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Orthopaedic Proceedings
Vol. 105-B, Issue SUPP_2 | Pages 26 - 26
10 Feb 2023
Chavan A Hoellwarth J Tetsworth K Lu W Oomatia A Alam S Vrazas E Al Muderis M
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Traditional socket prosthesis (TSP) rehabilitation for amputees is associated with substantial dissatisfaction due to poor mobility and pain from soft tissue squeezing. Osseointegration (OI), eliminates skin compression and prosthesis fit issues, providing superior mobility and quality of life (QOL) for most amputees. The potential for OI to benefit patients with exceptionally poor mobility is understudied. To address this knowledge gap, this project investigated the mobility and QOL changes.

A retrospective review was performed to identify transfemoral amputees who presented with wheelchair-bound mobility (K0) and had at least five years of post-osseointegration follow-up. Outcome measures included changes in mobility (K-level, daily prosthesis wear hours, Timed Up and Go (TUG), 6 minute walk test (6MWT)) and QOL (Questionnaire for persons with a Transfemoral Amputation (QTFA); Short Form Health Survey 36 (SF36). Adverse events recorded included debridement for infection, implant revision surgery, fractures, and implant failures.

9 patients with mean age 48.2±7.7 (range 34-59) years were included. The proportion of patients achieving K-level >2 improved from 0/9=0% to [9/9=100%], p<0.001. The 6MWT improved from 0±0 to 320.65±57 meters (p<0.001). The TUG improved from incapable to 10.68±2.7 seconds (p<0.001). Statistically significant QOL metrics included QTFA global score (33.33±31 vs 68.52±21, p=0.039), SF36 physical component score (30.03±6.3 vs 42.34±12, p=0.023) and the SF36 mental component score (47.89±8.8 vs 51.95±10.4, p=0.332). Six patients required operative intervention to address complications. Five developed infections: three had debridement, and 2 required implant removal and reimplantation.

Osseointegration does confer significant sustained mobility and quality of life improvement for wheelchair bound transfemoral amputees. All 9 K0 patients had statistically improved mobility and QOL after osseointegrated reconstruction. This supports osseointegration as an effective rapid and long-term rehabilitation alternative for patients who have the neurologic and muscular capacity to walk but are unable due to issues related to their TSP.


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Patients with above knee amputation (AKA) often experience poor socket fit exacerbated by minor weight changes, sweating, and skin problems. A transcutaneous, press-fit distal femoral intra-medullary device was designed in 1999, such that the distal external aspect serves as a hard point for AKA prosthesis attachment. The implant is placed in a retrograde fashion, followed 6-8 weeks later by stomatisation and connected via direct extention to an AKA prosthesis. Thirty-seven patients with 39 limbs (30 males, 7 females) underwent two-stage prosthesis implantation with the Endo-Exo Femurprosthesis (EEFP) in Germany between 1999 and January 2008. Their indications for surgery were persistent AKA prosthesis socket difficulties with absence of major comorbid physical or mental illnesses. The patients were followed clinically and radiographically for a minimum of 2 years. Assessments included patient satisfaction ratings, functional surveys, pain scores, and oxygen consumption. Fifty-four percent of patients needed at least one revision (20/37); 80% were minor (16/20) and 20% were major (4/20). Most of the minor revisions were due to soft tissue stomal irritation and occurred prior to a design change in the prosthesis. 2 patients sustained traumatic, peri-trochanteric fractures that were treated operatively proximal to the implant, with retention of the implant. 4 implants were explanted due to infection or prosthesis fracture and 2 of these (50%) were later reimplanted successfully. Overall, 94.9% (37/39) limbs had ultimate EEFP implant success. All functional assessments showed statistically significant improvement over baseline except oxygen consumption, which trended toward improvement. This procedure demonstrated a high degree of functional improvement for the majority of AKA patients treated. Despite an initially high revision rate, the EEFP prosthesis achieves an extremely high rate of successful reconstruction for trans-femoral amputees when more traditional options have failed and therefore warrants further scientific study


