Is liquid nitrogen recycled bone and vascular fibula combination the biological reconstruction of choice in lower extremity long bone tumor-related defects?

INTRODUCTION: Combination techniques, which encompass the combined use of vascularized bone grafts with massive allografts or autografts (recycled bone grafts), are especially important in the biological reconstruction of tumor-related lower extremity long bone defects. Liquid nitrogen recycled bone (frozen autograft) and free vascular fibula graft (FVFG) combination, which was coined as the "frozen hotdog (FH)" method by the authors, has not been as widely used nor its outcomes reported for significantly sized patient groups. This study aims to provide an answer to whether FH is a safe and effective reconstructive tool for limb salvage in malignant tumors of the lower extremity regarding radiological, functional, and oncological outcomes. PATIENTS AND METHODS: Sixty-six (male/female: 33/33) patients, who underwent FH reconstruction for tumor-related massive defects of lower extremity long bones between 2006 and 2020, were retrospectively analyzed. The mean age was 15.8 (3.8-46.7) years. The most common tumor localizations were distal femur (42.4%) and proximal tibia (21.2%) while classic osteosarcoma and Ewing's sarcoma were the most common pathologies (60.6% and 22.7%, respectively). Mean resection and FVFG lengths were 160 (90-320) mm and 192 (125-350) mm, respectively. The mean follow-up was 73.9 (24-192) months. RESULTS: The mean MSTS score was 25.4 (15-30) and the mean ISOLS radiographic score was 22.6 (13-24). Mean time to full weight bearing without any assistive devices was 15.4 (6-40) months and the median time was 12 months. MSTS score negatively correlated with resected segment length and vascular fibula length (p < 0.001; p = 0.006). Although full contact apposition of the FH segment correlated with earlier full weight bearing compared to partial apposition (mean 13.7 vs. 17.9 months) (p = 0.042), the quality of reduction did not affect the ISOLS radiographic score at LFU. Overall limb survival rate was 96.3% at 5 and 10 years while FH survival rate was 91.0% and 88.1% at 5 and 10 years. Local recurrence-free survival rates were 88.8% and 85.9%, and overall survival was 89.9% and 86.1% at 5 and 10 years, respectively. Limb length discrepancy was the most common complication with 34 (51.5%) patients while shell nonunion was seen in 21 (31.8%) patients and graft fracture in 6 (9.1%). CONCLUSION: The "FH" method is a safe, effective, and extremely cost-efficient reconstructive tool for tumor-related lower extremity long bone defects. Patient compliance to protracted weight-bearing, ensuring the vitality of the FVFG, and achieving an oncologically safe resection are key factors for a successful outcome.

Mid-term implant survival, functional and radiological results and mechanical complications of mega-prosthetic reconstruction around the knee with the PENTA® system.

AIM: Mega-prosthetic reconstruction is the most common treatment method for massive osteoarticular defects caused by tumor resection around the knee. The new implant is a highly modular rotational-hinged megaprosthesis system with a distinct pentagonal stem geometry and variable implantation options. The aim of this study is to present the mid-term implant survival characteristics, functional and radiological results and mechanical complication profile of the new megaprosthesis. METHODS: One hundred and one mega-prosthetic knee reconstruction procedures in 90 patients (M/F: 51/39) utilizing the new implant system were retrospectively analyzed. In 68 patients, the megaprosthesis was used for primary reconstruction following tumor resection while it was used for revision of other implants in 22. The mean age was 28.5 (7-66) years and the mean follow-up was 59.2 (24-124) months. The most common primary pathology was osteosarcoma with 63-70% patients, the most common anatomical site of involvement was the distal femur with 56-62% patients. RESULTS: Henderson Type 2 failure (aseptic loosening) was seen in only 2-2.2% patients while Type 3 (structural failure) was seen in 29-32.2% Although the 5-year anchorage survival rate was 94.3%, overall mechanical implant survival was 76.1% at 5 years due to a relatively high failure rate in the first-generation hinge mechanism of the implant. The 5-year hinge survival rate demonstrated a significant improvement rate from 61.7% to 87.2% between the first and second generations of the implant (p = 0.027). The mean MSTS score was 24 out of 30 (14-29). The mean cumulative ISOLS radiographic score for index megaprosthesis operations was 19.7 (12-24), which corresponded to excellent outcome. CONCLUSION: The new megaprosthesis system is a reliable choice for the reconstruction of tumor-related massive osteoarticular defects around the knee. Although long-term follow-up is necessary for a definitive evaluation of the implant's survival characteristics, midterm follow-up yields exceptional anchorage properties related to pentagonal stem geometry with very good functional outcomes.

