Thilo Khakzad

Dr. Thilo Khakzad


Research Focus & Metrics

Academic Career Length

6Years (2021-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

View All Publications
25 October 2022 in Life
Verified
Journal Article
Open access
PDF file
SWSilvan Wittenberg
Silvan Wittenberg
MPMelissa Paraskevaidis
Melissa Paraskevaidis
AJArmin Jarosch
Armin Jarosch
Anne FlörckenAnne Flörcken
Anne Flörcken
FBFranziska Brandes
Franziska Brandes
DRDaniel Rau
Daniel Rau
Soft tissue sarcomas (STSs) are a diverse group of rare malignant soft tissue tumors with a high disease burden. Treatment protocols are complex and, to this day, a precise recommendation for the surgical margin width is lacking. The present study aims to analyze the width of the surgical margins in STS resection specimens and analyze them for local and systemic disease-free survival as well as for most frequent histologic STS subtypes. A total of 169 consecutive patients diagnosed and treated in curative intent in our institution following a primary and localized STS of the extremities or trunk from January 2010 to December 2020 were included in this study regardless of age. Our data reveal that low-grade STSs are best controlled locally by a surgical margin ≥2 mm and in this way also preventing distant metastases effectively. Local recurrence-free survival and metastasis-free survival in high-grade STS were improved by intact muscle fascia or periosteum at the margin when compared only to soft tissue. However, the outcome was independent of the surgical margin width, suggesting a close but negative margin may be safe in high-grade STS subtypes with less invasive growth patterns when combined with adjunct radiochemotherapy.

17 December 2022 in Life
Verified
Journal Article
Open access
PDF file
TKThilo Khakzad
Thilo Khakzad
DKDaniel Karczewski
Daniel Karczewski
LTLeonard Thielscher
Leonard Thielscher
KRKonstantin Reiter
Konstantin Reiter
SWSilvan Wittenberg
Silvan Wittenberg
Sven MaerdianSven Maerdian
Sven Maerdian
Introduction: The risk of prosthetic joint infection (PJI) in mega-prosthesis for malignancy is increased compared with non-tumor cases. While several studies describe PJI in tumor-related arthroplasty, prospective studies comparing infection characteristics among different joints are limited. The present study analyzes mega-arthroplasty for hip, knee, and shoulder malignancy and compares the epidemiology, diagnosis, microbe spectrum, treatments, and outcomes between the different entities. Methods: The retrospective inclusion criteria were as follows: (1) mega-arthroplasty (2) in the hip, knee, or shoulder joint and a total femur arthroplasty (3) following a malignant bone tumor or metastasis (4) between 1996 and 2019. All included patients were prospectively followed and invited for a renewed hospital examination, and their PJI characteristics (if identified) were analyzed using both retrospective as well as newly gained prospective data. A PJI was defined according to the Infectious Disease Society of America (IDSA) and re-infection was defined according to the modified Delphi Consensus criteria. Results: In total, 83 cases of tumor mega-arthroplasty at a mean follow-up of 3.9 years could be included (32 knee, 30 hip, and 19 shoulder cases and 2 cases of total femur arthroplasty). In total, 14 PJIs were identified, with chondrosarcoma in 6 and osteosarcoma in 3 being the leading tumor entities. Knee arthroplasty demonstrated a significantly higher rate of PJI (p = 0.027) compared with hips (28.1% vs. 6.7%), while no significant difference could be found between the knee and shoulder (10.5%) (p = 0.134) or among shoulder and hip cases (p = 0.631). The average time of PJI following primary implantation was 141.4 months in knee patients, 64.6 in hip patients, and 8.2 months in shoulder patients. Age at the time of the primary PJI, as well as the time of the first PJI, did not show significant differences among the groups. Thirteen of the fourteen patients with PJI had a primary bone tumor. Statistical analysis showed a significant difference in the disadvantage of primary bone tumors (p = 0.11). While the overall cancer-related mortality in the knee PJI group (10%) was low, it was 50% in the hip and 100% in the shoulder group. Conclusion: The risk of PJI in knee tumor arthroplasty is significantly increased compared with hips, while cancer-related mortality is significantly higher in hip PJI cases. At the same time, mega-prostheses appear to be associated with a higher risk of infection due to a primary bone tumor compared with metastases. The study confirms existing knowledge concerning PJI in tumor arthroplasty, while, being one of the few studies to compare three different joints concerning PJI characteristics.

