upper cervical injury were treated by atlantoaxial pedicle screw system. There were four patients with old odontoid fractures, two with new odontoid fractures (Aderson ⅡC), three with rapture of the transverse ligament of C1 and four with C1 fracture. Results A total of 26 pedicle screws and 26 pedicle screws were implanted. The mean operation time and perioperative blood loss were 2.6 hours and 470 ml, respectively. No injury to the vertebral artery and spinal cord was observed. All patients were followed up for 4-25 months (mean 13 months). The clinical symptoms were improved to some extent according to Japanese Orthopedic Association scoring system, with improvement rate of 72%-91% (mean 81%). The screws were verified to be fixed in a proper position, and no hardware broken or loosening was observed except for one C1 screw penetrating the medial superior cortex of lateral mass for 3 mm without affecting occipito-aflantal motions. All patients had a solid bony fusion 3-6 months later. Conclusion The atlantoaxial pedicle screw system is feasible in the treatment of upper cervical injury with the advantages of better outcomes and wider indications. Key words: Spinal injuries; Atlas; Cervical vertebrae; Spinal fusion

SYNDESMOSIS FIXATION IN BIMALLEOLAR WEBER C ANKLE FRACTURES;

Objective: To study the influence of size of screws for syndesmosis fixationin bimalleolar Weber C ankle fracture. Design: A prospective randomised controlled clinical trial. Place and Durationof Study: Orthopaedic Department at Combined Military Hospital Malir. Period: From October 2002 to September2005. Patients and Methods: 17 consecutive young active patients with Weber type C bimalleolar ankle fractureshaving syndesmotic injuries treated with open reduction and internal fixation were randomly allocated to two groups.1 2 In group I (n = 9) 3.5mm small fragment and in group II (n =8) 4.5mm large fragment AO cortical screws were usedfor syndesmotic fixation. All patients were followed up for 12 months. Fracture healing or loss of reduction ofsyndesmosis was taken as the study end point. Hardware loosening or breakage and need for hardware removal werethe outcome measures. Subjective and objective assessment with Olerud-Molander Ankle (OMA) scores , range of 1motion and radiographic criteria was done. Results: Loss of reduction was not seen in any patient in both groups.Comparing two groups using paired sample t-test, there was no difference in screw loosening and breakage (p values> 0.05). We did not find a statistically significant difference between range of motion (p = 1.08) and OMA score (p-value= 0.805). Conclusion: Size of the syndesmotic screw does not appear to influence healing of syndesmotic injury.Screw loosening, which can result in reduced range of ankle motion postoperatively was more common in smallerscrew group though the difference was not significant.

Open Reduction and Internal Fixation Compared With Excision for Unstable Displaced Fractures of the Radial Head

To determine if excision of the radial head for treatment of an unstable, displaced fracture is associated with a higher rate of early complications or late arthrosis as compared with open reduction and internal fixation (ORIF). Unstable, displaced fractures of the radial head treated with either excision (15 patients) or ORIF (13 patients) were compared. Implants were removed routinely during the study period. Three patients had instability after radial head excision: 2 were treated in a cast and 1 had temporary pinning of the ulnohumeral joint. Two patients in the ORIF cohort had failure of fixation that subsequently was treated with radial head excision: 1 had early hardware loosening and 1 developed a nonunion. At the 1-year follow-up evaluation there were no significant differences in the flexion or rotation arc. An average of 17 years after injury there was no significant difference in the flexion arc or rotation arc. One result was rated as unsatisfactory in each cohort according to the Mayo Elbow Performing Index. The average Disabilities of the Arm, Shoulder, and Hand (DASH) score was 5 points in the ORIF cohort and 15 points in the excision cohort. Eight patients in the excision cohort had arthrosis (5 mild, 2 moderate, 1 severe) compared with 2 patients in the ORIF cohort (1 mild, 1 moderate). Open reduction and internal fixation of an unstable, displaced fracture of the radial head occasionally fails, but it seems to reduce the risk of subsequent elbow dislocation and to protect against long-term arthrosis. Therapeutic III.