Effect of lengthening speed on the quality of callus and complications in patients with congenital pseudarthrosis of tibia.

PURPOSE: This study aims to evaluate the effect of lengthening speed on the quality of callus and complications during distraction osteogenesis and describe an optimal lengthening speed in patients with congenital pseudarthrosis of tibia (CPT). METHODS: Twenty-seven patients with CPT with a minimum follow-up of 36 months who underwent limb lengthening surgery between 1997 and 2016 with external fixator only were included in this study. All patients underwent lengthening procedures after achieving complete bone union in this study. Regenerate quality is evaluated according to the Li classification on the X-ray taken one month after the end of the distraction period. Complications were noted in post-operative follow-up period. Receiver operator characteristics (ROC) curve analysis was performed to obtain optimal lengthening speed for these patients. RESULT: The mean age at the time of surgery was 5.74 years. The mean lengthening speed was 0.596 mm/day. Follow-up period of 136.14 months with a mean lengthening period of 92.4 days. Mean amount of lengthening was 5.44 cm for patients with CPT. Total rate of callus with good morphological quality was calculated as 66%. According to ROC analysis, optimal cut-off values of lengthening speed for the obtaining good morphological quality callus was 0.564 mm/day for tibial lengthening in CPT. There was a significantly positive correlation between complication rate and lengthening speed for each group. CONCLUSION: We recommend a mean lengthening rate of 0.56mm/day for the lengthening procedures with external fixator in patients with CPT who had complete bone union at the area of pseudarthrosis.

What factors are associated with osteoarthritis after cementation for benign aggressive bone tumor of the knee joint: a systematic review and meta-analysis.

Background: The current systematic review aimed to answer the following questions: (i) Does extended curettage combined with the PMMA technique for the treatment of aggressive bone tumors around the knee led to the development of knee osteoarthritis? (ii) What factors are associated with osteoarthritis after bone cementation around the knee joint? Methods: This study was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. All electronic searches were performed on November 20, 2022, by a single researcher who evaluated the full texts of potentially eligible studies to determine inclusion. In these patients, the presence of osteoarthritis secondary to the surgical procedure was investigated. Data extracted included study type, characteristics of participants, sample size, gender, tumor site (femur or tibia), secondary osteoarthritis, tumor volume, distance from the joint cartilage, reoperation, follow-up time, Campanacci grade, and pathological fracture. Results: In total, 11 studies comprising 204 patients were evaluated, and it was found that 61 (30%) patients developed knee osteoarthritis due to extensive curettage and bone cement application for benign aggressive tumor treatment. According to the results obtained based the random effects model with the 11 studies included in the meta-analysis, the mean odds ratio of development knee OA with the 95% CI was calculated as -2.77 (-3.711, -1.83), which was statistically significant (z = -5.79; P < 0.000). Conclusion: The association of distance between the tumor and joint cartilage and development of osteoarthritis was not shown in this meta-analysis. Level of Evidence: Level IV prognostic study.

Prognostic Factors Influencing Survival and Oncological Outcome in Patients with Parosteal Osteosarcoma.

