Extensor mechanism disruption in total knee arthroplasty (TKA) occurs infrequently but often requires surgical intervention. We compared two cohorts undergoing extensor mechanism allograft reconstruction, one group had an extensor mechanism rupture, and the other had a recurrent ankylosed knee. Thirteen consecutive patients with extensor mechanism disruption or ankylosis after TKA were treated. Two different types of extensor mechanism allografts were used: quadriceps tendon-patella-patella tendon-tibial tubercle, and Achilles tendon allograft(Fig1). Demographic factors, diagnosis at extensor failure, Knee Society clinical rating scores, radiographs, and patient satisfaction were recorded. The average time from extensor mechanism disruption to surgery was 6.6 months (range, 1-24 months). At a mean followup of 24 months (range, 6-46 months), all patients were community ambulators. None of the patients showed a postoperative extensor lag. Average postoperative maximum flexion was 97° (90-115°) for the ruptured group and 80° (75-90) for the ankylosed grup. All patients thought their functional status had improved, and 87% were satisfied with the results of the allograft reconstruction (Fig 2, 3, 4, 5). One patient had allograft failure due to recurrent infection after re-revision for sepsis. The total extensor mechanism allograft and Achilles tendon allograft both were successful in the treatment of the failed extensor mechanism and showed promising results for the treatment of the ankylosed knee

Introduction. Chronic ruptures of the quadriceps tendon after total knee arthroplasty (TKA) are rare but are a devastating complication. The objective of this study was to validate the use of fresh frozen total fresh quadriceps tendon allografts for quadriceps tendon reconstruction. The hypothesis of this work was that the graft was functional in more than 67% of cases, a higher percentage than the results of conventional treatments. Material – methods. We designed a continuous monocentric retrospective study of all patients operated on between 2009 and 2017 for a chronic rupture of the quadriceps tendon after TKA by quadriceps allograft reconstruction. The usual demographic and perioperative data and the rehabilitation protocols followed were collected. Initial and final radiographs were analyzed to measure patellar height variation. The main criterion was the possibility of achieving an active extension of the knee with a quadriceps contraction force greater than or equal to 3/5 or the possibility of lifting the heel off the ground in a sitting position. Results. 29 patients with 33 allografts were included; 3 iterative allografts were performed on ruptures of the initial transplant and 1 patient was grafted on both sides in one step. There were 21 women and 8 men with a mean age of 73 years, and a mean body mass index of 33 kg/m. 2. Ruptures occurred in 22 cases after chronic periprosthetic infection. Walking was allowed immediately in 29 cases, but free mobilization was delayed in 29 cases. Complications affected 22 cases, but the majority of complications were not related to allograft use (including infectious failures and periprosthetic fractures). After a mean follow-up of 52 months, 28 allografts were still in place, and 22 allografts were considered functional. The active quadriceps extension force was rated on average at 3.5/5. The average pre/post-operative patellar height differential was +2 mm. Discussion. This continuous series of 33 allografts is in line with recent publications on the subject. It confirms their negative impact on the functional outcome of the TKA. The complication rate is high but the specific complication rate is not prohibitive. Two thirds of transplants are functional in the long term. Early rehabilitation procedures can be used in these difficult patients with encouraging results. The management of chronic ruptures of the quadriceps tendon after TKA by quadriceps allograft must be part of the current therapeutic options

Introduction. A deficient abductor mechanism leads to significant morbidity and few studies have been published describing methods for reconstruction or repair. This study reports the reconstruction of hip abductor deficiency using human allograft. