[Surgical Treatment of Tuberculous Spondylodiscitis]. / Operacní lécba tuberkulózní spondylodiscitidy.

PURPOSE OF THE STUDY The paper presents a monocentric retrospective study of patients treated surgically for spinal tuberculosis. Clinical and radiological results are analysed, early and late complications are recorded. The study aims to answer the following questions. 1. Can we use instrumentation to restore the stability and alignment in the infected spinal focus? 2. Should we always perform radical anterior resection of TBC lesions? 3. What is the prognosis of surgical treatment of TBC patients with neurological deficit manifestation? MATERIAL AND METHODS Between 2010 and 2020, a total of 12 patients were treated for spinal tuberculosis at our department, of whom 9 patients (5 men, 4 women) with the mean age of 47.3 years (range 29 to 83 years) underwent a surgery. A total of three patients were operated on before the final confirmation of the TBC and treatment with antituberculosis medication, four patients in the initial therapy phase and two patients in the continuous phase. Two patients only underwent a non-instrumented decompression surgery followed by external support fixation. In the other seven patients, always with spinal deformity, instrumentation was used (3 cases of isolated posterior decompression, transpedicular fixation, posterior fusion, 4 cases of anteroposterior instrumented reconstruction). In 2 cases a structural bone graft and in 2 cases an expandable titanium cage were used for anterior column reconstruction. RESULTS Of the total number of patients, altogether eight patients were assessed at 1 year after surgery (one 83-year-old patient died from heart failure 4 months after surgery). Of the remaining eight patients, three patients exhibited a neurological deficit and postoperative regression of the finding. The McCormick score improved from the preoperative mean score of 3.25 to 1.62 at 1 year after surgery (p < 0.001). The clinical VAS score regressed from 5.75 to 1.63 at 1 year after surgery (p < 0.001). Radiographic healing of the anterior fusion was achieved in all patients, both after decompression and instrumented surgery. The initial mean kyphosis of 20.36 degrees of the operated segment measured by the mCobb angle was corrected to 14.6 degrees postoperatively, with a subsequent slight deterioration to 14.86 degrees (p < 0.05). The greatest correction was achieved in patients who had undergone a two-stage surgery with anterior resection and AP reconstruction. DISCUSSION In our cohort, titanium instrumentation was used in seven of nine patients. One patient only manifested persistent tuberculosis with nonspecific bacterial flora superinfection. Revision surgery with anterior radical debridement and subsequent treatment with antituberculotic drugs healed the patient. There were four patients with major preoperative neurological deficit persisting more than 2 weeks before the final treatment with subsequent improvement in all cases. These patients were treated with anteroposterior reconstruction and anterior radical debridement. CONCLUSIONS No increased risk of recurrent infection associated with the use of spinal instrumentation was found in the study. Anterior radical debridement is performed in patients with manifested kyphotic deformity and spinal canal compression, followed by reconstruction with a structural bone graft or a titanium cage. The other patients are treated based on the principle of "optimal" debridement with or without the use of transpedicular instrumentation. If adequate spinal canal decompression and stability are achieved, neurological improvement can be anticipated even in case of a major neurological deficit. Key words: spine tuberculosis, tuberculous spondylitis, Pott's disease, anterior debridement, spine instrumentation.

[Modified Harrington Procedure in the Treatment of Extensive Tumor Defects of the Acetabulum]. / Modifikovaná Harringtonova operace v terapii rozsáhlých nádorových defektu acetabula.

PURPOSE OF THE STUDY The increasing prevalance of patients with metastatic bone cancer and their improved survival puts more emphasis on the quality of treatment of bone metastases. Although most pelvic lesions are treated non-operatively, extensive destruction of the acetabular segment poses a therapeutic challenge. A potential treatment option may be the modified Harrington procedure. MATERIAL AND METHODS At our department, this surgical procedure has been opted for in 14 patients (5 men and 9 women) since 2018. The mean age at the time of surgery was 59 years (range 42 to 73). Twelve patients suffered from metastatic cancer, one patient had a fibrosarcoma metastasis and one female patient presented with aggressive pseudotumor. Radiological and clinical followup of the patients was performed. Pain was assessed using the Visual Analogue Scale, and the Harris Hip Score and the MSTS score were used to evaluate the functional outcome. The paired samples Wilcoxon test was used to analyze the statistical significance of the difference. RESULTS The mean follow-up period was 25 months. At the time of assessment, ten patients were alive with the mean follow-up of 29 months (range 2 to 54 months) and four patients had died of cancer progression, with the mean follow-up being 16 months. No perioperative death or mechanical failure were reported. One female patient developed a hematogenous infection during febrile neutropenia, which was successfully managed with early revision and implant preservation. Statistically, a significant improvement in the MSTS (median 23) and HHS (median 86) functional scores compared to the preoperative values (MSTS median 2, p<0.01, r-effect size = 0.6; HHS preop median 0, p<0.005, r-effect size = -0.7) was observed. There was also a statistically significant reduction in pain (VAS postoperative median 1, VAS preoperative median 8, p<0.01, r-effect size = -0.6). All patients were capable of independent ambulation after the surgery, nine patients walked without support. DISCUSSION There are not many alternatives to this surgical procedure. Apart from non-operative palliative treatment, the options include ice cream cone prostheses or customized 3D implants which are, impractical in terms of time and cost. Our results are comparable to other studies, confirming the reproducibility and reliability of the method. CONCLUSIONS The Harrington procedure is an efective method for management of large acetabular tumor defects with good functional outcomes, an acceptable perioperative risk and a low risk of failure in the medium term, thus suitable also for patients with good cancer prognosis. Key words: umor, metastasis, acetabulum, pelvis, Harrington, reconstruction.