Orthopaedic Proceedings
Vol. 104-B, Issue SUPP_5 | Pages 9 - 9
1 Apr 2022
Lu W Oomatia A Muderis MA
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Introduction. Advantages of osseointegration have been reported to include improved functional mobility, better osseoperception, improved comfort, reduced pain, better biomechanical alignment and gait, which all lead to a less restricted lifestyle and significantly improved quality of life. A major concern of the Osseointegrated approach lies in the risk of infections occurring from the permanent transcutaneous opening often referred to as the stoma. Materials and Methods. Detailed analysis has been performed on all osseointegration surgeries performed by the Osseointegration Group of Australia and it's affiliates since 2010. All events leading to a re-admission and subsequent re-operation have been identified through hospital operation records and pooled together for meta-analysis. Events identified include: revision of implants, periprosthetic fracture fixation, surgical debridement due to infections, neurectomies and soft- tissue refashioning. Results. Majority of these cases were performed following the single-stage protocol. Among all cases, there were a total of 399 re-operation events recorded which occurred among 163 patients, indicating a high recurrence rate among the same patients. We recorded a total of 112 washouts, 93 neurectomies, 117 soft tissue refashions, 53 implant revisions and 24 periprosthetic fracture fixations. Conclusions. In this study, we have identified several addition possible reasons in which an osseointegration patient may need to be re-admitted into hospital for additional surgery. It was identified that through the implementation of improved surgical techniques and rehabilitation protocols, the rate of several of these re-operation events can be largely reduced, thus improving the overall outcomes of patients undergoing osseointegration surgery


Orthopaedic Proceedings
Vol. 105-B, Issue SUPP_10 | Pages 15 - 15
1 Jun 2023
Oomatia A Lu W Al Muderis M
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Introduction. Osseointegration has emerged as a promising alternative to rehabilitating with a traditional socket mounted prosthesis. Advantages have been reported to include improved functional mobility, better osseoperception, improved comfort, reduced pain, better biomechanical alignment and better gait, which all lead to a less restricted lifestyle and significantly improved quality of life. A major concern of the Osseointegrated approach lies in the risk of infections occurring from the permanent transcutaneous opening often referred to as the stoma. Several systematic reviews have indicated that the occurrence of minor infections can be quite common, serious complications are reported to be rare. In addition to commonly anticipated complications including fractures, surgical debridements or revisions, we have identified several significant events in which a patient may require to be readmitted and go through additional surgery. The objective of this study is to examine the rate of occurrence and reports on the best management practices of serious complications across a multi-centre review of more than 1000 osseointegration surgeries. Materials & Methods. A detailed analysis has been performed on all osseointegration surgeries performed by the Osseointegration Group of Australia and it's affiliates between since 2010. The majority of surgeries took place in Australia, the United States, the Middle East as well as in Europe. All events leading to a re-admission and subsequent re-operation have been identified through hospital operation records and pooled together for meta-analysis. Events identified include: revision of implants, periprosthetic fracture fixation, surgical debridement due to infections, neurectomies and soft- tissue refashioning. Results. Over 800 surgeries have been identified with a minimum 12-month follow-up time and included in this study. These included tibial, femoral and humeral, radial-ulnar and transpelvic osseointegration cases. The majority of these were performed using a single stage protocol. While general complications such as infection and soft tissue refashioning are common, serious events such as revision and fracture are rare. Interestingly, the rate of debridements and soft-tissue refashions were found to be higher among patients who were operated using a two-stage surgery. Among all cases, there were a total of 399 re-operation events recorded which occurred among 163 patients, indicating a high recurrence rate among the same patients. We recorded a total of 112 washouts, 93 neurectomies, 117 soft tissue refashions, 53 implant revisions and 24 periprosthetic fracture fixations. Conclusions. Many events leading to readmission after the primary surgery may not necessarily be graded as a complication of the osseointegration technique. This study has identified several addition possible reasons in which an osseointegration patient may need to be re-admitted into hospital for additional surgery. It was identified that through the implementation of improved surgical techniques and rehabilitation protocols, the rate of several of these re-operation events can be largely reduced, thus improving the overall outcomes of patients undergoing osseointegration surgery


