3D-printed glenoid implant reconstruction, after partial scapulectomy for malignant tumors: a case series.

PURPOSE: Glenoid tumors are extremely rare, and reconstruction remains very challenging. The aim of this study is to present the clinical and functional outcomes, of a new glenoid reconstruction method using 3-dimensional-printed implant. METHODS: Four patients with primary glenoid tumors underwent reconstruction using 3-dimensional-printed glenoid implant linked with reverse shoulder arthroplasty. We retrospectively reviewed the clinical and functional outcome, using MSTS and DASH score, as well as complications' rate. RESULTS: Wide excision was achieved in all patients. No local recurrence or distant metastasis was diagnosed at the follow-up period. The mean MSTS score was 80.5%, and DASH score was 15.2%. According to Hendersons' classification, there were no postoperative complications. CONCLUSION: The use of 3-dimensional-printed implants, can be a very reliable solution with satisfying clinical and functional outcomes for reconstruction, in patients with musculoskeletal malignancies of the glenoid. Level of evidence IV Treatment Study.

Milder impact of the COVID-19 pandemic on the practice of orthopaedic surgery in Greece and Cyprus than other European countries.

PURPOSE: The aim of this study was to highlight the impact of the COVID-19 pandemic on the practice of orthopaedics in Greece and Cyprus. METHODS: The survey used the online questionnaire from AGA (Gesellschaft für Arthroskopie und Gelenkchirurgie; Society for Arthroscopy and Joint Surgery) to facilitate the comparison between different European countries. The questionnaire was distributed online to members of the HAOST (Hellenic Association of Orthopaedic Surgery and Trauma), the ΟΤΑΜΑΤ (Orthopaedic and Trauma Association of Macedonia and Thrace) and the CAOST (Cypriot Association of Orthopaedic Surgery and Trauma). The questionnaire consisted of 29 questions, which included demographic data, questions on the impact of the pandemic on the practice of orthopaedic surgery and questions on the impact on the personal and family life of orthopaedic surgeons. RESULTS: The questionnaire was sent to 1350 orthopaedic surgeons in Greece and Cyprus, 303 of whom responded (response rate 22.44%). 11.2% of the participants reported cancellation of overall orthopaedic procedures. According to 35.6-49.8% of the participants, arthroscopic procedures were continued. As regards elective primary arthroplasties, 35.3% of the participants reported that these continued to be performed at their hospitals. Post-operative follow-ups as well as physiotherapy were affected by the pandemic, and changes were also observed in the habits of orthopaedic surgeons in their personal and family lives. CONCLUSION: The orthopaedic service in Greece and Cyprus decreased during the first wave of the COVID-19 pandemic. Arthroscopic procedures and total joint replacements decreased significantly, but not to the same extent as in other countries. Health systems were not fully prepared for the first wave of the pandemic and the various countries took social measures at different times and to different extents. Thus, studying the impact of the pandemic on the practice of orthopaedic surgery in different countries can help health systems to better prepare for future pandemics; public health can then be shielded and hospitals can continue to provide high-quality orthopaedic care. LEVEL OF EVIDENCE: Level V.

Marika Daniilidou, MD. The First Female Orthopaedic Surgeon in Greece.

Dr Marika Daniilidou was born in 1902 in Asia Minor. Her family was forced to immigrate to Greece, in 1922. Despite the horrendous difficulties of the era, she pursued undergraduate and postgraduate studies in the University of Berlin, Germany, and she specialized in orthopaedic surgery. In 1937, she became the first female certified orthopaedic surgeon in Greece. In 1947, she was the only female orthopaedic surgeon among the 22 founders of the Hellenic Association of Orthopaedic Surgery and Traumatology (HAOST). She became a true role model for the next generations of Greek women surgeons.

The Evolution of Orthopaedics in Greece: From Ancient Heritage to Modern Times.

Greece, one of the oldest civilizations of the world, fundamentally contributed to the establishment and evolution of medicine and surgery. Undoubtedly, the foundations of the orthopaedic science are dated back to antiquity. The journey of the orthopaedic art was inaugurated with the poems of Homer and incarcerated through the practices of Hippocrates and Galen. Their deep knowledge of the musculoskeletal conditions and their treatment was generously bequeathed to humanity. This heritage acted as the catalyst for the establishment of orthopaedics in the modern Greek era. In this article, we tried to illustrate the evolution of the orthopaedic art in Greece from antiquity to modern times, reviewing the available evidence from scientific articles, books, historical manuscripts, old newspapers, and biographies. We summarize the most important events, and we identify the pioneers that shaped this new surgical branch, creating the modern Greek orthopaedic discipline.