Postoperative Infections of the Thoracic and Lumbar Spine

We retrospectively reviewed 18 consecutive patients (age range, 19-81 years; average age, 55 years) with postoperative infections of the spine. Postdiscectomy-laminectomy infections confined to the disc space (n = 2) were treated with percutaneous transpedicle drainage. Open débridement was performed in patients with an epidural or paraspinal abscess (n = 3). Infections after posterior instrumentation that manifested during the first postoperative month were treated with single (n = 3) or multiple débridements and delayed closure (n = 7), with preservation of instrumentation. Infections that presented more than 9 months after the initial operation (n = 3) were treated with open débridement and removal of instrumentation. The minimum followup was 1 year (mean 2 years, range, 1-4 years). Infections in 17 of the 18 patients resolved effectively and one patient with metastatic cancer died of sepsis. Transpedicle drainage resulted in immediate relief of back pain. Instrumentation can be retained safely in patients with infections that manifest during the first month after implantation. Single surgical débridement is effective in selected cases. After repeated débridements, the presence of healthy granulation tissue in the wound and decreasing C-reactive protein activity were associated with safe and effective wound closure. Despite radiographic evidence of hardware loosening in infections manifested more than 9 months after implantation, we removed hardware without destabilizing the spine.

Influence of Cryosurgery on Treatment Outcome of Low-grade Chondrosarcoma

Successfully managing low-grade chondrosarcomas with margins considered less than wide would minimize the need for extensive reconstruction. We report our experience using cryotherapy as an adjuvant to treat patients with low-grade intracompartmental chondrosarcomas. Ten consecutive patients had intralesional resections including curettage, cryo-surgery, and polymethylmethacrylate application. Eight of these patients required prophylactic skeletal stabilization. We retrospectively reviewed the outcomes for tumor recurrence, disease progression, and complications. The Musculo-skeletal Tumor Society rating scale was used to evaluate functional outcome, and the mean score was 27 points (range, 25-30 points). The mean age of the patients was 54.4 years (range, 29-83 years), and the average followup was 38.5 months (range, 24-60 months). Patients were treated for lesions of the femur (n = 3), humerus (n = 3), scapula (n = 2), tibia (n = 1), and acetabulum (n = 1). There was no evidence of recurrence or metastases. At the latest followup, all patients were well, however, one patient had hardware loosening. In this small group of patients, intralesional resection with adjuvant cryoablation provided an alternative to more radical procedures for low-grade intracompartmental chondrosarcoma.

Triangular Osteosynthesis of Vertically Unstable Sacrum Fractures: A New Concept Allowing Early Weight-Bearing

Presentation of a new triangular osteosynthesis technique that permits early weight-bearing in vertically unstable sacral fractures. : Retrospective evaluation of a consecutive series. Level I trauma center. Thirty-four patients, twenty-eight of whom were poly-traumatized, all with vertically unstable sacral fractures. This group included eight women and twenty-six men, with a mean age of thirty-five years. Average time between trauma and definite operation was thirteen days (range 0 to 28 days). All patients underwent triangular osteosynthesis using a combination of a vertical vertebro-pelvic distraction osteosynthesis (pedicle screw system) and a transverse fixation of the sacrum fracture with either iliosacral screws or trans-sacral plating. Immediate postoperative weight-bearing was permitted postoperatively. Nineteen patients were treated with early progressive weight-bearing and advanced to full weight-bearing, on average, after twenty-three days (range 8 to 70 days). Three of the thirty-four patients (9 percent) experienced loosening of hardware, including two patients (6 percent) who required secondary intervention because of loss of the original reduction. Further complications included one pulmonary embolism (3 percent), one iatrogenic nerve lesion (3 percent), one wound necrosis (3 percent), and two local infections (6 percent). Triangular osteosynthesis is a demanding procedure that can be performed on vertically unstable sacral fractures to allow early progressive weight-bearing with an acceptable complication rate.

Orthopedic Hardware Complications Diagnosed with Multi–Detector Row CT

To retrospectively evaluate multi-detector row computed tomography (CT) for the depiction of orthopedic hardware complications in the spine and appendicular skeleton. This HIPAA-compliant study had institutional review board approval; patient informed consent was not required. Results of 114 multi-detector row CT studies performed because of possible hardware complications in 109 patients (57 men, 52 women; mean age, 44 years; age range, 12-82 years) were available for analysis. The CT studies were retrospectively reviewed and compared with clinical or surgical outcomes, which were used as the reference standard. In another experiment, detection of hardware complications on radiographs and multi-detector row CT images was compared between two readers for selected cases (18 positive and 26 negative) by using receiver operating characteristic (ROC) methods. For 91 (80%) of 114 multi-detector row CT studies, the complication status could be determined on the basis of clinical or surgical outcomes. Twenty-three multi-detector row CT studies were confirmed to be positive (revealing 10 cases of nonunion, five cases of hardware malplacement, three cases of hardware loosening, three perihardware fractures, and two chronic infections), and 57 were confirmed to be negative. There were three false-positive and eight false-negative multi-detector row CT studies. With clinical or surgical outcomes as the reference standard, the sensitivity, specificity, and positive and negative predictive values of multi-detector row CT were 74% (23 of 31 studies), 95% (57 of 60 studies), 88% (23 of 26 studies), and 88% (57 of 65 studies), respectively. Results of ROC analysis indicated that detection of hardware complications was much lower with radiography than with multi-detector row CT (area under ROC curve, 0.84 vs 1.00; F = 4.69, df = 1, 43; P < .05). Multi-detector row CT is an effective tool for depicting orthopedic hardware complications.