22 December 2021 in Journal of Clinical Medicine
Verified
Journal Article
Open access
PDF file
SHSebastian Hardt
Sebastian Hardt
VLVincent Justus Leopold
Vincent Justus Leopold
TKThilo Khakzad
Thilo Khakzad
Matthias PumbergerMatthias Pumberger
Matthias Pumberger
CPCarsten Perka
Carsten Perka
CHChristian Hipfl
Christian Hipfl
Background: This study sought to compare the results of two-stage revision total hip arthroplasty (THA) for periprosthetic infection (PJI) in patients with and without the use of an extended trochanteric osteotomy (ETO) for removal of a well-fixed femoral stem or cement. Methods: Thirty-two patients who had undergone an ETO as part of a two-stage revision without spacer placement were matched 1:2 with a cohort of sixty-four patients of the same sex and age who had stem removal without any osteotomy. Clinical outcomes including interim revision, reinfection and aseptic failure rates were evaluated. Modified Harris hip scores (mHHS) were calculated. Minimum follow-up was two years. Results: Patients undergoing ETO had a significantly lower rate of interim re-debridement compared to non-ETO patients (0% vs. 14.1%, p = 0.026). Reinfection following reimplantation was similar in both groups (12.5% in ETO patients vs. 9.4% in non-ETO patients, p = 0.365). Revision for aseptic reason was necessary in 12.5% in the ETO group and 14.1% in the non-ETO group (p = 0.833). Periprosthetic femoral fractures were seen in three patients (3.1%), of which all occurred in non-ETO patients. Dislocation was the most common complication, which was equally distributed in both groups (12.5%). The mean mHHS was 37.7 in the ETO group and 37.3 in the non-ETO group, and these scores improved significantly in both groups following reimplantation (p < 0.01). Conclusion: ETO without the use of spacer is a safe and effective method to manage patients with well-fixed femoral stems and for thorough cement removal in two-stage revision THA for PJI. While it might reduce the rate of repeated debridement in the interim period, the use of ETO appears to lead to similar reinfection rates following reimplantation.

22 December 2025 in European Spine Journal
Verified
Journal Article
Open access
PDF file
TFTom Niklas Folkerts
Tom Niklas Folkerts
LSLukas Schonnagel
Lukas Schonnagel
BHBernhard Ulrich Hoehl
Bernhard Ulrich Hoehl
LBLuis Vincent Bürck
Luis Vincent Bürck
IPIzabella Preininger
Izabella Preininger
FSFriederike Schömig
Friederike Schömig
Purpose: Segmental instability guides surgical decision-making in isthmic lumbar spondylolisthesis (ILS). Despite concerns regarding radiation exposure, reproducibility and applicability in patients with pain or limited mobility, flexion–extension (FE) radiographs remain the standard for instability assessment. Combining upright radiographs with supine magnetic resonance imaging (MRI), both routinely obtained in clinical practice, may offer a comparable, lower-radiation alternative. This study aimed to compare segmental motion at L5/S1 between FE and upright–supine (US) imaging and to evaluate their ability to detect radiographic instability. Methods: In this retrospective cross-sectional study, consecutive patients surgically treated for isolated L5/S1 ILS were screened for eligibility. Segmental motion was assessed using FE radiographs and US imaging, including measurements of dynamic sagittal translation and the proportion of patients identified with radiographic signs of instability. Preoperative pain intensity was assessed using the Numeric Rating Scale (NRS). Results: Of 126 screened patients, 78 met inclusion criteria (59% female; median age 48.5 years; median BMI 26.4 kg/m²). Dynamic sagittal translation was significantly greater on US than on FE ( p < 0.001). US imaging identified more cases of radiographic instability ( p < 0.001). Only US-measured translation was associated with preoperative low back pain intensity ( p = 0.025) and was inversely associated with intervertebral disc degeneration ( p = 0.014). Conclusions: US imaging detected a higher proportion of radiographically unstable ILS cases than FE radiographs. Furthermore, only US-derived translation was associated with pain intensity, suggesting greater clinical relevance. Combining upright radiographs with supine MRI may offer a practical, low-radiation alternative for preoperative instability assessment.