This study aimed to evaluate the significance of radiological (magnetic resonance imaging [MRI]) findings, surgical, and previous interventions on prognosis with oncological and functional outcome in patients with parosteal osteosarcoma (POS). Twenty-seven patients (8 male/19 female) who were operated with the diagnosis of primary POS in our institution were retrospectively reviewed. The epidemiological data, biopsy method, misdiagnosis/improper interventions, and delay in diagnosis were noted. The lesions' maximum circumferential extension, maximum longitudinal extension, intramedullary involvement, and neurovascular extensions in MRI sections were evaluated, and the resection type (segmental intraarticular/segmental intercalary/hemicortical), reconstruction type (biologic/non-biologic), and surgical margins were noted. Functional and oncological results at the last follow-up were assessed. The mean age was 31.6 (12-73) years, and mean follow-up was 80.8 (24-270) months. Intramedullary involvement percentage was related with maximum circumferential extension percentage and maximum longitudinal extension. (p = 0.006, p = 0.005) The intramedullary involvement ratio of ≤ 10% suggested no recurrence or metastasis. The neurovascular encasement was related to metastatic disease, deep infections, and complication related surgeries (p = 0.017, p = 0.002, p = 0.005). The most common resection type was segmental intraarticular resection (63%). The maximum circumferential extension percentage, the maximum longitudinal extension of the lesion, intramedullary involvement percentage, and neurovascular encasement had lower MSTS scores (p = 0.003, p = 0.028, p = 0.038, p = 0.022). The mean MSTS score was 81.1% (60-100%). The 5-year overall survival was 96.3%, local recurrence-free survival was 77.2%, and metastasis-free survival was 69.4%. The lesions' extent of intramedullary involvement, neurovascular bundle proximity, and maximum periosteal circumferential extension on MRI should be considered when planning the surgery.

Comparative clinical study on deformity correction accuracy of different external fixators.

PURPOSE: In this study, the correction accuracy of Smart Correction spatial fixators and of Ilizarov-type external fixators are compared in terms of deformity complexity. METHODS: Seventy-seven (40 male, 37 female) bone segments of 57 patients treated with a Smart Correction device were compared with 94 (51 male, 43 female) segments of 68 patients treated with an Ilizarov fixator. Mean age of the Smart Correction group was 20.69 ± 12.94 years, and or the Ilizarov group 22.45 ± 12.18 years. Patients were categorised according to limb lengthening and the number of deformity planes. RESULTS: A longer correction period was found with Ilizarov (66.53 ± 47.7 days) compared with Smart Correction (49.05 ± 35.6 days) devices. The bone healing index of the Ilizarov group was significantly better compared with the spatial group. Residual deformity after treatment was significantly lower with the Smart Correction device; however, this relationship could not be shown between subgroups. Although there was no significant difference between subgroups, mean residual deformity was higher with the increasing number of planes of the deformity. CONCLUSIONS: The Smart Correction fixator is an accurate device that allows ease of application and planning. It demonstrates higher accuracy for correcting deformities compared with an Ilizarov external fixator. With an increasing number of planes, the difference between the two devices becomes even more pronounced. The relationship between the complexity of the deformity and residual deformity may possibly be significantly greater in favour of the Smart Correction fixator in a study with a larger sample size.

Treatment of neuropathic unstable knee osteoarthritis by a condylar, rotating-hinge prosthesis with cementless pentagonal stem: a case series.

INTRODUCTION AND IMPORTANCE: Total knee arthroplasty (TKA) in the neuropathic unstable knee (NUK) setting is classically a challenging orthopedic problem due to intraoperative technical difficulties and a higher frequency of periprosthetic complications. More recently, satisfactory results have been reported using improved constraints, stems and revision-type TKA components. The study aims to present long-term results of a small case series with NUK osteoarthritis reconstructed by a condylar, semi-constrained prosthesis with a polygonal, hydroxyapatite-coated (HA-coated) press-fit stem. CASE PRESENTATION: From 2009 through 2010, three knees in three patients with advanced NUK arthropathy underwent TKAs in our institution using the PENTA® prosthesis. The average age at surgery was 44 years (32-58). The patients were followed up for a mean period of 124 months (120-128). The etiology of NUK was determined to be poliomyelitis sequela in 2 cases and spinal cord injury in one case. Functional outcomes were assessed with Knee Society (KS) Knee and Function Scores, and radiological outcomes were evaluated with ISOLS radiographic implant scores. Patients were monitored for complications clinically and radiologically. CLINICAL DISCUSSION: KS knee scores improved from a mean of 12,3 (0-37) preoperatively to 71,3 (65-77) and KS function scores improved from a mean of 1,7 (0-5) preoperatively to 68,3 (55-80) at the latest follow-up. Radiological outcomes were excellent according to ISOLS scores, and no complications were observed. CONCLUSION: Although this is a small case series, the significant improvement in functional scores, excellent radiological outcome, and implant survival at the end of a long follow-up period warrants TKA with a semi-constrained hinged implant in the setting of NUK. PENTA® prosthesis offers a good choice of implant with its hydroxyapatite-coated, press-fit, pentagonal stem and precisely designed rotating hinge.

Femoral Discrepancy After Childhood Bone Sarcoma Surgery Can Be Treated With Magnetic Intramedullary Nails.

This study aims to determine whether femoral lengthening with a magnetic motorized intramedullary nail (PRECICE; NuVasive) is safe and effective in patients with discrepancy due to limb salvage performed for bone sarcomas before skeletal maturity. Six patients (male, 4; female, 2) with a mean age of 9.3 years (range, 4.8-12.8 years) at the time of index limb salvage surgery were retrospectively analyzed. Four patients had undergone biological reconstruction with liquid-nitrogen recycled frozen autograft shell and inlaid vascular fibula combination and 2 had undergone nonbiological reconstruction with distal femur modular tumor endoprosthesis. The mean age at PRECICE operation was 16.1 years (range, 13.4-20.1 years). The mean prelengthening femoral discrepancy was measured as 60 mm (range, 39-80 mm). Lengthening was achieved in 5 of these 6 patients. Although the PRECICE nail was successfully implanted in the sixth patient, lengthening could never be performed owing to failure to overcome the chronic diaphyseal nonunion first, as intended with compressive use of the nail. For the other 5 patients, in whom lengthening was performed, the mean lengthening was 45 mm (range, 35-52 mm), the mean ratio of achieved to planned lengthening was 93% (range, 74%-100%), and the mean bone-healing index was 41 days per cm (range, 24-69 days per cm). Mean Musculoskeletal Tumor Society score improved from 25.6 to 27.2 after lengthening. No major complications occurred. The outcomes of this study demonstrate that the PRECICE implant can safely and effectively correct femoral length discrepancy caused by limb salvage performed for osteosarcoma before skeletal maturity. [Orthopedics. 2023;46(1):27-34.].

Does the technique of limb lengthening affect physeal growth in patient with achondroplasia? Comparison of the simultaneous and consecutive tibia and femur lengthening with external fixators.

We aimed to retrospectively investigate and compare patients who underwent bilateral simultaneous and consecutive lengthening surgery of the femur and tibia in terms of the effect on physeal growth. We hypothesize that compared with the sequential lengthening technique, simultaneous lengthening of the bilateral femur and tibia affects physeal growth to a greater extent. Twenty-six patients with achondroplasia who operated in our clinic between 1995 and 2015 for limb lengthening were included in the study. Fourteen patients with bilateral lengthening of the femur and tibia at the same time were named as simultaneous bilateral lengthening (SBL). Twelve patients with bilateral lengthening of the femur and then bilateral tibia lengthening in other sections or vice versa, at a different time was named consecutive bilateral lengthening (CBL). All patients were followed until at least 18 years old. The physeal arrest was measured with predicted final length at the first visit (investigated with the multiplier method), the total amount of lengthening, and final clinical, and radiological length. Mean limb lengthening was 145 mm (48.5%) and 151 mm (46.6%) for simultaneous and consecutive groups respectively. For lower extremity length, the first group reached 527.6 mm while the expected was 447.3 mm. Considering 151 mm lengthening, the mean growth disturbance for the SBL group was 70.7 mm and for the CBL group was 47.5 mm. For total height comparing between two groups, disturbance for height was 80.5 mm and 65.4 mm, respectively. Although there was no statistical difference, simultaneous bilateral femoral and tibial lengthening has more physiological physeal disturbance effects than consecutive lengthening in patients with achondroplasia.

Is higher body mass index associated with secondary osteoarthritis in patients treated with bone cement for benign aggressive bone tumors? Long-term evaluation of 43 patients.

BACKGROUND: This study was designed to investigate the secondary osteoarthritis rate in patients with benign aggressive bone tumors treated with curettage and cementing at long-term follow up. METHODS: Patients diagnosed with benign aggressive bone tumor (giant cell or aneurysmal bone cyst), treated with extended curettage and cementation with polymethylmethacrylate, who had a minimum of 60 months of follow up after surgery were included in this study. After definitive diagnoses were confirmed by a histopathologist, we decided to perform standard surgical management. Osteoarthritis was staged radiologically using the Kellgren-Lawrence scoring system, and the contralateral knees of the patients were used as the control group. Based on the Kellgren-Lawrence classification system, stages 3 and 4 were accepted as the existence of osteoarthritis. Body mass index, the distance to the subchondral joint line, tumor mass volume, the location of the tumor (i.e., femur, tibia, medial condyle, or lateral condyle), age, and sex were also investigated, all of which are factors that can affect the occurrence of osteoarthritis. RESULTS: Forty-three patients, 24 male (56%) and 19 female (44%), were included in the study. The mean age of the patients was 29.5 ± 10 years, and mean follow up duration was 128.7 months. Tumor localization was the distal femur in 20 patients (46.5%) and the proximal tibia in 23 patients (53.5%). The mean tumor mass volume was 77.84 cm3 and the distance to the knee joint subchondral line was 3.2 ± 2 mm. According to this scoring system, 14 patients were at stage 0, 10 patients were at stage 1, 10 patients were at stage 2, four patients were at stage 3, and five patients were at stage 4. When we compared osteoarthritis development, the affected knee had a significantly higher rate of osteoarthritis development than the contralateral knee. A univariate analysis demonstrated that age (P = 0.002) and body mass index (P = 0.045) were associated with secondary osteoarthritis. Moreover, multivariate analysis demonstrated that none of the variables were independently associated with secondary osteoarthritis. CONCLUSION: Patients with contralateral osteoarthritis had bilateral knee osteoarthritis, indicating that primary osteoarthritis progressed in both knees. Seven of the 43 patients (16.2%) showed secondary osteoarthritis. Although age and body mass index were associated with secondary osteoarthritis in univariate analysis, none of the variables were independently associated with secondary osteoarthritis in the multivariate analysis.

A comparison of external fixation alone or combined with intramedullary nailing in the treatment of segmental tibial defects.

The purpose of this study was to compare the results of external fixation alone versus external fixation combined with intramedullary nailing in the reconstruction of segmental defects of the tibia resulting from chronic osteomyelitis. Thirty-two patients were treated with external fixation alone and 17 patients with the combined technique. Surgical reconstruction utilised distraction osteogenesis by focal segment transport after infection was eradicated. In the external fixation group, the mean size of the defect was 724 cm, external fixation index was 56.32 days/cm and consolidation index was 40.09 day/cm. In the combined technique group, the mean size of the defect was 8.89 cm, external fixation index was 1631 days/cm and consolidation index was 25.7 days/cm. There was no difference in non-union, deformity, limb length discrepancy (LLD), bone and functional results. However, there was a higher rate of reinfection in the combined group when tibial lengthening exceeded 9.25 cm and lengthening ratio was more than 24.8%.

The Relationship Between Limb Lengthening Rate and Callus Quality in Patients with Achondroplasia.

Objectives: This study investigated the effect of the femur, tibia, and humeral lengthening rate in patients with achondroplasia and regenerated bone quality. Methods: The records of the patients with achondroplasia who underwent limb lengthening surgery for both upper and lower extremities between 2002 and 2019 were retrospectively reviewed. Bone formation regeneration was evaluated in each segment at anteroposterior and lateral radiographs and the callus quality was determined at the first month of the consolidation period according to Li's classification system. Results: This study included 42 (28 females and 14 males), 38 (26 females and 12 males), and 17 (11 females and 6 males) patients with bilateral femoral, bilateral tibial, and bilateral humeral lengthening. The mean lengthening rate was 0.920 ± 0.23 (range, 0.53-1.67), 0.813 ± 0.17 (range, 0.51-1.26), and 1.02 ± 0.26 (range, 0.58-150) mm/day in the femoral, tibial, humeral groups, respectively. In the femoral group, 75% femur with good morphological quality, 56.6% good morphological quality in tibial group and 55.9% good morphological quality in humeral group. Statistically significant relationships were found between femoral lengthening rate and callus quality (p < 0.001; r = 0.454). However, no significant correlation was found in the humeral and tibial groups. Moreover, the sensitivity and specificity of the lengthening rate for obtaining good morphological quality callus were 72% and 80%, respectively, with an optimum diagnostic cutoff value of 0.976 mm/day for femoral lengthening. Conclusions: A higher-rate good morphological callus was obtained in femoral lengthening compared with tibia and humerus in patients with achondroplasia.

Comparison of fixator-assisted nailing versus circular external fixator for bone realignment of lower extremity angular deformities in rickets disease.

PURPOSE: In rickets patients, limb deformities are usually multiapical and complex even with medical treatment; residual deformities remain necessitating surgical correction. In our study we aim to compare the results of correction of lower limb deformities, in rickets patients, treated with circular external fixator versus fixator-assisted intra-medullary nail. MATERIALS AND METHODS: Seventeen rickets patients, with 39 deformed lower extremity segments (femur and or tibia), underwent deformity correction procedures in our institution. Ten patients with 26 segments were treated using fixator-assisted nailing. Nine patients with 17 segments were treated using Ilizarov technique with circular frame. All patients were evaluated by long-standing true anteroposterior and lateral orthoroentgenograms of lower extremities preoperatively. Joint alignment, joint orientation, and apices of deformities were calculated and noted. The postoperative results of MAD, MPTA, LDFA, PPPTA and functional criteria were compared with preoperative values and assessments made in SPSS 13.0 for Windows by using McNemar, Pearson Chisquare, and Fisher exact statistical tests. RESULTS: Mean age for the fixator-assisted nailing (FAN) group patients at the time of surgery was 23.8 years (14-37 years). There were 16 femur and 10 tibiae operated on 6 female and 4 male patients. The mean follow up time is 42.6 months (6-71 months). In the Ilizarov group patients the mean age at the time of surgery was 16.7 years (13-22 years). There were 14 tibiae and 3 femur operated on 6 female and 3 male patients. The mean follow-up time was 19 months (6-48 months). Results were evaluated according to the Paley et al. classification of bone and functional results. According to those criteria we had 1 fair, 1 good, and 7 excellent bone results and 1 fair, 1 good, and 7 excellent functional results in the circular ring fixator group. In the FAN group we found 3 good and 7 excellent bone results; 1 fair, 2 good, and 7 excellent functional results. Nearly all patients complained of pain, limping, instability, and walking problems at their first preoperative visit. In both groups there was no union problem; in the FAN group, in one patient correction loss occurred and in another one screw loosening was encountered; in the Ilizarov group, 66% of patients had pin tract infections and one premature fibula consolidation occurred. Statistical analysis revealed no significant difference between two groups in correction ratios.(pearson chi square p = 0.332 for MAD; pearson chi square p = 0.477 for LDFA; Paley functional criteria fisher exact p = 0.684). CONCLUSION: The results indicated that fixator-assisted nailing carries deformity correction accuracy comparable with Ilizarov-type external fixators. FAN provides great patient comfort and the total treatment time is less. In patients with rickets, the retained IM nail can further provide protection against recurrence even if the metabolic pathology reoccurs.

Surgical management of sacral chordoma.

Treatment results of 17 patients who were diagnosed with sacral chordoma between 1993 and 2007, were analyzed retrospectively. The mean duration of symptoms was 30.2 months. The mean tumour size was 10.7 cm; the location was S2 or more proximal in ten-patients. A wide resection was achieved in 14 patients, a marginal resection in one patient and two patients had intralesional excision. Seven patients had a recurrence after a mean time interval of 36.3 months. Wound dehiscence and infection were the major problems. Four patients required continuous urinary catheterization because of incontinence, and ten patients had colostomy or ileostomy simultaneously with tumour resection. This study showed that tumour size and a wide surgical margin are importance factors for survival in chordoma patients. Use of a combined anterior and posterior approach could increase the chance of achieving a wide margin. A multidisciplinary approach is required to achieve this goal.