Cross-cultural adaptation and validation of the Musculoskeletal Tumor Society (MSTS) scoring system and Toronto Extremity Salvage Score (TESS) for musculoskeletal sarcoma patients in Greece.

PURPOSE: To perform translation, cross-cultural adaptation, and validation of the Toronto Extremity Salvage Score (TESS) and Musculoskeletal Tumor Society (MSTS) scoring system in Greek patients with lower extremity sarcoma. METHODS: The Greek version of the MSTS for the lower extremity and TESS questionnaires was developed using previously reported methods. Included were 100 patients with musculoskeletal sarcoma who underwent limb salvage surgery. The test-retest reliability [interclass correlation coefficient (ICC) between 2 different time points], internal consistency (Cronbach's alpha), construct validity (Kaiser's criteria, Eigenvalue > 1 rule), and external validity (Short form-36, Spearman's Rho) were assessed. RESULTS: The test-retest reliability (ICC was 0.99 for MSTS-LE and 1 for TESS) and internal consistency were high (Cronbach's alpha was 0.763 for MSTS-LE and 0.924 for TESS) for both questionnaires. Based on the Scree plot, the number of factors retained was 1 for MSTS-LE and 2 for TESS. The TESS showed a strong correlation with SF-36 (Spearman's rho = 0.714, p < 0.001), but the correlation between MSTS for lower extremity and SF-36 was weak (Spearman's Rho = 0.313, p = 0.002). CONCLUSIONS: The Greek version of both the MSTS for lower extremity and TESS questionnaire showed sufficient reliability, internal consistency and good performance using the loading factor analysis when used postoperatively in Greek patients who underwent surgical resection of lower extremity sarcoma. However, only the TESS showed strong correlation with the SF-36, indicating that MSTS for lower extremity was not as powerful for the evaluation of the global health status of these patients.

Hallmarks in the History and Development of Total Hip Arthroplasty.

Total hip replacement remains one of the most successful and popular operative techniques in orthopedic surgery. Over several decades, several patients have been benefited by this mechanical and surgical achievement. It is an innovation that stands among the most significant surgical and technological achievements of the 20th century. The purpose of this review was to summarize the main landmarks on the evolution of hip surgery and the resulting modern total hip arthroplasty technique.

Ball-joint versus single monolateral external fixators for definitive treatment of tibial shaft fractures.

PURPOSE: To compare modular monolateral external fixators with single monolateral external fixators for the treatment of open and complex tibial shaft fractures, to determine the optimal construct for fracture union. MATERIALS AND METHODS: A total of 223 tibial shaft fractures in 212 patients were treated with a monolateral external fixator from 2005 to 2011; 112 fractures were treated with a modular external fixator with ball-joints (group A), and 111 fractures were treated with a single external fixator without ball-joints (group B). The mean follow-up was 2.9 years. We retrospectively evaluated the operative time for fracture reduction with the external fixator, pain and range of motion of the knee and ankle joints, time to union, rate of malunion, reoperations and revisions of the external fixators, and complications. RESULTS: The time for fracture reduction was statistically higher in group B; the rate of union was statistically higher in group B; the rate of nonunion was statistically higher in group A; the mean time to union was statistically higher in group A; the rate of reoperations was statistically higher in group A; and the rate of revision of the external fixator was statistically higher in group A. Pain, range of motion of the knee and ankle joints, rates of delayed union, malunion and complications were similar. CONCLUSION: Although modular external fixators are associated with faster intraoperative fracture reduction with the external fixator, single external fixators are associated with significantly better rates of union and reoperations; the rates of delayed union, malunion and complications are similar.

A 3D-printed load sharing implant achieved union of a 9-cm femoral segmental bone defect within three months using a hybrid Masquelet induction membrane technique. A case-report.