5 September 2025 in Journal of Clinical Medicine
Verified
Journal Article
Open access
PDF file
TKThilo Khakzad
Thilo Khakzad
MPMichael Putzier
Michael Putzier
LTLeonard Thielscher
Leonard Thielscher
NTNima Taheri
Nima Taheri
SWSilvan Wittenberg
Silvan Wittenberg
Sven MaerdianSven Maerdian
Sven Maerdian
Background/Objectives: Resection arthroplasty is well established in treating bone defects following tumor resection, with the distal femur and proximal tibia being its most common localizations. The aim of this study was to analyze the functional outcomes and quality of life following endoprosthetic reconstruction for malignant bone tumors of the knee joint. Methods: We retrospectively included all patients treated with an endoprosthetic reconstruction following resection of a malignant bone tumor of the knee at our institution. Functional outcomes (KOOS, OKS, MSTS, and KSS) and health-related quality of life scores [QoL] (SF-36, Karnofsky Index) were evaluated. Chi-square and Fisher’s exact test was used for categorical variables, T-test and Whitney U-Mann tests for continuous variables. Survival was calculated using the Kaplan–Meier curves. Results: 32 patients were included. A total of 12 patients had died at the time of follow-up. Among the remaining 20 patients (m:w 17:3), mean follow-up was 8.1 years (range, 8.12 ± 6.8). Mean age at the time of tumor diagnosis was 50 ± 23.3 (10–83) years. According to age, patients were divided into two groups (group C1: 29 years). Group C1 showed significantly better results regarding functional outcome (p < 0.05). The anatomic location of the replacement and a revision surgery did not influence the functional outcome (p > 0.05). QoL showed no significant differences in subgroup analysis (p > 0.05). Primary bone tumors had a significantly better survival (primary tumor: 216.90 months [168.42–265.83]; secondary tumor: 37.03 months [11.71–62.35] p = 0.01). Furthermore, pathologic fractures were associated with significantly worse survival (pathologic fracture: 50.24 months [0.00–102.43]; pathologic fracture 190.63 moths [139.28–241.45]; p = 0.007). Conclusions: Knee resection arthroplasty can offer meaningful long-term functional outcomes and acceptable quality of life in selected patients with musculoskeletal tumors. While the rarity and heterogeneity of such cases remain a challenge, our findings contribute to the growing evidence supporting this complex but limb-sparing surgical option.

25 September 2025 in Bone & Joint Open
Verified
Journal Article
Open access
PDF file
TKThilo Khakzad
Thilo Khakzad
SMSebastian Meller
Sebastian Meller
SHSebastian Hardt
Sebastian Hardt
VLVincent J. Leopold
Vincent J. Leopold
LMLukas Mödl
Lukas Mödl
TWTobias Winkler
Tobias Winkler
Aims: The classic, widely accepted approach for one-stage hip revision arthroplasty in patients with periprosthetic joint infection (PJI) is the cemented exchange. This approach provides stable implant anchoring despite bone defects after removal of infected components, and facilitates local antibiotic delivery. This study aims to investigate the efficacy of cementless one-stage hip revision arthroplasty using a gentamicin-eluting bone graft substitute (GBGS) to address both bone defect filling and antibiotic elution.Methods: We conducted a prospective analysis of 20 patients with confirmed PJI undergoing cementless one-stage hip revision arthroplasty using GBGS. The GBGS was used to fill femoral and acetabular defects during implantation. Clinical outcomes, radiographs, adverse events, and patient-reported outcome measures (PROMs) including Harris Hip Score (HHS) and EuroQol five-dimension five-level questionnaire (EQ-5D-5L) were assessed. Patients received 12 weeks of systemic antibiotics and were followed up for at least 24 months.Results: The mean age of the cohort was 66.3 years (SD 8.4; 46 to 80), with ten female and ten male patients. On average, 13.2 ml (SD 3.9; 5 to 17) of GBGS was applied to bone defects. No reinfections occurred during the follow-up period of 3.3 years (SD 0.92; 2.1 to 4.8). We observed 15 serious adverse events (SAEs), none of which were associated with the product. All cases showed good bony consolidation and prosthesis integration at 12 months. Significant improvements were seen in HHS (preoperative mean: 47.7; final visit mean: 80.1; p < 0.001) and EQ-5D-5L score (preoperative mean: 0.43; 12-month mean: 0.88; p < 0.001).Conclusion: This prospective pilot study is the first to demonstrate the safety and feasibility of single-stage cementless hip exchange arthroplasty using GBGS in managing PJI and associated bone defects. The technique resulted in significant improvements in functional outcomes and quality of life, with a good safety profile. Further studies with larger cohorts are warranted to validate these findings.Cite this article: Bone Jt Open 2025;6(9):1146–1155.