Marios G. Lykissas

All-pedicle screw versus hybrid instrumentation in adolescent idiopathic scoliosis surgery: a comparative radiographical study with a minimum 2-Year follow-up.

Study Design. Comparative analysis of 2 groups of patients who underwent surgical treatment of adolescent idiopathic scoliosis (AIS). Objective. To compare a segmental pedicle screw only system with a hybrid system for the treatment of Lenke type 1 AIS curves. Summary of Background Data. Although previous AIS studies have tried to compare various constructs with the all-pedicle screw fixation, all have failed to address important confounding variables, such as skeletal maturity, preoperative flexibility of the curve, and factors associated with a multicenter or multisurgeon analysis. Methods. The medical records and spinal radiographs of patients with AIS treated surgically by a single surgeon between 2000 and 2009 were retrospectively reviewed. Patients with Lenke type 1 curves and minimum follow-up of 2 years were divided into 2 groups that were meticulously matched: group 1 consisted of patients in whom the all-pedicle screw construct was used, whereas group 2 included patients who were treated with the hybrid hook-screw system. Results. Group 1 included 34 patients and group 2 included 29 patients. At the last follow-up, thoracic curve correction averaged 70.4% for the all-pedicle screw group and 60% for the hybrid group (P = 0.19). The all-pedicle screw group showed a significantly greater increase in thoracic kyphosis than the hybrid group system (P = 0.04). Global sagittal balance showed greater improvement in the all-pedicle screw group during the immediate postoperative that was lost by the last follow-up. The all-pedicle screw system revealed less intraoperative blood loss but greater operating time than the hybrid construct. After controlling for length of follow-up, no statistical difference in any of the radiographical parameters measured was recorded. Conclusion. With the exception of global sagittal balance, the pedicle screw system provided better maintenance of its corrective parameters when followed for greater than two years. Level of Evidence: 3

Approach to radial nerve palsy caused by humerus shaft fracture: Is primary exploration necessary?

INTRODUCTION While recommendations for early exploration and nerve repair in cases of open fractures of the humeral shaft associated with radial nerve palsy are clear, the therapeutic algorithm for the management of closed humeral shaft fractures complicated by radial nerve palsy is still uncertain. The purpose of this study was to determine whether patients with complete sensory and motor radial nerve palsy following a closed fracture of the humeral shaft should be surgically explored. PATIENTS AND METHODS Twenty-five patients with closed humeral shaft fractures complicated by complete radial nerve palsy were retrospectively reviewed during a 12-year period. Surgical intervention was indicated if functional recovery of the radial nerve was not present after 16 weeks of expectant management. RESULTS Surgical exploration was performed in 12 patients (48%) after a mean period of expectant management of 16.8 weeks (range: 16-18 weeks). In 2 of them (10%) total nerve transection was found. In the rest 10 patients underwent surgical exploration the radial nerve was found to be macroscopically intact. All intact nerves were fully recovered after a mean time of 21.6 weeks (range: 20-24 weeks) post-injury. In 13 patients (52%) in whom surgical exploration was not performed the mean time to full nerve recovery was 12 weeks (range: 7-14 weeks) post-injury. CONCLUSIONS We proposed immediate exploration of the radial nerve in case of open fractures of the humeral shaft, irreducible fractures or unacceptable reduction, associated vascular injuries, radial nerve palsy after manipulation or intractable neurogenic pain. Due to high rate of spontaneous recovery of the radial nerve after closed humeral shaft fractures we recommend 16-18 weeks of expectant management followed by surgical intervention.

Complications of Surgical Treatment of Pediatric Spinal Deformities

Surgery in a child with spinal deformity is challenging. Although current orthopedic practice ensures good long-term surgical results, complications occur. Idiopathic scoliosis represents the most extensively investigated deformity of the pediatric spine. Nonidiopathic deformities of the spine are at higher risk for perioperative and long-term complications, mainly because of underlying comorbidities. A multidisciplinary treatment strategy is helpful to assure optimization of medical conditions before surgery. Awareness of complications that occur during or after spine surgery is essential to avoid a poor outcome and for future surgical decision making. This article summarizes the complications of surgical treatment of the growing spine.

All-Epiphyseal Anterior Cruciate Ligament Reconstruction in Skeletally Immature Patients: A Surgical Technique Using a Split Tibial Tunnel

Many techniques have been described for anterior cruciate ligament (ACL) reconstruction in skeletally immature patients, including extra-articular, complete or partial transphyseal, and physeal-sparing techniques. An all-epiphyseal technique places the tendon and its tunnels and fixation all within the childs epiphysis, leaving the growth plates untouched. We describe an all-epiphyseal quadruple-hamstring ACL reconstruction using a split tibial tunnel. The split tibial tunnels drop the tunnel size down to 4.5 to 5.5 mm from 7 to 8 mm because only half the total graft diameter passes through each of the split tunnels. This increases the safety margin for keeping the tunnel within the tibial epiphysis, in addition to avoiding damage into the growth plate. The bone bridge between the 2 tunnels serves as a solid low-profile fixation post. Femoral graft fixation is achieved with an interference screw, which allows precise tensioning and low-profile fixation entirely within the femoral tunnel. By placing the graft at the native ACLs anatomic attachment points without spanning or violating the growth plates at any step of the procedure, an all-epiphyseal ACL reconstruction with a split tibial tunnel theoretically minimizes the risk of growth disturbance in an ACL-deficient child.

Does the presence of dystrophic features in patients with type 1 neurofibromatosis and spinal deformities increase the risk of surgery

Study Design. Retrospective chart and radiographical review. Objective. To present the demographics of patients with scoliosis and neurofibromatosis type 1 (NF-1), to record the incidence of dystrophic features, and to determine whether the presence of dystrophic features increase the risk of surgery in patients with NF-1 and associated spinal pathology. Summary of Background Data. The most common of the osseous complications of NF-1 is spinal deformity, occurring in 10% to 30% of individuals with NF-1. Many of these patients will eventually require surgery for curve progression, which makes study of demographics and identification of features predicting the need for surgery essential in this patient population. Methods. A retrospective review was performed in patients with NF-1 and spinal deformities, followed in a multidisciplinary neurofibromatosis center. A subset of 56 patients with complete radiographical evaluation was reviewed for identification of risk factors for spine surgery. Results. One hundred thirty-one patients from a population of 694 patients with NF-1 (19%) had scoliosis. Mean age at diagnosis of scoliosis was 9 years (range; 1–17 yr). Scoliosis and need for surgery were equally distributed between males and females. In the group of 56 patients, 63% had 3 or more dystrophic features. The presence of 3 or more dystrophic features was the strongest predictor of the need for surgery (odds ratio = 14.34; P < 0.001). Individual features most predictive of need for surgery were the presence of vertebral scalloping (odds ratio = 13.19; P < 0.001) followed by the presence of dural ectasia (odds ratio = 6.38; P = 0.005). Patients with no dystrophic features were unlikely to progress to need for surgery. Conclusion. Scoliosis and need for surgery were equally distributed between males and females. The presence of 3 or more dystrophic features was highly predictive of the need for surgery, with the most significant individual predictors being vertebral scalloping and dural ectasia. A combination of radiographical and MRI features can be used to predict need for spinal surgery. Level of Evidence: 3

The role of hypercoagulability in the development of osteonecrosis of the femoral head.

Despite the large number of the outstanding researches, pathogenesis of osteonecrosis remains unknown. During the last decades the hypothesis that increased intravascular coagulation may be the pathogenetic mechanism which leads to osteonecrosis is gaining constantly support. Both primary factors of hyper-coagulability, such as resistance to activated protein C, protein C and protein S deficiency, low levels of tissue plasminogen activator, high levels of plasminogen activator inhibitor, von Willebrand factor, lipoprotein (a), and secondary factors of hypercoagulability with factors potentially activating intravascular coagulation, such as pregnancy, antiphospholipid antibodies, systemic lupus erythematosus, hemoglobinopathies and sickle cell disease, and hemato-oncologic diseases are discussed in this article. Although coagulation abnormalities in patients with hip osteonecrosis might represent increased risk factors for the development of bone necrosis by predisposing the patient to thromboembolic phenomena, further investigation is needed to indicate the definite correlation between factors leading to increased intravascular coagulation and pathogenesis of osteonecrosis.

Transient cortical blindness as a complication of posterior spinal surgery in a pediatric patient.

Postoperative vision loss after spinal surgery is a well-known but devastating complication that may result from direct ocular ischemia, embolism to the central retinal artery, ischemic optic neuropathy, or occipital cortical ischemia. The occipital cortex is situated in the posterior border zone of the middle and posterior cerebral arteries and is susceptible to ischemic damage. Transient cortical blindness as a cause of postoperative vision loss has never been reported after spine surgery in a child. We report an 11-year-old female patient with muscular dystrophy who underwent posterior spinal fusion and instrumentation under hypotensive anesthesia for scoliosis who developed transient cortical blindness.

Is there any relation between the amount of curve correction and postoperative neurological deficit or pain in patients undergoing standalone lateral lumbar interbody fusion

Study Design. Retrospective analysis of 73 standalone lateral lumbar interbody fusion (LLIF) procedures to identify any association between the amount of coronal curve correction and lumbosacral plexus injuries and/or postoperative pain. Objective. To address if there is any association between the amount of correction in both the coronal and sagittal planes and the development of postoperative neurological deficit and/or anterior thigh/groin pain. Summary of Background Data. LLIF is a powerful tool for the restoration of spinal alignment including correction of small degenerative curves of the lumbar spine and increase of lumbar lordosis. Concerns remain about its safety regarding injuries of the lumbosacral plexus, which occur with a prevalence ranging from 0.7% to 23%. Methods. The medical records and spinal radiographs of patients undergoing standalone LLIF for symptomatic degenerative scoliosis of the lumbar spine were retrospectively reviewed during a 6-year period. Results. Thirty patients (73 levels) met the inclusion criteria and were followed for a mean of 21 months (range, 9–39 mo). Average age at the time of surgery was 67 years (range, 50–78 yr). Immediately after surgery, a motor deficit was recorded in 6 patients and a sensory deficit in 17 patients. Statistical analysis did not reveal any significant association between the amount of coronal curve correction, restoration of lumbar lordosis or increase in lumbar spine height, and the development of postoperative motor or sensory deficits. Seventeen patients complained of anterior thigh/groin pain immediately postoperative. A statistically significant association was identified between postoperative anterior thigh/groin pain and the magnitude of curve correction (P = 0.005), as well as the increase in lumbar lordosis (P = 0.040). Conclusion. There is a strong association between the development of postoperative anterior thigh/groin pain and the amount of coronal curve correction, as well as the increase in lumbar lordosis. Level of Evidence: 4

Growth Stimulation Following an All-Epiphyseal Anterior Cruciate Ligament Reconstruction in a Child

Over the past decade, there has been a substantial increase in the number of reported intrasubstance tears of the anterior cruciate ligament (ACL) in children younger than twelve years of age or in prepubescent children1-6. Multiple studies have emphasized the need for early ACL reconstruction in skeletally immature patients to prevent the development of meniscal tears and early knee arthrosis7-10. The native ACL in children always courses from the distal femoral epiphysis to the proximal tibial epiphysis. If the usual ACL reconstruction used in adults is performed on a child or adolescent, this anatomy becomes problematic because tunnels are drilled through the growth plates into the distal part of the femur and the proximal tibial metaphyses. In children with wide-open growth plates, a solidly fixed and tensioned graft, placed as in adults, may potentially cause a “tether effect” that can retard growth at these growth plates11,12. In order to avoid tether or bone-bar formation, multiple partial or complete physeal-sparing techniques to reconstruct the ACL in this age group have been proposed1,6,13-16. Growth disturbance, especially growth arrest, has been a major concern with the surgical management of intrasubstance ACL tears in growing children and adolescents12,15,17-20. In contrast, limb overgrowth is a theoretical possibility following any long-bone surgery in a child. To our knowledge, there are no reported cases of clinically significant limb overgrowth that required surgical epiphysiodesis as a consequence of a physeal-sparing or an all-epiphyseal ACL reconstruction in a child. This case is reported to alert physicians, patients, and their parents that overgrowth requiring surgical correction can occur after ACL reconstruction in a skeletally immature child. The patient and his parents were …

Challenges of spine surgery in patients with chondrodysplasia punctata.

Background: Chondrodysplasia punctata (CDP) is a common manifestation of an etiologically heterogenous group of disorders. There is very little data regarding the development and management of spinal deformity in patients with CDP. The purpose of this study was to present a multicenter series of CDP, to describe the surgical outcomes of spinal deformities in CDP patients and to emphasize important considerations that may influence choice of surgical treatment of spinal deformity in this patient population. Methods: The medical records and spinal radiographs of patients with the diagnosis of CDP followed in 2 centers between 1975 and 2011 were retrospectively reviewed. Epiphyseal stippling was present on radiographs in all patients who fulfilled the clinical criteria. Results: Among the 17 patients who were diagnosed with CDP, 13 had spinal deformities. The mean age at diagnosis of spinal deformity was 14.6 months (range, 1 wk to 9 y). Males and females were close to equally represented (10 males and 7 females). Twelve patients (92%) required surgery to correct spinal deformity. Patients were followed for a median of 8.4 years (range, 2.8 to 19.5 y). The total number of surgical procedures performed was 17 averaging 1.5 per patient. Four patients required >1 procedure. Eighty percent of the patients who required >1 surgical procedure were females with probable diagnosis of X-linked dominant CDP. Revision surgery was indicated in 50% of the patients treated with combined anterior and posterior fusion and 20% of the patients treated with posterior fusion alone. Conclusions: Spinal deformity in CPD patients may range from significant kyphoscoliosis to minimal deformity that does not require any treatment. For those patients in whom spine surgery was indicated, a high incidence of revision surgery and curve progression after fusion was recorded. Female patients with probable diagnosis of X-linked dominant CDP were more likely to require a second surgical procedure. Isolated posterior fusion showed less favorable results compared with combined anteroposterior fusion in terms of revision surgery. Level of Evidence: Level IV—therapeutic study.