[Surgical Treatment of Sacral Chordoma]. / Operacní lécba chordomu sakra.

PURPOSE OF THE STUDY The retrospective study of patients treated for sacral chordoma with respect of complications, clinical outcomes and longterm survival is presented. Three main hypotheses have been formulated. Hypothesis 1: survival of patients with respect to generalization of the disease, manifestation of local recurrence and metastases with a R0 resection margin achieved is longer than survival of patients with a R1 or R2 resection margin. Hypothesis 2: survival of patients with the tumor resected from low endplate of S2 distally is longer than in tumors with resection above this level. Hypothesis 3: resection of large tumors with tumor volume greater than 800 cm³ is associated with a significantly shorter survival than resection of tumors with tumor volume less than 800 cm³. MATERIAL AND METHODS A total of 12 patients (7 women, 5 men), with the mean age of 54.3 years, underwent surgical treatment at our department in 1998-2018. Sacral chordoma proximally achieved S1 level in three cases, S2 level in four cases and S3 level in five cases with volume less than 800 cm³ in eight and greater in four patients. In nine patients sacrectomy using isolated posterior approach was performed and in three patients antero-posterior approach was applied. The Kaplan-Meier survival curve was calculated to estimate the survival of patients. The patients were divided into groups and subsequently compared with respect of achieved radicality of surgical resection, i.e. R0 vs. R1 or R2 resection, secondly of the proximal margin of the tumor/resection, i.e. S1 or S2 vs. S3 distally, and thirdly of the volume of the tumor, i.e. less than 800 cm³ vs. more than 800 cm³. RESULTS At the time of evaluation, a total of seven patients were alive (58.3%), with the mean survival of 9.5 years. One patient died from complications associated with the treatment of obstructive ileus manifested 10 months after primary surgery. The remaining four patients died in relation to the generalization of the disease 14.8 years after primary surgery on average. All the patients, in whom R0 resection was achieved, at the average time of evaluation of 7.3 years (range 2.8-15.8 years) showed no signs of local recurrence or generalization of the disease, whereas in group with R1, R2 resection at the time of evaluation only two patients were still alive, both 16.8 years on average (range 15.2-18.4 years) after surgery with repeatedly treated recurrencies. Frequent postoperative complications were observed in a total of five patients (41.7%). DISCUSSION The study did not confirm any difference in patient's survival with respect of the proximal margin affection of sacrum or tumor size. The decisive factor for survival of patients with sacral chordoma is achieving the R0 resection. The size of the chordoma and proximal achievement increase the complexity of surgery, manifestation of early perioperative and subsequently postoperative complications. CONCLUSIONS In primary surgical treatment of sacral chordoma, we always try to achieve R0 resection. In the case of low-volume tumors from S3 distally, we resect the tumor using the isolated posterior approach. The anterior-posterior approach is preferred in the case of large tumors presenting in the S1/2 region. Key words: sacral chordoma, sacral cancer, wide resection, sacrectomy, vertical rectus abdominus myocutaneous (VRAM) flap.

[Neoadjuvant Use of Isolated Limb Perfusion in Large Myxoid Liposarcoma of the Thigh: a Case Report]. / Neoadjuvantní uzití izolované perfuze koncetiny u objemného myxoidního liposarkomu stehna: kazuistika.

Large unresectable STS presents a therapeutic challenge. Several options are being explored to avoid amputation without compromising the oncological outcome. Neoadjuvant chemotherapy delivers inconsistent and rather unsatisfactory results, preoperative radiotherapy compromises healing, hence it can impede adjuvant systemic treatment. We present a case report of neoadjuvant use of isolated limb perfusion with TNF-alfa and Alkeran (Melphalan) in a patient with initially unresectable large myxoid liposarcoma of the thigh. We achieved 55% reduction in size of the tumor that allowed for wide resection with a safe margin. Pathology confirmed 99% tumor necrosis. The patient has a full function of his extremity and is disease-free at one year follow-up. ILP should be considered as a treatment option which, in selected cases, can contribute to limb sparing surgery. Key words: sarcoma, soft tissue, regional perfusion, chemotherapy, surgery, orthopedic, limb salvage.

[Surgical Treatment of Cervical Spondylodiscitis]. / Operacní lécba krcní spondylodiscitidy.

PURPOSE OF THE STUDY The purpose of the retrospective study is to analyse a group of patients surgically treated for cervical spondylodiscitis. The first hypothesis states that the removal of infected intervertebral disc without its anterior column reconstruction in the acute phase of infection results in worse clinical and radiological evaluation of the patient. The second hypothesis defines that the use of titanium implant in anterior column reconstruction in the chronic phase of infection increases the risk of recurrent infection. MATERIAL AND METHODS The evaluated group of patients who underwent surgery includes a total of 21 patients (8 females, 13 males) with the mean age of 57.6 years. 12 patients in the acute phase of infection were treated by anterior debridement without disc space reconstruction, of whom four patients were completed by posterior instrumented fusion in the second stage. In 9 patients in the chronic phase of infection radical anterior debridement was completed by anterior titanium implant reconstruction, of whom in five patients posterior instrumented fusion was performed in the second stage. All patients were clinically evaluated by mJOA, VAS and Frankel score preoperatively, at 6 months and at 1 year postoperatively. The radiologic evaluation assessed the instrumentation failure, spinal fusion and kyphosis progression measured by sagittal Cobb angle. RESULTS The mJOA values improved from the mean preoperative value of 1.6 to 13.15 (6M) and 13.3 (1Y) postoperatively (p = 0.055). The VAS score increased from the mean value of 8.5 preoperatively to 2.15 (6M) and 1.35 (1Y) postoperatively (p < 0.001). No patient reported worse neurological finding postoperatively. The kyphosis progression measured by sagittal Cobb angle from the preoperative +6.7 decreased to +3.2 degrees at 1 year after surgery. The group of 12 patients treated in the acute phase of infection by anterior debridement without anterior column reconstruction showed worsening of kyphosis from +1.1 before surgery to +1.6 degrees at 1 year after surgery. The group of eight patients treated in the chronic phase by anterior debridement and reconstruction of the anterior column by implant changed from +15.9 before surgery to +6.1 degrees at 1 year after surgery. In two out of 12 patients with neurological deficit, the T2-weighted MRI finding of signal hyperintensity showed no improvement of the neurological deficit. DISCUSSION In the group of all operated patients, neither the worsening in the clinical evaluation using the mJOA or VAS score, nor kyphosis progression measured by Cobb angle in the sagittal plane, or failure of instrumentation in the anteroposterior procedure were reported postoperatively. In a total of nine patients operated on during the chronic phase of infection, in whom titanium implant was used to reconstruct the anterior column defect, no recurrent deep infection was observed. CONCLUSIONS In the acute phase we prefer anterior debridement with epidural abscess evacuation without anterior column reconstruction and posterior instrumented fusion in case of kyphosis progression in the second stage. In the chronic phase, radical anterior debridement with titanium implant reconstruction, eventually with posterior instrumented fusion is preferred. Key words: cervical spondylodiscitis, epidural abscess, anterior debridement, bacterial biofilm.

[Rotational Laxity of the Knee Joint - In Vivo MRI Study]. / Rotacní laxita kolenního kloubu ­ in vivo NMR studie.

PURPOSE OF THE STUDY The purpose of the study was to evaluate tibio-femoral rotation during a simulated squat and to investigate the relationship between the rotational position of the femur in full extension and the amount of external rotation of the femur on the tibia during flexion. MATERIAL AND METHODS Part 1: MRIs of volunteers Data on healthy knees of 10 volunteers were obtained using 2D MRI measurements. The foot and the ankle were fixed to prevent rotation and adduction/abduction movements. Sagittal MRIs of the knees have been performed in 4 positions of flexion. The amount of longitudinal rotation in each position of flexion was calculated. Part 2: Mathematical model experiment a) The model of the femur has been positioned in the 3D coordinate system in full extension and at 12.8° of internal rotation and then flexed to 90° without longitudinal rotation. The distance between the centre of the femoral head and the sagittal plane passing through the centre of the knee was then measured. b) Subsequently, the femur was flexed and rotation allowed to retain femoral head within the sagittal plane. The amount of femoral rotation was then calculated. RESULTS Part 1: In full extension the femur was on average in 12.8° of IR relative to the tibia. By 90° flexion femur rotated on average 12.2° externally. Part 2: a)From full extension to 90° flexion the femoral head moved 93.1 mm laterally from the sagittal plane. b)Between full extension and 90° flexion the femur rotated 12.8° externally, a degree which corresponds to the amount of initial internal rotation of the femur in full extension. DISCUSSION The most important finding of the presented in vivo study lies in the fact that in normal knees with tibia rotationally fixed flexion is always coupled with femoral external rotation in order to keep the femoral head in the acetabulum. This rotation is obligatory. CONCLUSIONS We have demonstrated that if the tibia is rotationally fixed, the knee flexion is possible only when accompanied by femoral external rotation to keep the femoral head in the acetabulum. A mathematical description of the experiment has been proposed, the results of which confirm the stated premise. This finding can be explained by initial internal rotation of the femur in full extension of the knee and is allowed by the shape of articulating bones and tension of soft tissues Key words: knee, terminal extension, knee rotation, knee movement, MRI, hip joint.

Autologous structural iliac bone grafts in reconstructions of short bone defects in the hand and foot after primary bone tumor resections: a single-institution retrospective study.

The use of structural autografts from the iliac crest for reconstruction of bony defects in the hand and foot was described by Wilson and Lance in 1965. However, very few series of this technique are published and long-term results are unknown. We present a single-institution series of 23 patients with a mean follow-up of 92 months. We also describe a novel modification of this technique using the anterior superior iliac spine for reconstruction of the adjacent joint. Failure rate was 13% at mean of 17.3 months. All patients had a firm grip in the hand and walked without support. Bony fusion was achieved in all cases regardless of the type of fixation used. The use of ASIS for joint reconstruction was successful, particularly in low-demand joints. We encountered 1 case of instability and progressive stiffness in weight-bearing joints. This is a reliable method of reconstructing bony defects in the hand or foot following tumor resections.

[Periprosthetic Infection of the Knee Megaprosthesis following a Resection of Malignant Tumours around the Knee]. / Periprotetické infekce megaprotéz po resekcích kostních nádoru oblasti kolene.

PURPOSE OF THE STUDY The study presents the monocentric retrospective study of a group of patients with malignant tumours around the knee, treated by a wide resection and a reconstruction with megaprosthesis due to infectious complications. Provided is a detailed analysis of each operative treatment due to the manifestation and process of periprostethic infection of the knee megaprosthesis and the use of external fixator during a two-stage revision. MATERIAL AND METHODS Between 01/1993 and 12/2013, a total of 67 cemented megaprostheses were assessed, with a detailed analysis of 12 patients with periprosthetic infection. The Kaplan-Meier method and MSTS for lower extremity clinical assessment were used and a range of motion was evaluated. RESULTS The endoprosthesis failed due to all kinds of complications (mechanical, biological, infection) in 27 (40.3%) patients. The estimated one-year survival rate from the surgery was 94%, the five-year survival rate was 72%, and the ten-year survival rate was 46%. Based on the statistical analysis of the implant survival due to infection, the one-year survival rate was 94%, the five-year survival rate was 75%, and the ten-year survival rate was 57%. Three patients were treated with radical surgical debridement. Five patients were treated with a two-stage revision with a cement spacer and external fixator, and three patients underwent nail fixation. Clinical values before and two years after the revision surgery for periprosthetic infection using MSTS were assessed. The mean of the difference of clinical values was 1.91 and the p value of paired t-test was 0.24, therefore there was no prove of the clinical result difference using MSTS before and after the revision surgery. DISCUSSION The acute radical debridement and lavage is preferred, if the surgery can be done up to three weeks after the first clinical signs of infection under the condition of good retention of the implant. In case of extensive infectious damage, when abscess, fistula and loosening of the implant are present and when the patient has a good oncological prognosis, we prefer a twostage revision with a cement spacer stabilized by an external fixator. In patients with mitigated infection or uncertain oncological prognosis we prefer a two-stage revision with the combination of a cement spacer and intramedullary nail fixation. CONCLUSIONS The study presents the results of operative treatment of periprosthetic infection of megaprosthesis and the modification of the two-stage replantation of infected MP with the use of external fixation for stabilisation of a non-articulated cement spacer allowing the patient to remain active during the time before the second stage. Key words: periprosthetic infection, megaprosthesis, bone tumour, external fixator, two-stage revision.