Orthopaedic Proceedings
Vol. 105-B, Issue SUPP_10 | Pages 14 - 14
1 Jun 2023
Ong G Hoellwarth J Oomatia A Al Muderis M
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Introduction. Approximately 2,000 Skeletal transcutaneous osseointegration (STOI) procedures have been performed worldwide as of 2020, more than half of which have been performed by the Osseointegration Group of Australia using a press-fit technique with either ILP or OPL implant designs. Despite the consistently demonstrated clinical benefits, concerns regarding potential complications following STOI have slowed its widespread adoption. As more patients are followed for a longer period of time, longitudinal studies have confirmed complication rates are very acceptable, similar to those of total ankle and total elbow replacements. One of the major risk category is implant removal. The primary goal of this study was to investigate the complications and technical issues associated with transtibial osseointegration implant removal due to any cause. The focus here will be on the press-fit ILP and OPL implants, including the indications for removal and patient outcomes following removal. Materials & Methods. A review of our osseointegration registry between November 2010 and March 2022 was performed. Inclusion criteria were patients who have undergone removal of a transtibial osseointegration implant due to any cause. Selected patients either had a follow-up of at least two years or had their index osseointegration surgery at least two years prior to when the study was performed. Patients who have had osseointegration at other anatomic levels, and patients who underwent simultaneous total knee replacement with transtibial osseointegration were excluded from the registry search. Results. There were a total of 148 transtibial osseointegration procedures performed during the study period, with 97 (65.5%) performed in males and 51 (34.5%) performed in females. The average age at first stage osseointegration procedure is 50.4 years (range 16.8–87.9, SD 14.1). In the study cohort of 22 cases requiring implant removals, 12 (54.5%) were male and 10 (45.5%) were female. The average age at first stage osseointegration procedure in this cohort is 51.3 (range 37.4–82.6, SD 10.7) and average BMI 30.3 (range 21.9–40.9, SD 5.8). Although men comprised the majority of removals, women had a greater relative risk (Fisher exact test p=0.032). The average duration from time of STOI to removal was 2.6 years (range 0.1–6.8, SD 1.9) within this 11.5 year follow-up period. The most frequent indication was infection (54.6%, n=12) followed equally by pain (13.6%, n=3), aseptic loosening (13.6%, n=3) and implant fracture (13.6%, n=3), and lastly failure to integrate (4.6%, n=1). Conclusions. Of the 22 removals, 12 were reimplanted at the same anatomical level (10 were reimplanted within 6 months, 1 within 12 months, and 1 within 24 months). 11 of these cases currently wear their prosthetic legs for more than 13 hours daily. 1 case was recently reimplanted and still completing their loading program. Of the patients who were not reimplanted at the same anatomical level, 1 required proximal amputation with transfemoral osseointegration. 3 patients converted to traditional socket prostheses (TSP) due to pain, and 1 underwent proximal amputation and converted to TSP due to infection. 3 cases are currently awaiting transtibial osseointegration reimplantation, and 1 patient was deceased. 1 patient was lost to follow-up


Orthopaedic Proceedings
Vol. 94-B, Issue SUPP_XXI | Pages 94 - 94
1 May 2012
S. C C. P N. K N. F G. B
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Problems associated with soft tissues of the stump and attachment of prosthetic devices for amputees remains a considerable problem. These problems are associated with the transmission of load through the soft tissues of the stump and difficulty in attaching the prosthetic device. Several devices have an osteointegrated transcutaneous prosthesis attached to the residual bone onto which an exo-prostheses is secured thereby transmitting load directly through the skeleton. Infection of these devices is a key issue. A biomimetic intraosseous transcutaneous device for amputees known as ITAP has been developed which is based on deer antler morphology. We have shown that in deer antlers the dermal and epithelial tissues are tethered by collagen fibres which originate from pores in the bone. In a caprine model where the soft tissue interface of ITAP is porous, dermal and epithelial integration occurs creating a seal and preventing infection. In two clinical veterinary cases an ITAP implant has been successfully used in trans-radial canine amputees. A human trans-humeral amputee who previously could not wear their exo-prosthesis has been treated with ITAP. The surgery was single stage procedure and involved the insertion of an uncemented intramedullary stem into the residual humerus. A porous flange structure positioned adjacent to the dermal tissue which had most of the hypodermis removed was used to promote soft tissue ingrowth. At two years' post-operation the skin seal has been maintained, there has been no incidence of infection, the patient wears their exo-prostheses for over 8 hours a day and has an almost complete range of shoulder motion. The use of ITAP device in selected cases may revolutionise the way amputees are surgically treated, lead to increased activity levels and more normal life styles in these patients