Metal concentrations in the serum and hair of patients with titanium alloy spinal implants.

A retrospective study of serum and hair metal concentrations in patients with titanium alloy spinal implants was performed. To determine the incidence and possible causes of abnormal metal concentrations. Several studies have demonstrated that metal debris are present in the tissues surrounding titanium alloy spinal implants. However, few studies suggest that metals dissolve, circulate in the body fluid, and accumulate in remote organs. Titanium, aluminum, and vanadium concentrations in serum and hair were measured after surgery in 46 patients with titanium alloy spinal implants (12 patients in the implant failure group and 34 patients in the no implant failure group) and 20 patients without spinal implants (control group). All the subjects were examined again 1 year after the first examination or implant removal. Of the 46 patients with titanium alloy spinal implants, 16 patients (34.8%) exhibited abnormal serum metal concentrations and 11 patients (23.9%) exhibited abnormal hair metal concentrations. In the control group, three patients (15%) exhibited only abnormal serum and metal aluminum concentrations at the first examination. In both of the two patients who exhibited abnormal serum titanium concentrations and then had their spinal implants removed, the serum and hair titanium levels decreased to beneath the reference value limit in 1 year after the removal. Comparison of the implant failure and no implant failure groups showed no significant differences in the incidence of abnormal serum concentrations of titanium, aluminum, or both metals. Therefore, serum metal concentrations did not seem to be a useful indicator of hardware loosening or implant failure. Approximately one third of patients with titanium alloy spinal implants exhibited abnormal serum or hair metal concentrations at a mean time of mean 5.1 years after surgery. Titanium or aluminum may travel to distant organs after dissolution of metals from the spinal implants.

Bilateral occlusion of common iliac artery following anterior retroperitoneal approach for lumbar fracture instrumentation

There are only four reports on unilateral occlusion of the common iliac artery following ipsilateral anterior retroperitoneal approach to the lumbar spine. To the authors' knowledge, there are no previous reports on delayed bilateral iliac artery occlusion following retroperitoneal approach. We report on a rare case of a 37-year-old paraplegic man who sought this department with bilateral iliac artery occlusion and simultaneous unilateral thromboembolism to the left popliteal artery. The problem occurred following retroperitoneal approach for instrumentation of an L2 fracture performed 2 years ago. The left leg was amputated above the knee because of gangrene, while a left-sided abdominal-to-femoral artery bypass was performed to salvage the right leg. Six months later, the right leg was amputated below the knee because the patient was admitted again with gangrene of his right foot. Following that, the loosened anterior hardware was removed via a right retroperitoneal approach. Revision surgery revealed an apposition of the common iliac vessels from the loosened hardware, while the vertebral bodies at the affected area were severely osteoporotic. Spine surgeons should be aware for the appearance of this disastrous complication following anterior retroperitoneal surgery in patients with loss of sensation in the lower extremities who do not present subjective symptoms of ischemia. The presence of hardware loosening and migration, loss of correction and pseudarthrosis are the warning signs for diagnosis of such a complication.