Case: A 30-year-old male was admitted in our hospital having an open left distal femoral fracture with 9-cm segmental bone defect and a closed proximal left tibial fracture. He was treated successfully using a Hybrid (Titanium Cage and Bone Graft) Masquelet Induction Membrane Technique (MIMT). His femoral fracture united 3-months post - operatively. The left tibia was treated initially with two locking plates. Following infection, a 3-cm tibial bone gap was treated with external fixation and conventional MIMT. The tibial fracture united 12-months post- operatively. Conclusion: The Hybrid MIMT achieved a successful healing outcome in this challenging case.

Complications Following Intraosseous Injections of Calcium Phosphate Bone Cement in Subchondroplasty.

An alternative approach to the major problem of osteoarthritis that has begun to pique the interest of researchers focuses on the pathology of the subchondral bone, its constant cross-talk with the articular cartilage, and its interaction with the joint. The presence of bone marrow lesions, detectable on MRI scans, has proven to be a cause of pain as well as a predictor of the progression of degenerative changes. Subchondroplasty is a relatively new surgical procedure for the treatment of these lesions, in which injectable calcium phosphate bone cement is infused into the affected area percutaneously, under fluoroscopic guidance. In its use as a synthetic scaffold, calcium phosphate bone cement exhibits considerable osteoconductivity, bioabsorbability, and low toxicity, thus showing great potential for restoring subchondral biomechanical properties through structural remodeling. Although published results appear quite promising, there are certain complications that the surgeon should be aware of. We reviewed the published data regarding complications of the procedure, highlighting possible causes according to these data, and suggesting safety measures. Avascular necrosis of the talus is the most reported concern. Postsurgical pain, infection, and continuous wound drainage due to bone substitute material extravasation to the joint or soft tissue are also mentioned, necessitating further standardization of the procedure. There are no reports of permanent postoperative disability or fatal outcomes.

Bone mineral density, vitamin D and osseous metabolism indices in neurofibromatosis type 1: A systematic review and meta-analysis.

BACKGROUND: Neurofibromatosis type 1 (NF1) is a genetic autosomal neurocutaneous syndrome correlated with skeletal dysplasia and defects in the osseous microarchitecture. The physiological mechanism for the development of NF1-related bone abnormal turnover is still unclear. OBJECTIVES: A meta-analysis was performed to investigate the effects of NF1 on bone mineral density (BMD) and osseous metabolic indices in order to provide clinical evidence for the pathogenesis of the associated skeletal deformities. METHODS: A systematic literature review search was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines in the PubMed/Medline and Web of Science databases from the date of inception of each database through to 10 September 2023. Specific inclusion and exclusion criteria were applied for the identification of studies examining the effects of NF1 on bone strength and metabolism. The Newcastle-Ottawa and Jadad scales were applied to assess the quality of the included studies. RevMan 5.3 software was used for the analysis of the data, and MedCalc was applied to examine publication bias. RESULTS: Overall, 13 studies met the inclusion criteria comprised of 5 cross-sectional, 6 case-control and 2 retrospective studies. 703 patients and 973 healthy subjects formed the NF1 and control group, respectively. The results of the meta-analysis displayed that lumbar (SMD = -3.85, 95%CI = -7.53 to -0.18, Z = 2.05, p = 0.04) and femoral (SMD = -4.78, 95%CI = -8.86 to -0.69, Z = 2.29, p = 0.02) BMD was reduced in the NF1 group. Both in children and adults the serum levels of 25 hydroxyvitamin D3 were also decreased in NF1 group, but without any statistical significance (SMD = -0.62, 95%CI = -1.34 to -0.11, Z = 1.66, p = 0.10). Serum Parathyroid hormone (PTH) (SMD = 0.73, 95%CI = 0.31 to 1.15, Z = 3.43, p = 0.0006) and C-telopeptide of type 1 collagen (CTX) (SMD = 0.82, 95%CI = 0.33 to 1.30, Z = 3.29, p = 0.001) were elevated in NF1 patients, while serum calcium (SMD = -0.10, 95%CI = -0.74 to 0.53, Z = 0.32, p = 0.75) phosphorous (SMD = 0.33, 95%CI = -0.38 to 1.05, Z = 0.92, p = 0.36), alkaline phosphatase (ALP) (SMD = -0.36, 95%CI = -0.77 to 0.05, Z = 1.71, p = 0.09), osteocalcin (SMD = 1.81, 95%CI = -0.37 to -3.98, Z = 1.63, p = 0.10) and bone formation markers (SMD = 0.28, 95%CI = -0.37 to -0.94, Z = 0.85, p = 0.39) were not. CONCLUSION: NF1 is associated with decreased BMD at the lumbar spine and femur. Taking into account that the serum levels of PTH, CTX were increased whereas the concentrations of vitamin D, calcium, phosphorous, ALP, osteocalcin and bone formation markers were not altered significantly in the NF1 patients compared with the healthy subjects, a vitamin D independent dysregulated bone cellular activity could be considered. STUDY REGISTRATION: Registered on PROSPERO (CRD42023424751).

