Guney Yilmaz

Comparative analysis of hook, hybrid, and pedicle screw instrumentation in the posterior treatment of adolescent idiopathic scoliosis.

Background: Spinal instrumentation in adolescent idiopathic scoliosis (AIS) aims to correct spinal deformity and maintain long-term spinal stability until bony healing is ensured. The purpose of this study was to compare the minimum 2-year postoperative radiographic and clinical results of posterior spine correction and fusion with all-hook instrumentation versus hybrid segmental instrumentation versus pedicle screw instrumentation for AIS from a single institution. Methods: A total of 105 patients with AIS who underwent a posterior spinal fusion with segmental pedicle screw (35), hook (35), or hybrid (35) instrumentation were sorted and matched according to the following criteria: similar age at surgery, identical Lenke curve types, curve magnitude, and Risser grade. Patients were evaluated before, immediately after, and at 2 years after surgery for radiographic parameters, complications, and outcome, as well as on the basis of the Scoliosis Research Society (SRS) questionnaire. Results: The age and Risser grade, major curve Cobb angle, apical vertebral rotation (AVR), apical vertebral translation (AVT), lowest instrumented vertebral tilt, global coronal and sagittal balance, lumbar lordosis, and thoracic kyphosis were determined as part of preoperative evaluation. All 3 groups showed significant differences between the preoperative and postoperative major curve Cobb angle, lowest instrumented vertebral tilt, AVT, and AVR. At the latest follow-up, lumbar lordosis, thoracic kyphosis, and global coronal and sagittal balance remained similar among the 3 groups. Major curve Cobb angle, AVT, and AVR were significantly different—the hook group’s measurements were significantly higher than the other groups, but there was no difference between the pedicle screw and hybrid groups. Major curve correction rate was significantly different among all groups (screw=71.9%±13.8%, hybrid=61.4%±16.6%, hook=48.1%±19.7%) (P<0.001). The pedicle screw group had the least amount of correction loss but there was no statistically significant difference between groups (screw=2.6±6.7 degrees, hybrid=4.5±7.4 degrees, hook=4.4±6.2 degrees) (P=0.35). The hook group had the least amount of AVT correction, but the screw group and the hybrid groups were similar (pedicle=67.3%±15.5%, hybrid=57.5%±22.4%, hook=39.9%±32.5%) (P<0.001). Surgery time and blood loss were higher in the screw group. No differences in global SRS-22 scores were demonstrated between the patients treated with pedicle screw, hybrid, and hook constructs; however, the satisfaction domain was higher in the screw group at the latest follow-up. Conclusions: Pedicle screw and hybrid instrumentations offer significantly better spinal deformity correction than hook constructs in major curve coronal correction, AVT, and AVR. Patients with pedicle screw instrumentation had the greatest curve correction percentage, maintenance of this correction in the coronal and sagittal planes, and higher patient satisfaction by the SRS outcome scores. Global SRS-22 scores were similar at 2-year follow-up in all groups. Level of Evidence: Therapeutic level III retrospective comparative study.

Correction of lower extremity angular deformities in skeletal dysplasia with hemiepiphysiodesis: a preliminary report.

