Maxillary post-traumatic outcome correction literature review and our experience. Part I: maxillary bone non-unions-"poor bone positioning"

Still today, there is no classification of non-unions in maxillofacial traumatology. There is a broad spectrum of definitions that simultaneously describe the pathological conditions and functional implications determined by the anatomical location of the fractures and the time factor. In this article the authors describe a literature review about bone non-union classification. Weber, in 1973, introduced the term "pseudo-arthrosis" to describe an altered process of bone healing characterised by the presence of fibrous tissue interposed between the fracture segments, that was lined with cartilaginous tissue and joined by a capsule; Spiessl, in 1988, used the term "non-union" to define any alteration of the bone healing process after a time period of more than 6 months from the initial traumatic event; Rosen, in 1990, proposed a new classification of the modes of altered bone healing in fractures, distinguishing 5 categories: delayed consolidation, non-union, non-union vascular, non union avascular, pseudoarthrosis. The authors also talk about "poor bone positioning". This factor describes the incorrect anatomical position of the bone fragments despite perfectly normal healing according to Gruss. In this article they also discuss about the treatment of non-unions and the treatment of occlusal alterations caused by poor post-traumatic bone positioning.

[New surgical treatment procedures in fractures of the distal tibia (LCP, MIPO)]

All along the operative treatment of distal tibial fractures is a difficult procedure. In most cases the clinical situation is characterized by small distal fragments in combination with crucial soft-tissue conditions. That's why complications as primary or secondary displacements, mal unions, delayed or non unions and as well as a high rate of deep wound infection are often seen. Thus internal fixations with traditional implants (standard screws and plates) could consider inevitable this crucial biology and biomechanics only insufficiently. The nowadays available internal fixators with optional angular-stable screws expand the possibilities of internal fixation in these severe situations. Their minimal invasive application (MIPO, Minimally Invasive Plate Osteosynthesis) takes care of the soft tissue and reduces the surgical trauma furthermore. With the variety of their possible applications (combination of angular stability with standard application) also the demands increase, however, both onto the surgeons, but also onto the general practitioners in the aftercare. The combination of most different tactics in one implant results in the consequence, that at the same bone simultaneously direct and indirect bone healing will be expected. The radiological differentiation between desired and unwanted healing processes becomes thus difficult. Pre- and perioperative procedures require from the trauma surgeon a huge infrastructure and a high measure of biomechanical and biological experience. In the postoperative management of these injuries an unlimited cooperation between traumatologists and general practitioners is indispensable for a further successful course.

Late complications of adult idiopathic scoliosis primary fusions to L4 and above: the effect of age and distal fusion level

STUDY DESIGN A retrospective analysis of primary cases of adult idiopathic scoliosis treated with long instrumented fusions from the thoracic spine proximally to segments that range from T11 to L4 distally.

OBJECTIVE

To analyze whether patients requiring revision surgery had lower postoperative SRS-24 scores; age >or=40 years correlated with higher rates of revision surgery; disc degeneration below the fusion occurred more commonly with a more distal lowest instrumented vertebra or older patient age (>or=40 years); and whether smokers had higher rates of major complications or revision surgery.

SUMMARY OF BACKGROUND DATA

Few reports describe complications related to primary long fusions using modern 2+ rods, hook/pedicle screw instrumentation methods in the treatment of adult idiopathic scoliosis.

METHODS

Sixty-seven patients were analyzed with an average age of 38.8 years (range 21-61 years). The average clinical follow-up was 7.8 years (range 2-16 years): 42 patients had >5 years follow-up, including 23 patients with >10 years follow-up. Patients were categorized by age (< or >or=40 years) and level of the lowest instrumented vertebra (T11-L2 vs. L3-L4). Upright radiographs and postoperative SRS-24 questionnaires from the latest follow-up date were analyzed.

RESULTS

Patients requiring revision surgery had lower total score (average 72.0) than those that did not (total score = 94.2; P = 0.01). More specifically, patients with pseudarthrosis had lower total scores (average 74.7) than those without (average total score = 93.5; P = 0.02). When analyzing age, there were similar rates of pseudarthrosis, but higher rates of transition syndrome (2) and sagittal/coronal imbalance (1 each) in patients >or=40 years. Subsequent distal disc degeneration did not correlate significantly with more distal lowest instrumented vertebra or older patient age. Smokers did not have higher rates of major complications or revision surgery than nonsmokers.

CONCLUSIONS

Patients with adult idiopathic scoliosis and long fusions had similar pseudarthrosis rates, but higher rates of transition syndrome when lowest instrumented vertebra was L3-L4 relative to levels T11-L2. When categorized by age, complication rates were similar in each group. Patients with pseudarthroses or other diagnoses requiring revision surgery had lower SRS-24 total scores than those without (P = 0.02 and P = 0.01, respectively).

[Multiple-level instrumented anterior cervical fusion: a risk factor for pseudoarthrosis? A prospective study with a minimum of 3-year follow-up]

PURPOSE OF THE STUDY

This prospective study with minimal 3-year follow-up was performed to compare fusion rates, course of fusion, collapse incidence and occurrence of subsidence in one- and two-level instrumented anterior cervical fusions (ACDF) and thus to proof the hypothesis that use of internal fixation decreases the risk of non-union in bi-segmental ACDFs to the same level that can be expected in mono-segmental procedure.

MATERIAL

In 79 consecutive patients operated upon by the Smith-Robinson technique for degenerative process of cervical spine in one or two levels was applied single instrumentation system in order to ensure ideal condition for solid bone fusion of 113 grafts (45 in one and 68 in two levels). All the patients were invariably followed for a minimum of 3 years.

METHODS

Radiological criteria were used for evaluation of intervertebral fusion, graft collapse and its subsidence and results were statistically analyzed using M-L Chi-square test for the comparison of fusion and collapse incidence and further Chi-square test for the analysis of fusion course. All these figures were calculated at the level of significance 0.05 (alpha=0.05).

RESULTS

Overall, no significant difference was observed in achieving solid bone fusion 3 years after the surgery in one- and two-level procedures (95.6% vers. 92.6%, p=0.522), neither the bone graft collapse rate was of significant difference (2.2% vers. 7.6%, p=0.208). In single-level group the time to bone fusion was significantly shorter (p<0.001). When pooling the data into autologous and allogenic graft subgroup, there was observed no statistically significant difference in achieving union in autologous subgroup (100% vers. 90.9%, p=0.142); in allogenic subgroup this situation was similar: no significant difference in fusion rate (93.3% vers. 93.5%, p=0.980) was observed. In both auto- and allogenic subgroups monosegmentally implanted grafts fused more readily (p<0.001). There was no case of graft subsidence in any investigated group.

DISCUSSION

Our prospective study did not find any statistically significant difference in graft collapse and fusion rate when comparing one- and two-level instrumented ACDFs 3 years after the surgery. Plating system used in our patients brings more stability to operated segments and thus presumably prevents micromotions in postoperative period. Micromovements seems to be the major risk factor for non-union in non-instrumented multilevel cervical fusion. Other risk factor that should be considered in non-instrumented procedure is increase in compressive forces that are also partially eliminated by the semirigid internal fixation. Significantly delayed time to union observed in two level fusions shows most probably on increased number of surfaces that must be consolidated during the bone-healing process.

CONCLUSION

This study demonstrates that internal fixation used in multilevel ACDF decreases risk of pseudoarthrosis to the same level that can be expected in monosegmental procedures.

Pseudarthrosis after lumbar spine fusion: nonoperative salvage with pulsed electromagnetic fields

We studied 100 patients in whom symptomatic pseudarthrosis had been established at more than 9 months after lumbar spine fusion. All patients were treated with a pulsed electromagnetic field device worn consistently 2 hours a day for at least 90 days. Solid fusion was achieved in 67% of patients. Effectiveness was not statistically significantly different for patients with risk factors such as smoking, use of allograft, absence of fixation, or multilevel fusions. Treatment was equally effective for posterolateral fusions (66%) as with interbody fusions (69%). For patients with symptomatic pseudarthrosis after lumbar spine fusion, pulsed electromagnetic field stimulation is an effective nonoperative salvage approach to achieving fusion.

Stellenwert und Vorteil neuer winkelstabiler Implantate bei Schaftfrakturen (LCP vs. Nagel)

Der goldene Standard zur Behandlung von Schaftfrakturen langer Röhrenknochen des Erwachsenen bleibt nach wie vor die Marknagelosteosynthese. Das operative Verfahren ist standardisiert und meist minimal-invasiv, die primäre Heilungsrate ist hoch, und Komplikationen treten selten auf. Für Problemzonen (metadiaphysärer Übergang), bei schlechter Knochenqualität und bei anderen relativen Kontraindikationen für den Marknagel (enger Markkanal, Frakturen beim Adoleszenten und beim Polytrauma) bieten die neuen winkelstabilen Schrauben-Platten-Systeme (LISS, LCP) eine ausgezeichnete Alternative für die operative Stabilisierung. Die damit erreichte sehr hohe Primärstabilität in Kombination mit neu entwickelten, weichteilschonenden Operationstechniken (MIPO = Minimalinvasive Plattenosteosynthese) bieten die Grundlagen für eine funktionelle Nachbehandlung und eine möglichst rasche und komplikationsarme Knochenheilung.

Complications and outcomes of pedicle subtraction osteotomies for fixed sagittal imbalance

STUDY DESIGN

Radiographic analysis, outcomes analysis (pain scale, Oswestry, SRS-24), and accumulation of complications. Outcomes and complications collected prospectively. Radiographic analysis performed retrospectively.

OBJECTIVES

To assess the benefits and stress complications of pedicle subtraction osteotomies for patients with fixed sagittal imbalance.

SUMMARY OF BACKGROUND DATA

Few reports on pedicle subtraction osteotomies exist in the peer-review literature for conditions other than trauma and ankylosing spondylitis.

MATERIALS AND METHODS

Thirty-three consecutive patients with sagittal imbalance treated with lumbar pedicle subtraction osteotomy at one institution (minimum 2-year follow-up) were analyzed. Complications were also analyzed for the entire group of consecutive pedicle subtraction osteotomies done at our institution to date (n = 66).

RESULTS

For the 33 patients with minimum 2-year follow-up, there were significant improvements in the overall Oswestry score (P 0.0001) and pain score (P = 0.0001). Most patients reported improvement in pain and self-image and reported overall satisfaction based on ultimate SRS-24 questionnaire. There was one pseudarthrosis in the lumbar spine through an area of pedicle subtraction osteotomy (area of previous laminectomy and nonunion), and six patients had thoracic pseudarthroses (levels other than the osteotomy level) and one patient had a pseudarthrosis at L5-S1. Two patients had acute angular kyphosis at the thoracolumbar junction at the proximal end of the construct. Five patients who experienced transient neurologic deficits resolved their deficits after central canal enlargement.

CONCLUSIONS

The clinical result with pedicle subtraction osteotomy is reduced with pseudarthrosis in the thoracic or lumbar spine and subsequent breakdown adjacent to the fusion. For patients with a degenerative sagittal imbalance etiology the results were worse and the complications were higher. Central canal enlargement is critical.

Revision strategies for lumbar pseudarthrosis

Management and avoidance of lumbar pseudarthrosis are among the most common and challenging tasks faced by reconstructive spine surgeons. The risks of pseudarthrosis can be broadly divided into two categories: those within a surgeon's control and those not within his/her control. These include biological factors, graft choices, site preparation, and surgical design. The authors review the biological factors that affect fusion and how they can be manipulated to avoid or manage lumbar pseudarthrosis. Surgical planning and construct design to prevent or treat pseudarthrosis will also be discussed. Additionally, the importance of restoring sagittal balance will be reviewed.

Back pain and function 23 years after fusion for adolescent idiopathic scoliosis: a case-control study-part II

STUDY DESIGN

A consecutive series of patients with adolescent idiopathic scoliosis, treated between 1968 and 1977 before age 21 years with distraction and fusion using Harrington rods (surgically treated: n = 156; 145 females and 11 males) were followed-up at least 20 years after completion of the treatment.

OBJECTIVES

To determine the long-term outcome in terms of back pain and function in patients surgically treated for adolescent idiopathic scoliosis.

SUMMARY OF BACKGROUND DATA

Few reports on long-term outcome of back pain and function have previously been presented for this group of patients. Results presented are not conclusive regarding effects on back pain and its correlation to a fusion extending into the lower lumbar spine.

MATERIALS AND METHODS

One hundred forty-two (91%) of the patients were reexamined as part of an unbiased personal follow-up. This included a clinical examination and evaluation of curve size (Cobb method) and degenerative findings in full standing frontal and lateral radiographs. Validated questionnaires in terms of general and disease-specific quality of life aspects as well as present back and pain symptoms were used. One hundred thirty-nine had complete follow-up. An age- and sex-matched control group of 100 individuals was randomly selected and subjected to the same examinations.

RESULTS

The deterioration of the curves was 3.5 degrees for all curves and eight (5.1%) of the patients treated with fusion had undergone some additional curve-related surgical procedure. The patients had significantly more degenerative disc changes than the controls. Lumbar pain, although mild (2.4 on visual analogue scale), was significantly more frequent among the patients than the controls (65 vs. 47%, P = 0.0079). Only 25% of the patients admitted daily pain, and analgesics were sparsely used. No major differences of back function and general health-related quality of life were noted between the patients or the controls. Except for having been on sick-leave ever because of the back (45% vs. 19%, P = 0.0040) no differences could be seen in sociodemographic variables between the groups. Furthermore, no differences could be found between patients fused to L3 or higher (n = 102) versus L4 or lower (n = 37). No correlation could be found between pain and its localization and various variables on the scoliotic curve, body mass index, or smoking. Persisting discomfort and/or sensory loss were noted significantly more often among the patients who had the autologous bone harvesting performed through a separate incision over the iliac crest (24.3%) than among those in whom this was performed through an elongated midline incision (4.6%, P = 0.0015).

CONCLUSIONS

Minimal pain and no dysfunction occurred (mean) 23 years after fusion for adolescent idiopathic scoliosis compared with normal straight controls. Significantly more pain in the scar region occurred when bone graft from an incision over the posterior iliac crest was used for harvesting bone to the fusion compared with an incision performed as an elongation of the midline incision used for the scoliosis surgery.

Laminoplasty for the treatment of failed anterior cervical spine surgery

Object

Cervical stenotic myelopathy can be treated via anterior or posterior approaches. In anterior cervical decompression and fusion (ACDF), because the risks and likelihood of pseudarthrosis increase with the number of treated segments, attempts are typically made to limit the number of treated levels. Thus, postoperative recurrence of myelopathy following ACDF may occur because stenotic levels were not treated or because adjacent segments have degenerated. Revision decompressive surgery via an anterior approach is one solution; however, if the stenosis involves multiple levels a posterior decompressive laminoplasty can be performed as an alternative.

Methods

Twenty-four cases treated over an 8-year period were identified and data were retrospectively reviewed. In 15 cases posterior decompressive surgery was necessary because of progressive spinal degeneration and stenosis (five cases following initial treatment for radiculopathy, seven after initial treatment for spondylotic myelopathy, and three due to spreading of an ossified posterior longitudinal ligament). In nine cases revision surgery was undertaken because the initial decompression was inadequate.

The mean follow-up period after the second surgery was 16 months. Improvements in myelopathy were seen in 83% of patients (mean improvement of 1.25 points on the Nurick Scale). Preoperative severe gait disorders were associated with poor recovery. Complications included two cases of transient C-5 nerve root palsy and two cases of new persistent axial neck pain.

Conclusions

Laminoplasty is a straightforward and effective treatment for failed ACDF due to inadequate decompression or progressive degeneration of the spinal column, avoiding reentry through scar tissue. In terms of myeolpathic pain, the recovery rate is comparable with that related to revision ACDF.

Management of iatrogenic flat-back syndrome

Iatrogenic loss of lordosis is now frequently recognized as a complication following placement of thoracolumbar instrumentation, especially with distraction instrumentation. Flat-back syndrome is characterized by forward inclination of the trunk, inability to stand upright, and back pain. Evaluation of the deformity should include a full-length lateral radiograph obtained with the patient's knees and hips fully extended. The most common cause of the deformity includes the use of distraction instrumentation in the lumbar spine and pseudarthrosis.

Surgical treatment described in the literature includes opening (Smith-Petersen) osteotomy, polysegmental osteotomy, and closing wedge osteotomy. The authors will review the literature, cause, clinical presentation, prevention, and surgical management of flat-back syndrome.

Outcome after single technique ankle arthrodesis in patients with rheumatoid arthritis

The established treatment for severe rheumatoid arthritis in the ankle is arthrodesis. Numerous reports in the literature describe outcomes in patients with degenerative and posttraumatic arthrosis and rheumatoid disease. This has led to results that are difficult to interpret. In addition, in the few studies that have evaluated patients with rheumatoid disease many techniques of arthrodesis are reported, further confounding assessment of one fusion method. One technique of 20 ankle fusions in patients with rheumatoid disease was evaluated. A modified Wagner arthrodesis was used through a transfibular approach using parallel compression screws. The scoring systems of Mazur et al, Moran et al, and the Short-Form-36 were used to evaluate the outcome. The mean time to followup was 3 years 10 months. Eighteen of 20 fusions obtained a solid talocrural union (90%). No correlation was found between the scores of Mazur et al and Moran et al. Correlation was achieved between the scores for the Short Form-36 and Moran et al. The modified Wagner ankle arthrodesis is a simple, reliable, reproducible technique with a 90% union rate. The value of the technique has been confirmed in patients with rheumatoid arthritis by evaluating the outcome using a scoring system that is validated and relevant to this population.

[Defective forearm pseudoarthrosis with a neglected elbow dislocation]

Neglected elbow dislocations, rarely seen in the developed countries, are very attractive due to the difficulties of treatment and diversity of prognosis. A 32 year-old woman was admitted with chronic elbow dislocation and defective forearm pseudoarthrosis due to an accident four months prior to admission. Open reduction and distraction arthroplasty using hinged external fixator for the elbow, open reduction and internal fixation with plate-screws with fibula allograft for the forearm was performed. The elbow was stable and had 110 degrees and -15 degrees of active flexion and extension respectively on the ninth month of follow-up. Both radius and ulna were united.

Regeneration of the donor side after autogenous fibula transplantation in 53 patients: evaluation by dual x-ray absorptiometry

We determined the degree of fibular regeneration at the donor site, using radiographs and dual x-ray absorptiometry, in 53 patients who underwent autogenous nonvascularized fibular transplantation for tumor reconstruction in long bones (mean follow-up 15 (3-26) years). Logistic regression was used to determine whether gender, age at transplantation, time since transplantation, bone mineral density (BMD), and length of the graft were associated with fibular regeneration. 26 patients had spontaneous complete bone regeneration. Younger age at transplant was the only predictor of fibular regeneration. In predicting fibular regeneration, sensitivity was 96% and specificity 74%, using 15 years of age as a cut-off. In the long-term follow-up, we found only gradual changes in the BMD and the values ranged from 24% to 217%. We found no correlations of bone mineral density with age, gender, length of the graft, or time since transplantation.

[Results of Kapandji-Sauvé procedure with distal radio-ulnar fusion and segmental resection of the ulna]

The Kapandji-Sauvé procedure was performed in 75 patients between 1990 and 2003. The most important indication was painful and restricted forearm rotation after fracture of the distal radius combined with dislocation or destruction of the distal radioulnar joint. 25 patients were followed up using a modified Martini score. We found a significant improvement of forearm rotation, reduction of pain and a good patient satisfaction in a long-term follow-up ranging from three to 12 years.

Tibiocalcaneal Marchetti-Vicenzi nailing in revision arthrodesis for posttraumatic pseudarthrosis of the ankle

The authors conducted a retrospective study of 7 patients treated with tibiotalocalcaneal Marchetti-Vicenzi nailing (one anterograde and six retrograde nails). All these patients had developed pseudarthrosis after previous arthrodesis for posttraumatic ankle fractures. The results were evaluated clinically and radiographically at a median time of four years. Fusion occurred in three patients, in one of them only after removal of the proximal locking screw. Of the remaining four patients, one achieved consolidation after replacement of the Marchetti-Vicenzi nail by another intramedullary nail, two were lost to follow-up after replacement by external or internal fixation, and the last patient developed pseudarthrosis again. At least nine additional interventions were necessary in six patients, including one amputation for intractable pain and severe soft-tissue damage due to the trauma. None of the patients had excellent or good results. The majority was unsatisfied with this type of intramedullary nailing. Therefore our study was terminated prematurely. Revision ankle fusion for nonunion or malunion after external or internal fixation has a high complication rate. Further study is mandatory to prevent or resolve remaining problems.

Atrophic nonunions of the proximal ulna

Ten consecutive patients were treated by one surgeon for an atrophic nonunion of the proximal ulna. There were six men and four women with an average age of 47 years. Nine of the initial injuries were fracture-dislocations (seven posterior Monteggia lesions and two transolecranon fracture-dislocations) and one was a fracture of the proximal ulnar and radial diaphysis. The nonunion was associated with failed operative fixation in nine patients and occurred after treatment in cast in one patient. Three patients had synovial pseudarthroses and eight had bony defects. Debridement of the nonunion, autogenous cancellous bone grafting, and contoured limited-contact plate fixation were done at an average of 36 months after the original injury. The patients were followed up for an average of 39 months. Union was achieved in all 10 patients. The average arc of ulnohumeral motion was 105 degrees and the average arc of forearm rotation was 130 degrees. According to the system of Broberg and Morrey five patients had an excellent result, four had a good result, and one had a fair result. The fair result was attributable to proximal radioulnar synostosis and severe ulnohumeral arthrosis. Atrophic nonunion of fractures of the proximal ulna usually follow a complex injury treated with inadequate fixation. Stable plate fixation and autogenous bone graft predictably lead to union, but the functional result may be limited by associated problems.

Failure of posterior titanium atlantoaxial cable fixation

BACKGROUND CONTEXT

The operative treatment of rotatory atlantoaxial instability remains controversial. The use of cable fixation has largely replaced the use of wire for interlaminar fixation. Although cable fixation offers biomechanical advantages over wire fixation, it is still at risk of fatigue failure. The authors were unable to locate any published reports of fatigue failure of titanium cables in the fixation of atlantoaxial instability.

PURPOSE

The purpose of this case study is to describe an unusual case of fatigue failure of a titanium cable used to aid in atlantoaxial fusion for the treatment of rotatory atlantoaxial instability.

STUDY DESIGN

Case study.

METHODS

We reviewed the medical records and X-rays of a patient with rotatory atlantoaxial instability treated with posterior C1-C2 fusion and atlantoaxial fixation with a titanium multistranded cable, who developed fracture of the cable and migration of the cable into the spinal canal.

RESULTS

The patient was revised with removal of the broken cable, repair of the pseudarthrosis and fixation with atlantoaxial screws.

CONCLUSION

Interlaminar fixation with cables or wires is at risk for failure with potential migration of the wire or cable into the spinal canal. The authors found that failure of the cables or wire can be salvaged with application of transarticular screws.

Direct stabilization of lumbar spondylolysis with a hook screw: mean 11-year follow-up period for 113 patients

STUDY DESIGN

A retrospective study involving 113 patients with a spondylolysis who underwent direct repair with a hook screw was conducted.

OBJECTIVES

Spondylolysis with instability can produce low back pain. In adults, fusion of the affected level is the gold standard of treatment. In the adolescent, direct repair of the lysis can save a functional segment.

SUMMARY OF BACKGROUND DATA

It has been proved that direct repair of spondylolysis can accomplish restitutio ad integrum for a functional segment. So far, only short-term results are available in the literature.

METHODS

This study involved 113 patients who underwent direct repair of spondylolysis with a hook screw according to Morscher. After an average follow-up period of 11 years, the patients were reviewed. The main issue was the question of fusion. For this purpose, plain radiographs were taken. For doubtful cases or for the patient experiencing pain, conventional tomography scans or computed tomography scans were taken.

RESULTS

The pseudarthrosis rate was 13.3%. The fusion rate for patients younger than 14 years was higher than that for older patients, especially those older than 20 years.

CONCLUSIONS

Direct repair of spondylolysis can be recommended for patients with a growing skeleton, a slight slip, an instability, or failure of conservative treatment. Thereby, a functional segment can be saved with a relatively small operation.

Pseudoarthrosis of the cervical spine: a comparison of radiographic diagnostic measures

STUDY DESIGN

A retrospective review was conducted.

OBJECTIVE

To compare the accuracy of two objective radiographic techniques in identifying nonunion after anterior cervical discectomy and fusion.

SUMMARY OF BACKGROUND DATA

The accuracy of diagnostic methods for detecting pseudarthrosis has been poorly documented. Radiographic criteria mentioned in the literature include perceived motion or change in the Cobb angles between the involved segments on flexion-extension views.

METHODS

The participants in this study were 27 patients with 29 cervical fusions ranging from one to three levels. Patients were examined and radiographs obtained. The mean follow-up period was 39 months. Two measurements were obtained from lateral flexion-extension radiographs: Cobb angle and the distance between the tips of the spinous processes of the surgically managed levels. The measurements were obtained independently by three physicians in a blinded fashion.

RESULTS

The reliability among the observers, as measured by Cronbach's alpha, was 0.95 for the spinous process method and 0.74 for the Cobb angle method. A measurement of more than 2 mm between spinous processes was noted in patients with a known pseudarthrosis. The Pearson correlation between pseudarthrosis and use of the spinous process method was 0.77 ( < 0.001). The Pearson correlation between pseudarthrosis and use of the Cobb angle method was 0.28 ( > 0.10). The area under the receiver operating characteristic curve for the spinous process method was found to be 0.980, as compared with 0.662 for the Cobb angle method, for the measurement of pseudarthrosis.

CONCLUSIONS

Measurement of the change in distance between spinous processes is more reproducible and accurate than the Cobb method for making the diagnosis of pseudarthrosis. The authors believe that the measurement of distances between spinous processes on lateral flexion-extension radiographs should be used as a method for evaluating radiographic fusion in patients with pseudarthrosis.

Improvement in technique for arthroscopic ankle fusion: results in 15 patients

We retrospectively assessed time until consolidation, complications, and functional results according to Morgan from the clinical charts and radiographs of 15 arthroscopic ankle fusions. In 11 patients unilateral distraction and crossed screw placement over the fusion area through tibia and fibula were used (group A); in 4 patients a technique of bilateral distraction and parallel screw placement from the dorsal side of the tibia into the neck of the talus was used (group B). In group A there were two cases of insufficient compression at the arthrodesis site, three cases of suboptimal compression, and five cases of malposition of the screws. In all cases in group B good compression and fixation was achieved, and no case of malpositioning of screws occurred. There was nonunion in 3 of 11 patients in group A and in none of the four patients in group B. Time until fusion was 23.3 in group A and 12.5 weeks in group B. Functional results were better in group B. The initial experiences with our technique of bilateral distraction and parallel screw placement are therefore promising. Screw placement is easier and optimal compression and fixation are achieved. We feel that this technique should be considered when performing an arthroscopic ankle fusion.

Microsurgical anterior approaches to the lumbar spine for interbody fusion and total disc replacement

OBJECTIVE

Anterior approaches to the lumbar spine for the treatment of various degenerative or postoperative abnormalities associated with low back pain have always been a matter of debate. They are known to be associated with considerable surgical trauma, high postoperative morbidity, and, occasionally, unacceptably high complication rates. In 1997, we inaugurated two new microsurgical modifications of conventional anterior approach techniques, which have been applied in anterior lumbar interbody fusion and more recently in total disc replacement. This article describes the results of microsurgical anterior interbody fusion in a consecutive series of 171 patients as well as preliminary results of these techniques for total disc replacement in 26 patients.

METHODS

The approaches are performed with the use of a surgical microscope. Lumbar segments L2-L5 are exposed through a lateral retroperitoneal approach. L5-S1 can be reached through a midline retroperitoneal or transperitoneal approach. Both approaches can be performed through a limited skin incision of 4 cm.

RESULTS

An independent observer evaluated results of anterior lumbar interbody fusion in 171 patients during a 2-year follow-up period. The clinical follow-up demonstrated low perioperative and postoperative morbidity with an average blood loss of less than 100 ml at the fusion site. Pseudoarthrosis rates were less than 5%, and clinical results, as evaluated in accordance with the scoring system developed by Prolo et al., did not differ significantly from conventional open techniques. Total disc replacement through a microsurgical anterior approach seems to be a promising alternative to fusion procedures with even less intraoperative and perioperative morbidity.

CONCLUSION

Microsurgical anterior approaches to the lumbar spine provide a reasonable surgical alternative to conventional approaches for anterior interbody fusion and total disc replacement.