Current Progress and Future Perspectives in Contact and Releasing-Type Antimicrobial Coatings of Orthopaedic Implants: A Systematic Review Analysis Emanated from In Vitro and In Vivo Models.

Background: Despite the expanding use of orthopedic devices and the application of strict pre- and postoperative protocols, the elimination of postoperative implant-related infections remains a challenge. Objectives: To identify and assess the in vitro and in vivo properties of antimicrobial-, silver- and iodine-based implants, as well as to present novel approaches to surface modifications of orthopedic implants. Methods: A systematic computer-based review on the development of these implants, on PubMed and Web of Science databases, was carried out according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Results: Overall, 31 in vitro and 40 in vivo entries were evaluated. Regarding the in vitro studies, antimicrobial-based coatings were assessed in 12 entries, silver-based coatings in 10, iodine-based in 1, and novel-applied coating technologies in 8 entries. Regarding the in vivo studies, antimicrobial coatings were evaluated in 23 entries, silver-coated implants in 12, and iodine-coated in 1 entry, respectively. The application of novel coatings was studied in the rest of the cases (4). Antimicrobial efficacy was examined using different bacterial strains, and osseointegration ability and biocompatibility were examined in eukaryotic cells and different animal models, including rats, rabbits, and sheep. Conclusions: Assessment of both in vivo and in vitro studies revealed a wide antimicrobial spectrum of the coated implants, related to reduced bacterial growth, inhibition of biofilm formation, and unaffected or enhanced osseointegration, emphasizing the importance of the application of surface modification techniques as an alternative for the treatment of orthopedic implant infections in the clinical settings.

Unraveling the Link of Altered TGFß Signaling with Scoliotic Vertebral Malformations in Osteogenesis Imperfecta: A Comprehensive Review.

Osteogenesis Imperfecta (OI) is a genetic disorder caused by mutations in genes responsible for collagen synthesis or polypeptides involved in the formation of collagen fibers. Its predominant skeletal complication is scoliosis, impacting 25 to 80% of OI patients. Vertebral deformities of the scoliotic curves in OI include a variety of malformations such as codfish, wedged-shaped vertebrae or platyspondyly, craniocervical junction abnormalities, and lumbosacral spondylolysis and spondylolisthesis. Although the precise pathophysiology of these spinal deformities remains unclear, anomalies in bone metabolism have been implicated in the progression of scoliotic curves. Bone Mineral Density (BMD) measurements have demonstrated a significant reduction in the Z-score, indicating osteoporosis and a correlation with the advancement of scoliosis. Factors such as increased mechanical strains, joint hypermobility, lower leg length discrepancy, pelvic obliquity, spinal ligament hypermobility, or vertebrae microfractures may also contribute to the severity of scoliosis. Histological vertebral analysis has confirmed that changes in trabecular microarchitecture, associated with inadequate bone turnover, indicate generalized bone metabolic defects in OI. At the molecular level, the upregulation of Transforming Growth factor-ß (TGFß) signaling in OI can lead to disturbed bone turnover and changes in muscle mass and strength. Understanding the relationship between spinal clinical features and molecular pathways could unveil TGFß -related molecular targets, paving the way for novel therapeutic approaches in OI.

Point-of-Care Orthopedic Oncology Device Development.