Background: Lower extremity angular deformities are common in children with skeletal dysplasia and can be treated with various surgical options. Both acute correction by osteotomy with internal fixation and gradual correction by external fixation have been used with acceptable results. Recently, the Guided Growth concept using temporary hemiepiphysiodesis for correction of angular deformities in the growing child has been proposed. This study presents the results of temporary hemiepiphysiodesis using eight-Plates and medial malleolus transphyseal screws in children with skeletal dysplasia with lower extremity angular deformities. Methods: Twenty-nine patients (50 lower extremities) with skeletal dysplasia of different types were treated for varus or valgus deformities at 2 centers. The mean age at the time of hemiepiphysiodesis was 10±2.9 years. A total of 66 eight-Plates and 12 medial malleolus screws were used. The average follow-up time between the index surgery and the latest follow-up with the eight-Plate in was 25±13.4 months. Erect long-standing anteroposterior and lateral view radiographs were obtained for deformity planning before the procedure. Angular deformities on radiograph were evaluated by mechanical axis deviation, mechanical lateral distal femoral angle, medial proximal tibial angle, and lateral distal tibial angle. Mechanical axis deviation was also expressed as a percentage to one half of the width of the tibial plateau, and the magnitude of the deformity was classified by determining the zones through which the mechanical axis of the lower extremity passed. Four zones were determined on both the medial and lateral side of the knee and the zones were labeled 1, 2, 3, and 4, corresponding to the severity of the deformity. A positive value was assigned for valgus alignment and a negative for varus alignment. Results: Patients were analyzed in valgus and varus groups. There was correction in 34 of 38 valgus legs and 7 of 12 varus legs. In the valgus group, the mean preoperative and postoperative mechanical lateral distal femoral angles were 82.1±3.7 and 91.1±4.9 degrees, respectively (P<0.001). The mean preoperative and postoperative medial proximal tibial angles were 98.5±8 and 87.8±7.1 degrees, respectively (P<0.001). Six patients with bilateral ankle valgus deformities (12 ankles) underwent single-screw medial malleolus hemiepiphysiodesis. The mean preoperative and postoperative lateral distal tibial angles were 73.9±8.7 and 86.1±6.8 degrees, respectively (P<0.001). The numbers of plates in each anatomic location were not enough to make statistical conclusions in varus legs. Four patients in the valgus group and 3 patients in the varus group did not benefit from the procedure. Mechanical axes were in zone 2 or over in 94% of the legs preoperatively, whereas postoperatively, only 23% of the legs had mechanical axes in zone 2 or over in varus and valgus groups. Conclusions: Growth modulation with an eight-Plate is a relatively simple surgery and has low risk of mechanical failure or physeal damage. It can be performed in very young patients, which is an important advantage in skeletal dysplasia. Screw purchase is reliable even in the abnormal epiphysis and metaphysis. Our results show that Guided Growth using eight-Plates in skeletal dysplasia is safe and effective. Level of Evidence: Level IV.

The effect of posterior distraction on vertebral growth in immature pigs: an experimental simulation of growing rod technique.

Study Design. Experimental study. Objective. The aim of this study is to evaluate the vertebral body growth under distraction forces in immature pigs treated with growing rod (GR) technique. Summary of Background Data. Distraction forces applied on growth plate of appendicular skeleton stimulate longitudinal growth. However, the effect of distraction forces on axial skeletal growth has not been fully investigated yet. Methods. Twelve 10-week-old domestic pigs were used in this experimental model to simulate GR technique. Four of them were lost during postoperative period because of deep wound infection. Cranially T12–L1 and caudally L4–L5 vertebrae were instrumented by pedicle screws bilaterally, while L2 and L3 were skipped. Distraction between pedicle screws was applied at index surgery. The rods were then lengthened twice in a month interval. All subjects were evaluated with anteroposterior and lateral spinal radiograph before surgery, after surgery, and at the final follow-up. The vertebral body heights of distracted segments (HD = L2 and L3) and control segments (HC = T9, T10 and T11) were measured. Average vertebral body heights and the increase percentage in the vertebral body heights were compared among control segments and distracted segments. Results. The preoperative vertebral body height was similar in 2 groups (preHC: 10.81 mm, n = 19, preHD: 11.27 mm, n = 16, P > 0.05). At the final follow-up, the average vertebral body height in distraction group was significantly higher than the control group (postHC: 17.03 mm, postHD: 18.58 mm, P < 0.05). The increase percentage in vertebral body height was higher in distracted segments, but there was no statistically significant difference between the 2 groups. Conclusion. The vertebral growth continues during GR instrumentation. Distraction forces might stimulate also apophyseal growth of axial skeleton.

Intraneural hemangioma of digital nerve diagnosed with MR imaging

Hemangioma may occur at any location. Although the imaging findings of hemangioma are well known, it may be difficult to differentiate this entity from other soft-tissue tumors. Intraneural hemangiomas are extremely rare. We present a girl with a painful swelling in the fourth web space of her right hand. Since it was painful, the referring clinician considered the possibility of a glomus tumor. However, demonstration of dilated feeding or draining vessels suggested the diagnosis of hemangioma. At surgery a hemangioma of the ulnar digital nerve of the ring finger was resected marginally.