A review of problems, obstacles and sequelae encountered during femoral lengthening : uniplanar versus circular external fixator.

There is currently a consensus regarding the superiority of circular type external fixators over uniplanar fixators for lengthening of the tibia, but femoral lengthening is still subject to the surgeon's preference. This study compares the occurrence rates of significant problems, obstacles and sequelae between these two techniques. Fifty patients (29 male, 21 female), with a mean age of 20 years were assigned to a circular type fixator group (54 lengthening segments), whereas 60 patients (29 male, 31 female), with a mean age of 20 years were assigned to a uniplanar fixator group (67 lengthening segments). The incidence of knee stiffness was significantly higher in the circular external fixator group (031 per segment) compared to the uniplanar external fixator group (0.13 per segment) (p < 0.05). The incidence of pain during lengthening was higher in the circular external fixator group, and patient satisfaction was higher in the uniplanar external fixator group. We recommend the uniplanar external fixator as a preferable device for femoral lengthening.

Congenital pseudarthrosis of the tibia: Results of circular external fixation treatment with intramedullary rodding and periosteal grafting technique.

OBJECTIVE: This study investigated the clinical and functional results of treating congenital pseudarthrosis of the tibia (CPT) using the combined techniques of hamartoma resection, periosteal grafting, circular external fixator application, and intramedullary rodding. METHODS: The clinical and radiological data of 17 patients (mean age at the treatment time: 7.6 months (range: 4.6-9.7 months) with CPT, treated by a single surgeon between 1997 and 2017, were retrospectively analyzed. All data regarding surgical interventions, complications, deformity analysis parameters, limb length discrepancy (LLD), ankle joint range of motion, and residual deformities were reviewed. All the patients were followed up at least two years after the last surgical intervention. The mean follow-up time was 8.5 years (range: 2.2 to 15.7 years). RESULTS: Union was achieved with the index treatment in 15 of the 17 cases (88.2%). The mean age of the patients at the last follow-up visit was 14.2 years (range: 7.6 to 22.1). The mean LLD was 2.1 cm. Nine patients had radiological ankle valgus at the last follow-up. In the entire series, eight patients did not display any complications, four cases reported minor complications, and five cases were complicated by refractures. CONCLUSION: Circular external fixator application combined with periosteal grafting is a superior method of CPT treatment. This method provides a healthy biological healing environment while correcting the mechanical problems. The combination of periosteal and cancellous bone grafts with intramedullary rods and an external fixator addresses issues that complicate obtaining and maintaining a union during the CPT treatment. LEVEL OF EVIDENCE: Level IV, Therapeutic study.

Treatment of Tibial and Femoral Bone Defects With Bone Transport Over an Intramedullary Nail.

OBJECTIVES: To evaluate the results of the bone transport over an intramedullary nail (BTON) technique for the treatment of segmental bone defects. DESIGN: Retrospective review of case series. SETTING: Level 1 trauma center. PATIENTS/PARTICIPANTS: We included 40 patients who underwent reconstruction of the lower limb with BTON technique between 2000 and 2018. The technique was performed in the tibial segments in 21 patients and in the femoral segments in 19 patients. INTERVENTION: The surgical technique was performed in 2 stages for patients with infected nonunion. Infection was eradicated in all patients at the first stage. For the BTON at the second stage, monolateral external fixators and circular external fixators were used for femoral and tibial defects, respectively. In cases of defects without any infection, debridement with a single-stage BTON was performed. MAIN OUTCOME MEASUREMENTS: Complications as well as radiological and clinical results were evaluated according to the criteria of Paley-Maar. RESULTS: Minor complications occurred in 11 patients: pin site problems (9), cellulitis (1), and skin detachment due to Schanz screw (1). Major complications occurred in 8 patients: docking site nonunion (4), early consolidation and Schanz screw failure (1), knee flexion contracture (1), and ankle equinus contracture (2). Four patients had osteomyelitis as residual sequelae. Bone score was excellent in 27 patients. Excellent functional results were obtained in 31 patients. CONCLUSIONS: The BTON technique is associated with low cost because of the short treatment period, low complication risk, and rapid rehabilitation and is not limited by the amount of bone transport. LEVEL OF EVIDENCE: Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Lengthening of short bones by distraction osteogenesis--results and complications.

We performed bone lengthening surgery on 12 metacarpals and 14 metatarsals of 15 patients. The mean age for metacarpal and metatarsal lengthening was 14.5 (10-21) and 17.5 (10-25) years, respectively. We used a unilateral or a circular external fixator. The mean healing index of the metacarpals and metatarsals was 1.6 (1.1-2.3) and 1.6 (1.0-2.0) months/cm, respectively. The mean increase in metacarpal and metatarsal length was 17.6 (13-26) and 24.3 (20-30) mm, respectively. The functional scores of the metatarso-phalangial (MTP) joint of lengthened metatarsals for the lesser toe were excellent in 12 and good in two cases based on the American Orthopaedic Foot and Ankle Society (AOFAS) scoring system. Complications were seen in six of the metatarsal lengthening cases including four angulations, one subluxation and one non-union. We conclude that the periosteum must be protected with percutaneous osteotomy and lengthening should be performed at a rate of 0.25 mm twice a day and should not exceed 40% of the original bone length (or >20 mm).

Correction of forearm deformities in children with multiple osteochondroma, by corrective radial osteotomy and ulnar lengthening by distraction osteogenesis.

We retrospectively evaluated the results after ulnar lengthening and radial deformity correction using an external fixator for forearm deformities caused by osteochondromas. Eight forearms were treated surgically in seven patients with multiple hereditary osteochondroma. The mean follow-up time was 40 months (range, 20 to 60 months). The average radial articular angle improved from 43 degrees to 35.5 degrees (range, 28 to 56 degrees) and the carpal slip improved from 69.5% to 55% (range, 40 to 60%) postoperatively. The average shortening of the ulna was reduced from 2.06 cm to 0.44 cm (range 0 to 1 cm) after the treatment. There were no serious complications associated with the surgery; two minor pin track infections were successfully treated by local wound care and antibiotics. Although technically demanding, ulnar osteotomy and gradual lengthening by an external fixator provided promising results in the treatment of forearm deformities in children with multiple osteochondroma.

[The effect of resistance-related proteins on the prognosis and survival of patients with osteosarcoma: an immunohistochemical analysis]. / Osteosarkomlu hastalarda dirençle iliskili proteinlerin prognoz ve sagkalim üzerine etkisi: Immünhistokimyasal analiz.

OBJECTIVES: Despite the developments in chemotherapy protocols, improvement in the survival rates of osteosarcoma has been limited. We evaluated the effect of certain prognosis-related proteins on survival of patients with osteosarcoma. METHODS: Data from 45 patients (24 males, 21 females) who were treated and followed-up for osteosarcoma were reviewed. Following neoadjuvant chemotherapy, 41 patients underwent extremity saving surgery, and four patients underwent amputation. The most frequent localization was the lower end of the femur (n=23, 51.1%), followed by the upper end of the tibia (n=10, 22.2%). Three patients had metastasis on admission. Surgical resection samples were retrieved from the pathology archive and analyzed immunohistochemically for the expression of p-glycoprotein p170, p53, heat-shock protein 27 (HSP27), HSP90, and nm23. The effect of these proteins on prognosis and survival was assessed with survival analysis using the Kaplan-Meier method. The mean follow-up was 49.7 months (range 6 to 185 months). RESULTS: Three patients with metastasis on admission died within five years due to pulmonary metastasis. New metastases developed in 29 patients. Total 5-year and 10-year survival rates were 60% and 43%, respectively. The corresponding disease-free survival rates were 41% and 24%. Five-year survival was 29% in patients who developed metastasis. Among clinical factors, survival was influenced only by the presence of metastasis on admission (p=0.044). Five-year and 10-year survival rates were significantly different between patients with and without p53 positivity (p=0.04), while the other proteins were not significantly associated with survival. CONCLUSION: Our data suggest that p53 may be used as a prognostic marker in osteosarcoma due to its significant association with survival.