Orthopaedic Implant-Related Sarcoma: A Study of Twelve Cases

Sarcoma developing in association with a metallic orthopaedic prosthesis or hardware is an uncommon, but well recognized complication. We review 12 cases of sarcomas arising in bone or soft tissue at the site of orthopaedic hardware or a prosthetic joint. Nine patients were male, and three were female. Their ages ranged from 18 to 85 (mean 55) years at the time of diagnosis of the malignancy. Five patients had undergone hip arthroplasty for degenerative joint disease, four had been treated with intramedullary nail placement for fracture, two had staples placed for fixation of osteotomy, and one had hardware placed for fracture fixation followed years later by a hip arthroplasty. The time interval between the placement of hardware and diagnosis of sarcoma was known in 11 cases and ranged from 2.5 to 33 (mean 11) years. The patients presented with pain, swelling, or loosening of hardware and were found to have a destructive bone or soft tissue mass on radiography. Two sarcomas were located primarily in the soft tissue and 10 in bone. Seven patients developed osteosarcoma, four malignant fibrous histiocytoma, and one a malignant peripheral nerve sheath tumor. All sarcomas were high grade. Three patients had metastatic disease at the time of diagnosis. Follow-up was available on eight patients: five patients died of disease 2 months to 8 years (mean 26 months) after diagnosis; two patients died without evidence of disease 7 and 30 months after diagnosis; and one patient is alive and free of disease 8 years after diagnosis. Sarcomas that occur adjacent to orthopaedic prostheses or hardware are of varied types, but are usually osteosarcoma or malignant fibrous histiocytoma. They behave aggressively and frequently metastasize. Clinically, they should be distinguished from non-neoplastic reactions associated with implants, such as infection and a reaction to prosthetic wear debris.

Surgical management of Paget's disease.

Orthopedic complications of Paget's disease occur commonly and arise as a result of chronically accelerated bone remodeling in focal regions of the skeleton. Complications include pathologic fractures with delayed union, progressive skeletal deformity, chronic bone pain and pagetic arthritis. The new bisphosphonates have transformed the treatment of Paget's disease in the past decade but have not yet been studied in depth for their ability to prevent orthopaedic complications. Although few patients with Paget's disease ever require surgical intervention, successful operative management of orthopaedic complications has dramatically improved the quality of life for many sufferers. Selected modalities with promising results include total hip replacement for end-stage pagetic arthritis of the hip, total knee replacement for end-stage pagetic arthritis of the knee, proximal tibial osteotomy for painful malalignment of the knees, internal fixation for pathological fractures, and decompressive laminectomy for spinal stenosis. Complications of surgery on pagetic bone include hemorrhage, infection, pathologic fracture, delayed union, nonunion, and aseptic loosening of hardware. Medical, surgical, and rehabilitative modalities provide a wide array of options in managing orthopaedic complications of Paget's disease and are useful in improving quality of life for sufferers of the condition. Prospective studies are needed to assess the ability of antipagetic medications to prevent severe long-term complications such as deformity, arthritis, and malignancy. Localization of susceptibility genes for Paget's disease may accelerate identification of targets for gene therapy and disease prevention.

Internal Fixation of the Sternum in Median Sternotomy Dehiscence

Sternal dehiscence may be defined as separation of the bony sternum and manubrium following median sternotomy. It may occur at any time postoperatively and has various etiologies. Restoration of sternal integrity in sternal dehiscence is a challenging problem, particularly when associated with deep-seated infection. This report reviews a single-stage technique that virtually eliminates the infected sternotomy wound and provides anatomic reduction and stabilization of the sternum. Complete debridement of infected and/or nonviable soft tissue, bone, and cartilage is followed by pulse irrigation. Parallel stainless steel mandibular reconstruction plates are then placed on each side of the remaining sternum and wired together. One or more transmanubrial compression plates may be added. Bilateral pectoralis major musculocutaneous flap advancement and primary skin closure is performed over two to three closed suction drains. From January of 1994 to July of 1996, this technique was used by the same surgeon in 26 male and 4 female patients aged 43 to 78 years (x = 61). Indications for the operation were sternal dehiscence with infection (osteomyelitis and/or mediastinitis) in 14 patients and sternal dehiscence without infection in 16 patients. All patients survived to discharge with mean time on the ventilator, intensive care unit length of stay, and postoperative length of stay of 0.7, 2, and 8 days, respectively. Choice and duration of antibiotics were based on culture results and operative findings. Subsequent hardware removal was necessary in one patient for hardware loosening and three patients for late periplate infection. A closed wound was eventually achieved in all 30 patients, and sternal stability was restored in 29 patients. In the management of sternal dehiscence, the described technique of internal fixation can provide anatomic sternal reduction and stabilization, elimination of infection, and wound closure in a single-stage operation. Successful outcomes were achieved despite the presence of severe infection.

Triangular osteosynthesis of vertically unstable sacrum fractures: a new concept allowing early weight-bearing.