Surgical treatment of scoliosis in osteogenesis imperfecta with cement-augmented pedicle screw instrumentation.

Study Design: A retrospective study. Objective: To report the early postoperative results of scoliosis surgery in osteogenesis imperfecta (OI) patients utilizing all pedicle screw constructs and present a novel cementing technique to increase pedicle screw purchase in the osteoporotic OI spine. Summary of Background Data: Scoliosis surgery utilizing hooks and wire systems have high complication rates in OI. Pedicle screw fixation systems have the biomechanical advantage of 3-column fixation, and cement augmentation of pedicle screws provides additional pull-out strength in the osteoporotic OI spine. Methods: The clinical and radiologic results of 10 consecutive OI patients treated with all pedicle screw instrumentation and fusion were retrospectively reviewed. The radiologic data included preoperative and postoperative major curve measurements: major curve Cobb angle, global coronal balance (GCB), apical vertebral translation (AVT), and the lowest instrumented vertebral (LIV) tilt. Operative findings included blood loss, surgery time, and additional procedures. All patients received intravenous pamidronate therapy preoperatively to increase bone mineral density. Results: Ten patients with OI were operated on between 2005 and 2009. Seven had cement-augmented pedicle screw insertion at the proximal and distal foundations. The mean hospital stay was 10±7.5 days (range, 4–27 d) and the average follow-up period was 25.7±13.1 months (range, 14–50 mo). Mean preoperative and postoperative major Cobb angles were 83.7±23.8 and 40.3±14.6 degrees, respectively (48% correction; P<0.05). Mean preoperative and postoperative GCB deviations were 26.7±18.6 and 14.1±13.3 mm, respectively (P=0.097). Mean preoperative and postoperative AVTs were 69.3±29.1 and 29±12.2 mm, respectively (P<0.05). Preoperative and postoperative LIV tilts were 18.5±8.9 and 5.2±3.9 degrees, respectively (P<0.05). At the latest follow-up, the mean major curve Cobb angle was 37.7±13.1 degrees, the GCB deviation was 13.8±5.1 mm, the AVT was 31.7±13.3 mm, and the LIV tilt was 11.3±8.8 degrees. There was no difference between the early postoperative and the latest follow-up major curve Cobb angle, GCB deviation, AVT, or LIV tilt, indicating maintenance of correction. The mean blood loss was 23,75 mL (range, 800–45,00 mL). The mean operative time was 375.4 minutes (range, 262–491 min). The mean postoperative Scoliosis Research Society-22 patient-based outcome scores were 4.6±0.7 (out of 5). There were no instrumentation failures or permanent neurological deficits in this series. Conclusions: Pedicle screw instrumentation in OI scoliosis is safe and effective. Cement augmentation in these patients may help to increase the pedicle pull-out strength and decrease the screw failure rates, especially at the proximal and the distal ends of instrumentation.

Safety and efficacy of instrumented convex growth arrest in treatment of congenital scoliosis.

Background: Anterior and posterior convex hemiepiphysiodesis is a widely used surgical alternative in the treatment of congenital scoliosis. This procedure has the disadvantage of the need for both anterior and posterior approaches. Furthermore, outcomes may be unpredictable. Posterior convex growth arrest (CGA) with pedicle screws at each segment on the convex side may obviate the need for anterior surgery and provides more predictable outcomes. This study retrospectively evaluates the safety and efficacy of instrumented posterior CGA in congenital scoliosis. Methods: Patients who had posterior CGA with convex pedicle screw instrumentation for congenital scoliosis were evaluated retrospectively. Thirteen patients (6 male, 7 female) were included in the study. Preoperative, early postoperative, and last follow-up standing posteroanterior and lateral x-rays were evaluated. Cobb angles were recorded for the instrumented segment (main curve). Global thoracic kyphosis was measured between T2 and T12 on sagittal plane. These values were compared preoperatively, postoperatively, and at last follow-up. The T1-S1 vertical height and the height between the concave side pedicles of the upper and lower end vertebra of the main curve was also determined and recorded as the concave height. Results: The average follow-up was 56.1±10 months (range, 36 to 74 mo) and the average age of the patients at the time of operation was 64.5±30.1 months (range, 15 to 108 mo). All patients were Risser zero at the time of surgery. The average curve magnitude was 49±10.9 degrees (range, 34 to 68 degrees) preoperatively, 38.3±9.7 degrees (range, 28 to 58 degrees) early postoperatively, and 33.5±12.4 degrees (16 to 52 degrees) at last follow-up. There was a significant difference between the preoperative and early postoperative main curve Cobb angle measurements (P=0.001). The average concave height was 94.2±20.2 mm in the early postoperative period and 104.7±21.7 mm at last follow-up (P=0.003). The average T1-S1 height was 292.1±67.1 mm in the early postoperative period and 363.9±94.5 mm at last follow-up (P=0.005). There was at least ≥5 degrees improvement in 9 of the 12 patients in the follow-up period after the index procedure. In 3 patients, the curve did not change and the correction was maintained. Curve progression was observed in 1 patient due to a technical error. There were no wound infections or instrumentation failures during follow-up. Conclusions: Instrumented CGA can safely be used in long sweeping curves of immature spines. Using this technique; thoracotomy, anterior procedure, and 2-stage surgery can be avoided. Moreover, it guarantees some degree of correction in all patients because of the instrumentation effect, eliminating the unpredictable nature of classic CGA. Level of Evidence: Therapeutic level IV study.

Subtalar fusion in cerebral palsy patients: results of a new technique using corticocancellous allograft.

Background Valgus deformity of the hindfoot in cerebral palsy (CP) patients is common and causes functional deterioration and shoe fitting problems together with skin ulcerations. Our aims in this study are, to present an intra-articular technique of subtalar fusion using allograft and internal fixation to achieve stabilization and second to report the results and clinical outcome of a series of intra-articular subtalar arthrodesis performed in CP children. Methods We performed a retrospective review of radiographs and medical records of 145 children with CP who underwent intra-articular subtalar fusion from January 1994 to December 2004. The subtalar joint was fixed through the anterior facet with a cannulated screw whereas the anterior aspect of the calcaneus was parallel to the anterior aspect of the head of the talus. Tricortical iliac crest allograft was placed into the sinus tarsi and the denuded posterior facet area. Results are grouped as good, satisfactory, and poor according to the radiographic and clinical outcomes. Results The mean age at the time of surgery was 12.7 years (range: 5 to 20 y) and the average follow-up was 4.8 years (range: 2 to 11 y). Good results were obtained in 242 feet (96%). Satisfactory results were obtained in 6 feet (2%) which were painless pseudoarthrosis of subtalar joint in 2 feet and screw removal was required in 4 feet because of pain. Nonunion of thesubtalar joint together with recurrence of deformity was observed in 5 feet (2%) which is accepted as poor result and required revision surgery. No deep infections, implant failure, allograft failure were observed in a mean of 4.8 years. Conclusions Our described technique of intra-articular subtalar joint fusion is safe and reliable in CP children with high rate of satisfactory results. Level of Evidence Therapeutic studies-Level IV.

Reconstruction of multiple fingertip injuries with reverse flow homodigital flap

AIM Hand trauma may lead to multiple fingertip defects, causing functional restrictions. We evaluated the use of reverse-flow homodigital flap reconstruction of the distal phalanx and pulp defects associated with multiple finger injuries. METHODS We retrospectively evaluated 11 male patients who presented at our emergency department (January 2011-March 2013) with multiple fingertip injuries and who were treated with a reverse-flow homodigital flap. Evaluations included age, sex, defect size, flap survival rate, complications, cold intolerance, two-point discrimination, range of motion (ROM), quick disabilities of the arm, shoulder, and hand (DASH) score, and return to work time. RESULTS Completely, 22 reverse-flow homodigital flaps were applied to at least two fingertip injuries at the distal phalanx. Ten flaps survived postoperatively. The exception was partial flap loss on one finger. The mean follow-up was 14.2 months. At the final follow-up, the mean static two-point discrimination value was 10.3mm. Mean ROMs of interphalangeal joints were 65.31° (distal) and 105.77° (proximal). Donor sites were covered with full-thickness skin grafts from the wrist or antecubital area. There were no complications related to the donor site and no development of cold intolerance in any finger. The mean quick DASH score was 4.12. All patients returned to work in an average of 8.3 weeks. CONCLUSIONS The reconstruction of multiple fingertip injuries with reverse-flow homodigital flaps is a safe, effective method that can be combined with other local finger flaps. These flaps can be applied to two consecutive fingers without reducing finger length or function.

Long-term outcome and quality of life of patients with unstable pelvic fractures treated by closed reduction and percutaneous fixation.

BACKGROUND Treatment of unstable pelvic fractures has evolved recently, and percutaneous treatment has become the choice of treatment in most cases. The aim of this study was to evaluate the outcome of percutaneous treatment in patients with unstable pelvic fractures. METHODS Twenty patients (11 females, 9 males; mean age, 32 years, range, 11-66 years) who had unstable pelvic fractures and were treated percutaneously were enrolled in the study. Short Form-36 (SF-36) scores, Majeed scores, Iowa Pelvic Scores, and Pelvic Outcome Scores were determined for the outcome assessment. RESULTS The minimum duration of follow-up was 2 years, (range, 24-48 months). The mean Injury Severity Score (ISS) was 31 (range, 16-50). The average SF-36 scores were comparable with the general population in terms of bodily pain, general health and social function. The mean Majeed functional pelvic score was 93.3 (range, 72-100; 19 excellent and 1 good clinical grades) and the mean Iowa Pelvic Score was 86 (range, 82-90). The mean Pelvic Outcome Score was 33 (range, 24-37; maximum score, 40). CONCLUSION We have demonstrated better outcomes in patients with pelvic fractures treated with percutaneous fixation. The technique may be advantageous as it avoids the use of extensive approaches, bleeding, wound complications, and prolonged surgeries.

The effect of anterior spinal fusion on spinal canal development in an immature porcine model.

Study Design. Experimental study. Objective. To investigate whether anterior spine fusion in the immature porcine spine has an adverse effect on the development of spinal canal. Summary of Background Data. Neurocentral cartilage (NCC) is located in the posterior vertebral body and responsible for the development of posterior aspect of the spinal canal. Injury to the NCC interferes with the development of the spinal canal. Methods. Twelve 8-week-old domestic pigs were used to develop an anterior fusion model. A standard procedure as L3–L4, L4–L5 discectomy, and L3–L5 anterior instrumented spine fusion was performed. To evaluate the development of the spinal canal, all subjects had computed tomography scans before the procedure and at the final follow-up. The spinal canal area was measured at the control level (CL) (L2), arthrodesis level (AL) (L4), superior (L3), and inferior (L5) instrumented level (SIL and IIL). Percent change in spinal canal area from before surgery to final follow-up was also calculated. Results. Eleven subjects were available for the study. All subjects developed local kyphosis over the fused segments. The average area of L2 (CL) was 0.56 ± 0.06 cm2 before surgery. The average areas of the L3 (SIL), L4 (AL), and L5 (IIL) were 0.62, 0.70, and 0.77 cm2, respectively. At the final follow-up the average area of L2 was 1.20 cm2. The average areas of the SIL, AL, and IIL were 1.16, 1.19, and 1.33 cm2, respectively. The percent increase in spinal canal area at the CL was 116.6% whereas it was 85.8%, 71.0%, and 71.2% at SIL, AL, and IIL, respectively. Conclusion. Anterior spinal arthrodesis in the immature porcine spine results in iatrogenic retardation on spinal canal growth. This effect is most likely related to the tethering effect of the interbody fusion over the NCC. Although, it is difficult to directly extrapolate these findings to clinical practice, the spine surgeons operating on pediatric patients should be aware of this possibility.