Orthopaedic Proceedings
Vol. 100-B, Issue SUPP_7 | Pages 18 - 18
1 May 2018
Phillip R Muderis MA Kay A Kendrew J
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Advances in military surgery have led to significant numbers of soldiers surviving with bilateral above knee amputations. Despite advances in prosthetic design and high quality rehabilitation not all amputees succesfully ambulate. Five patients (10 stumps) with persisting socket fit issues were selected for osseointegration (OI) using a transcutaneous prosthesis with press-fit fixation in the residual femur. Prior to surgery all five were primarily/exclusively wheelchair users. Follow up was from 7 to 25 months (mean 12.2). There were no deaths, episodes of sepsis or osteomyelitis. There was one proximal femoral fracture secondary to a fall. One stump required soft tissue refashioning. Cellulitis needing oral antibiotics occurred in four cases. Functional improvement occurred in all cases with all currently primarily prosthetic users, the majority all day users. Three patients are still completing rehabilitation. Six minute walk tests (SMWT) improved by a mean of 20%. Three are now graded mobility SIGAM F (normal gait) and two SIGAM D-b (limited terrain; with one stick). This cohort suggests that OI may have a role in the treatment of military blast amputees. A larger scale clinical evaluation is planned in the UK blast related amputee population to further establish the benefits and risks of this technique


Orthopaedic Proceedings
Vol. 99-B, Issue SUPP_7 | Pages 71 - 71
1 Apr 2017
Mont M
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The prevalence of knee osteoarthritis (OA) in The United States is approximately 40 million cases, and this number is expected to rise to 60 million by the year 2020. Multiple non-operative treatment options are available for patients, including bracing. Braces can also be used for “pre-habitation” prior to total knee arthroplasty (TKA), after TKA, after traumatic sports injuries, and in neurologic patients. Although, the AAOS recommendations for brace use for treatment of knee osteoarthritis (OA) are “inconclusive”, recent studies have shown improved functional outcomes with the use of off-loader braces for the treatment of uni-compartmental knee OA. In addition, supplemental modalities such as transcutaneous electrical nerve stimulation (TENS) and neuromuscular electrical stimulation (NMES) have demonstrated improved subjective and functional outcomes. These off-loader braces and supplemental modalities are easy to use, may decrease pain, delay TKA, and improve clinical outcomes following surgery. In addition, they may decrease the use of other costly knee OA treatment options such as pain medications and intra-articular injections


The Bone & Joint Journal
Vol. 106-B, Issue 3 | Pages 293 - 302
1 Mar 2024
Vogt B Lueckingsmeier M Gosheger G Laufer A Toporowski G Antfang C Roedl R Frommer A

Aims

As an alternative to external fixators, intramedullary lengthening nails (ILNs) can be employed for distraction osteogenesis. While previous studies have demonstrated that typical complications of external devices, such as soft-tissue tethering, and pin site infection can be avoided with ILNs, there is a lack of studies that exclusively investigated tibial distraction osteogenesis with motorized ILNs inserted via an antegrade approach.

Methods

A total of 58 patients (median age 17 years (interquartile range (IQR) 15 to 21)) treated by unilateral tibial distraction osteogenesis for a median leg length discrepancy of 41 mm (IQR 34 to 53), and nine patients with disproportionate short stature treated by bilateral simultaneous tibial distraction osteogenesis, with magnetically controlled motorized ILNs inserted via an antegrade approach, were retrospectively analyzed. The median follow-up was 37 months (IQR 30 to 51). Outcome measurements were accuracy, precision, reliability, bone healing, complications, and patient-reported outcome assessed by the Limb Deformity-Scoliosis Research Society Score (LD-SRS-30).