Presentation of a new triangular osteosynthesis technique that permits early weight-bearing in vertically unstable sacral fractures. Retrospective evaluation of a consecutive series. Level I trauma center. Thirty-four patients, twenty-eight of whom were polytraumatized, all with vertically unstable sacral fractures. This group included eight women and twenty-six men, with a mean age of thirty-five years. Average time between trauma and definite operation was thirteen days (range 0 to 28 days). All patients underwent triangular osteosynthesis using a combination of a vertical vertebropelvic distraction osteosynthesis (pedicle screw system) and a transverse fixation of the sacrum fracture with either iliosacral screws or transsacral plating. Immediate postoperative weight-bearing was permitted postoperatively. Nineteen patients were treated with early progressive weight-bearing and advanced to full weight-bearing, on average, after twenty-three days (range 8 to 70 days). Three of the thirty-four patients (9 percent) experienced loosening of hardware, including two patients (6 percent) who required secondary intervention because of loss of the original reduction. Further complications included one pulmonary embolism (3 percent), one iatrogenic nerve lesion (3 percent), one wound necrosis (3 percent), and two local infections (6 percent). Triangular osteosynthesis is a demanding procedure that can be performed on vertically unstable sacral fractures to allow early progressive weight-bearing with an acceptable complication rate.

Anterior Cervical Plate Fixation with the Titanium Hollow Screw Plate System

Although anterior cervical plates provide excellent fixation for the anterior column, the potential risk for injury to the spinal cord or soft tissues involved with their use has been the reason they have not gained universal acceptance. Morscher introduced a system that attempts to prevent the migration and loosening of screws by using a cross-split screw head that can be locked into the plate. The secondary advantage of this system is that it eliminates the requirement for posterior cortex purchase and thereby decreases the risk for spinal cord injury. This article reports the authors' experience using the Morscher titanium hollow screw cervical plate system. Forty-two patients in the series underwent anterior cervical arthrodesis for degenerative disease or trauma. The average number of levels fused were two. The fusion rate was 100%. Significant hardware loosening occurred in two patients. There was no iatrogenic injury to the spinal cord or esophagus. In conclusion, the titanium hollow screw cervical plate provides immediate stable fixation with minimal complications. Its use should be considered in the surgical treatment of patients requiring multilevel anterior cervical arthrodesis.

Anterior decompression and plate fixation in fracture dislocations of the lower cervical spine

Surgical treatment of unstable traumatic injuries of the cervical spine can be carried out by a posterior or anterior approach, with different advantages and disadvantages. Twenty patients were treated with anterior decompression, interbody fusion with autogenous iliac bone graft, and osteosynthesis with a Louis anterior plate. The screws were inserted in the vertebral body without reaching the posterior vertebral wall. There were 18 male and 2 female patients, aged between 18 and 66 years (average 36 years). The osteoarticular lesion was in 8 cases a tear-drop fracture and in 12 a fracture-dislocation. The mechanisms of injury were flexion-compression, flexion-rotation, hyperflexion, and hyperextension. A complete spinal cord lesion was present in 10 cases, central cord syndrome in 5, isolated radiculopathy in 3, and anterior cord syndrome in 1; one patient had normal neurological function. At long-term followup fusion of the graft was observed in all cases without evidence of spinal malalignment, breakage of the implant, or aseptic hardware loosening. Neurological deterioration was not observed in any case. In one case, complicated by late infection, healing was uneventful after plate removal, surgical debridement, and antibiotic therapy. A fistula of the hypopharynx due to perforation of the piriform recess appeared following repeated bronchoscopy 12 months after surgery. There were no signs of implant loosening and the lesion was surgically repaired. From a neurological point of view the 10 patients with complete cord lesion remained unchanged; those with incomplete cord lesions improved by 1 or 2 degrees on the Frankel scale; those with isolated radiculopathies recovered fully; and the neurologically intact patient remained unchanged. The present study and the data reported in the literature prove that anterior surgery with plate fixation in cervical spine injuries allows the achievement of complete neural decompression by direct visual examination. On the other hand, posterior surgery can result in incomplete decompression and associated neurological deterioration. Anterior plate instrumentation has proved itself mechanically adequate, even if it is less stable than posterior constructs. The advantages of anterior surgery compared to those of posterior surgery are such that several specific risks are acceptable. Posterior surgery is nevertheless indicated if the lesion cannot be reduced preoperatively under closed conditions.

Mersilene tapes as a substitute for wire in segmental spinal instrumentation for children.

Sublaminar wires for segmental fixation have been a useful adjunct to internal fixation of the spine. Concern over broken wires in the spinal canal or fear of cut-through in soft bone led to the use of Mersilene tape to supplement Harrington or Luque rod fixation in six scoliotic children. No problems of infection or hardware loosening were noted. Mersilene tapes for segmental fixation may be useful where there is concern for wires in the spinal canal or with patients with soft bone and flexible curves.