BACKGROUND: The triad of 3D design, 3D printing, and xReality technologies is explored and exploited to collaboratively realize patient-specific products in a timely manner with an emphasis on designs with meta-(bio)materials. METHODS: A case study on pelvic reconstruction after oncological resection (osteosarcoma) was selected and conducted to evaluate the applicability and performance of an inter-epistemic workflow and the feasibility and potential of 3D technologies for modeling, optimizing, and materializing individualized orthopedic devices at the point of care (PoC). RESULTS: Image-based diagnosis and treatment at the PoC can be readily deployed to develop orthopedic devices for pre-operative planning, training, intra-operative navigation, and bone substitution. CONCLUSIONS: Inter-epistemic symbiosis between orthopedic surgeons and (bio)mechanical engineers at the PoC, fostered by appropriate quality management systems and end-to-end workflows under suitable scientifically amalgamated synergies, could maximize the potential benefits. However, increased awareness is recommended to explore and exploit the full potential of 3D technologies at the PoC to deliver medical devices with greater customization, innovation in design, cost-effectiveness, and high quality.

Subchondral Bone Cyst Development in Osteoarthritis: From Pathophysiology to Bone Microarchitecture Changes and Clinical Implementations.

Osteoarthritis is a degenerative joint disease affecting middle-aged and elderly patients. It mainly involves weight-bearing joints such as the hip, knee and spine as well as the basilar joint of the thumb, causing dysfunction and painful symptoms. Often, joint arthritis is accompanied by cartilage defects, joint space narrowing, osteophytes, bone sclerosis and subchondral bone cysts (SBC). The aim of the present study was to explore the pathophysiology responsible for the development of SBCs as well as the association between SBCs and disease progress, the level of clinical symptoms and their impact on postoperative outcomes and risk of possible complications following joint replacements if left untreated. A literature review on PubMed articles was conducted to retrieve and evaluate all available evidence related to the main objective mentioned above. A few theories have been put forth to explain the formation process of SBCs. These involve MMPs secretion, angiogenesis, and enhanced bone turnover as a biological response to abnormal mechanical loads causing repeated injuries on cartilage and subchondral tissue during the development of arthritis. However, the application of novel therapeutics, celecoxib-coated microspheres, local administration of IGF-1 and activated chondrocytes following surgical debridement of SBCs hinders the expansion of SBCs and prevents the progression of osteoarthritis.

Neuromuscular activity of the lower-extremities during running, landing and changing-of-direction movements in individuals with anterior cruciate ligament reconstruction: a review of electromyographic studies.

PURPOSE: Running, jumping/landing and cutting/change of direction (CoD) are critical components of return to sport (RTS) following anterior cruciate ligament reconstruction (ACLR), however the electromyographic (EMG) activity patterns of the operated leg during the execution of these tasks are not clear. METHODS: A systematic review was conducted to retrieve EMG studies during running, jumping/landing and cutting/(CoD) in ACLR patients. MEDLINE, PubMed, SPORTDiscus and Web of Science databases were searched from 2000 to May, 2022 using a combination of keywords and their variations: "anterior cruciate ligament reconstruction" OR "ACLR", "electromyography" OR "EMG", "running", "jumping" OR "landing", "cutting" OR "change-of-direction" OR "CoD". The search identified studies comparing EMG data during running, landing and cutting/(CoD) between the involved limb and contralateral or control limbs. Risk of bias was assessed and quantitative analyses using effect sizes were performed. RESULTS: Thirty two studies met the inclusion criteria. Seventy five percent (24/32) of the studies reported altered EMG activity pattern of the ACLR leg during running, jumping/landing and cutting/(CoD) when compared with either the healthy control leg or the contra-lateral leg. Twelve studies showed decreased, delayed or earlier onset and delayed peak in quadriceps EMG activity with small to large effect sizes and 9 studies showed increased, delayed or earlier onset and delayed peak in hamstrings EMG activity with small to large effect sizes. Four studies showed a "hamstrings-dominant" strategy i.e. decreased quadriceps coupled with increased hamstrings EMG activity in both running and jumping/landing irrespective of graft type. One study reported that on the grounds of decreased quadriceps activity, lower hamstrings EMG activity was predictive of ipsilateral re-injury in ACLR patients. CONCLUSION: This systematic review of Level III evidence showed that the ACLR leg displays decreased quadriceps or increased hamstrings EMG activity or both despite RTS. Simultaneous decreased quadriceps and increased hamstrings EMG activity was shown for both running and jumping/landing. From a clinical perspective this "hamstrings dominant" strategy can serve as a protective mechanism against graft re-injury. LEVEL OF EVIDENCE: III.