Orthopaedic Proceedings
Vol. 98-B, Issue SUPP_17 | Pages 36 - 36
1 Nov 2016
Barrack R
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Tourniquet use in total knee arthroplasty (TKA) is convenient for the surgeon and provides a bloodless field for expeditious surgery and a dry field for cementation, but can best be described as an orthopaedic tradition. It is logical for complex anatomy of ligament, nerve, and vessel surgery but it may not be necessary for TKA. In one recent randomised trial, the absence of the tourniquet was not found to affect the quality of cement fixation. There are numerous potential downsides to the use of a tourniquet including decrease range of motion, delayed recovery, increased pain, wound complications, micro-emboli, neuropathy, and increased VTE. There are also a number of complications associated with the use of a tourniquet including arterial thrombosis, skin irritation below the tourniquet, post-operative hyperemia, blood loss, less accurate intra-operative assessment, and it complicates intravenous drug administration. Studies of range of motion have shown that when there is a difference noted, the range of motion is consistently better without tourniquet use. When a tourniquet is utilised it has been found to be advantageous to only use the tourniquet for a minimal amount of the case, typically when cementing is performed. Functional strength has also been found to be improved without the use of a tourniquet. In a recent randomised trial, tourniquet use was associated with decreased quad strength at 3 weeks that persisted at 3 months. This was attributed to muscle damage, tourniquet-induced ischemia, and compressive injury. Increased peri-operative pain has also been reported in randomised trials associated with the use of a tourniquet. Edema, swelling, and limb girth issues have also been noted to be associated with tourniquet use. Exsanguinating a limb will result in swelling approximately 10% of the original volume half due to a return of blood, and half due to reactive hyperemia. Longer tourniquet times are also associated with increased wound drainage and more wound hypoxia as measured by transcutaneous oxygen levels. Tourniquet use has also been associated with embolic phenomenon with several times greater risk of large emboli. In one study where quantitative MRI was utilised on both thighs after unilateral total knee replacement with and without a tourniquet, the tourniquet group showed more atrophy with a loss of 20% of the volume compared to the normal side in total knees performed with a tourniquet which also performed clinically worse. There is a small but substantial risk of arterial thrombosis particularly in patients that have atherosclerotic plaque. Ironically there is a risk of increased post-operative blood loss due to the post-tourniquet “blush” as the blood pressure and pain increase hours after a surgical procedure is completed. There is also difficulty in identifying and coagulating posterior and lateral geniculate vessels with the components in place. Utilizing a tourniquet also interferes with intra-operative assessment of patella tracking, range of motion, ligament stability, and gap balancing. Randomised clinical trials have concluded that there is less pain and quicker recovery without the use of a tourniquet. There have also been reports of less swelling, increased range of motion, less analgesic use and better clinical outcome when a tourniquet is not utilised. A meta-analysis of systematic reviews favored not utilizing a tourniquet due to the decrease in complication rate and the improvement in clinical results. While it is standard practice in the US to utilise a tourniquet, the strong consensus of the literature on the subject favors either not using a tourniquet or minimizing the use of a tourniquet for the period of time necessary for a very dry field for cement fixation


Orthopaedic Proceedings
Vol. 96-B, Issue SUPP_8 | Pages 76 - 76
1 May 2014
Mont M
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Traditionally, arthritis is a disease which generally affects the elderly population. However, the incidence in young patients is well described and is increasing with the ever-growing obese population. Currently, the non-surgical treatment of osteoarthritis consists of corticosteroid injections, hyaluronic acid injections, weight loss, physical therapy, bracing, orthotics, narcotics, and non-steroidal anti-inflammatory drugs (NSAIDS). Oral medications (NSAIDS, tramadol, and opioids) can provide effective pain relief. Improvement with NSAIDs has been reported to be 20% relative to baseline, with better improvements seen with selective cox-2 inhibitors, which also have reduced gastrointestinal and renal toxicity. Additionally, the recent AAOS guidelines strongly recommend using NSAIDs or tramadol for pain relief. Although narcotics are effective analgesics, their use in young arthritic patients can potentially predispose individuals to future opioid dependency, and thus should be used sparingly. The primary purpose of physical therapy is to improve range of motion, strengthen muscles, and improve proprioception. Currently, the AAOS strongly recommends that patients undergo self-management programs, strengthening, low-impact aerobic exercises, and neuromuscular education. Similarly, they moderately recommended that patients with a BMI ≥ 25 undergo weight loss for symptomatic arthritis. Bracing options consist of the following: off-loader braces and transcutaneous nerve stimulation braces. These work to either off-load pressure in the knee or to scramble small nerve pain sensation, respectively. Corticosteroid injections are used to minimise pain and reduce inflammation in the joint associated with arthritis. However, their long-term repetitive use in young patients is not recommended, and current AAOS guidelines are inconclusive on their effectiveness. Additionally, the AAOS guidelines strongly recommend against the use of acupuncture, glucosamine/chondroitin, and hyaluronic acid injections