Impact of Preoperative Quality of Life and Related Factors on the Development of Surgical Site Infections Following Primary Total Joint Arthroplasty: A Prospective Case-Control Study with a Five-Year Follow-Up.

Introduction: As surgical site infections (SSIs) after joint arthroplasty contribute to increased morbidity and mortality, they require further surgical intervention, prolonged hospitalisation, and antimicrobial treatment. The aim of our study is to examine the association between preoperative quality of life (QoL) and other predictive factors on the development of SSIs after primary arthroplasty. Methods: This is a prospective study that enrolled 56 patients with hip and knee primary osteoarthritis who underwent joint replacement. Data were collected from January to March 2017, including patient demographic characteristics, comorbidities, laboratory results, and perioperative clinical data. The patients' QoL was evaluated preoperatively by applying the knee injury and osteoarthritis outcome score (KOOS) and the hip disability and osteoarthritis outcome score (HOOS) for total knee replacement (TKR) and total hip replacement (THR), respectively. A 5-year follow-up was conducted to assess the clinical status of the patients. Results: 66.1% of patients underwent TKR, with 4.9 ± 1.2 days of hospitalisation, 16% of them required autologous blood transfusion, while 33.9% of patients were treated with THR, with 5.7 ± 1 days hospitalisation and 36.8 of them required this type of transfusion. 16 patients were diagnosed with SSIs, with the older of them (>65 years old) presenting lower probability (odds ratio: 0.13, 95% CI: 0.03-0.62) requiring treatment with additional antibiotics, while revision surgery was performed in 3 of these cases, following periprosthetic joint infection (PJI). Overall preoperative QoL was not statistically associated with SSIs, but low QoL scores were associated with higher rates of SSIs and increased levels of postoperative pain (p = 0.009 < 0.05). Conclusions: The duration of each operation (>90 min), the length of hospitalisation (>4 days), and the presence of comorbidities including hypothyroidism and recurrent urinary tract infections were associated with a high risk for SSIs following arthroplasties. On the contrary, this study revealed no association between other comorbidities, including heart coronary disease, hypertension, and diabetes mellitus, with close monitoring of plasma glucose and SSIs. Moreover, the younger the patients, the more likely they were to require treatment with antibiotics. Overall, high QoL index scores were mainly accompanied by low rates of postoperative SSIs and pain.

Knee Arthrodesis with a Modular Silver-Coated Endoprosthesis for Infected Total Knee Arthroplasty with Extensive Bone Loss: A Retrospective Case-Series Study.

INTRODUCTION: Knee arthrodesis is a limb salvage intervention for persistent periprosthetic joint infection (PJI) when revision total knee arthroplasty fails. Conventional arthrodesis techniques are associated with the increased rate of complications, especially in patients with extensive bone loss and extensor tendon deficiency. METHODS: Eight patients with a modular silver-coated arthrodesis implant after failed exchange arthroplasty for infection, were retrospectively reviewed. All patients had significant bone loss, while 5 displayed extensor tendon deficiency. Survivorship, complications, leg length discrepancy, median Visual Analogue Scale (VAS) and Oxford Knee score (OKS) were evaluated. RESULTS: The median follow up was 32 months (range 24-59 months). The survivorship rate of the prosthesis was 86% during the minimum time of follow up of 24 months. In one patient recurrence of the infection was observed and above-knee amputation was performed. The median postoperative leg length discrepancy was 2.07 ± 0.67 cm. Patients were able to ambulate with mild or no pain. The median VAS and OKS was 2.14 ± 0.9 and 34.7 ± 9.3, respectively. CONCLUSIONS: The results of our study demonstrated that knee arthrodesis with a silver coated arthrodesis implant, performed for persistent PJI in patients with significant bone loss and extensor tendon deficit, provided a stable construct, allowed eradication of infection and was associated with good functional outcome.

Computer-assisted navigation in knee surgery.

Although computer-assisted navigation has been used in clinical practice for more than 15 years, it has only recently started to gain acceptance in a variety of orthopedic procedures. Different types of computer-assisted navigation are available, which allow the surgeon to obtain real-time feedback and offer him the potential to decrease intraoperative errors. However, its increased cost and lacking evidence of long-term superiority have made many surgeons skeptical about its clinical usefulness. The scope of this article is to review the clinical applications of computer-assisted navigation in orthopedic surgery of the knee joint.