Orthopaedic Proceedings
Vol. 94-B, Issue SUPP_XXXIX | Pages 77 - 77
1 Sep 2012
Aschoff H McGough R
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Patients with above knee amputation face many challenges to mobility including difficulty with socket fit and fatigue due to high energy consumption. The aim of the Endo - Exo-Femur Prosthesis is to avoid problems at the interface between the sleeve of the socket-prosthesis and the soft tissue coat of the femur stump which often impedes an inconspicuous and harmonic gait. In 1999 we began using a transcutaneous, press-fit distal femoral intramedullary device whose most distal external aspect serves as a hard point for AKA prosthesis attachment. The bone guided prosthesis enables an advanced gait via osseoperception and leads to a decreased oxygen consumption of the patient. 43 patients were implanted between 1999 and 2009. Four of the 43 required removal:one for intramedullary infection, one due to stem fracture (replaced), and the two for soft tissue infection. The remaining 39 original prostheses remained. Two pertrochanteric fractures occurred, treated with ORIF. Two bilateral procedures were performed. Initially, twenty patients had chronic soft tissue irritation requiring debridement. This completely resolved by changing the connecting components to a highly polished cobalt chrome. All patients reported increased comfort when compared to socket use. The following additional advantages were observed: improved mobility and endurance, improved proprioception, decreased time required for prosthetic donning, lack of concern regarding changing body weight, and the absence of skin irritation. All patients reported an improvement in sense of position and tactile sensation, leading to an improved gait pattern. Subjectively, the EEFP represents a significant improvement in terms of comfort. Since the introduction of high-gloss polished surfaces, soft tissue irritation is largely eliminated. Intramedullary infection has been negligible, as osseointegration seals the medullary cavity. In summary, the EEFP appears to be an attractive option in transfemoral amputees


Orthopaedic Proceedings
Vol. 94-B, Issue SUPP_XL | Pages 27 - 27
1 Sep 2012
Carr C Tadross R Mahfouz M
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Introduction. Kinematics tracking is the process by which the motion of the joints is studied. This motion consists of relative rotation and translation of the joint bones. Joint motion analysis is used in diagnosis of joint pathology, as well as studying the normal joint function. Currently, fluoroscopy is used in joint kinematics tracking. We are researching the use of pulse-echo A-mode ultrasound for the bone motion tracking instead of the fluoroscopy to avoid its radiation. In this work we performed feasibility study using simulation, and concluded that it is feasible to perform knee motion tracking with accuracy of 2 mm. Methods. The idea of the proposed system is to attach a number of single-element ultrasound transducers to a brace as shown in Figure 1. This brace will have a commercially available optical or electromagnetic tracking system's probe attached to it to track the global motion of the brace. The ultrasound transducers will be responsible for transcutaneously detecting points over the surface of the bone. The bone's echo extracted from each signal at each transducer will be registered in the optical or electromagnetic tracker's coordinate frame to create a set of points acquired over the surface of the bone. These points represent the bone's position at that point of time. A 3D model of the bone is then registered to these points using the iterative closest point method (ICP) to estimate the bone's position. At each tracking step, the 3D model will be at a position close to the new position of the points set, because this process will be repeated at a rate of 100 Hz or more in order to ensure that the change in the bone's position between every two successive tracking steps is small enough to guarantee high tracking accuracy. In this work we simulated the mentioned process using real kinematics data obtained for a patient using fluoroscopy. 3D models of the proximal tibia and distal femur were segmented from CT scans of the patient's knee. These models were then moved using the kinematic data in incremental steps. Simulated points over the surface of the bones (simulating the points on the bone's surface to be acquired using ultrasound) were used to track the bones' simulated motion using another set of the bones 3D models which move only according to the registration with the simulated points. In other words, the tracking models follow the simulated points' motion. Simulation was performed using deep knee bend kinematics data. Results. The simulation performed using 24 simulated ultrasound transducers for the femur and 18 for the tibia with the configuration shown in Figure 2. Accumulated tracking error of 0.02, and o.5 mm was obtained for the femur and tibia respectively. The tracking step error for the whole cycle is shown in the Figure 3. Conclusions. The tracking accuracy obtained from the simulation proves the feasibility of the proposed method for knee kinematics tracking. This motivated the start of implementation of the system to assess the real accuracy and performance of the proposed method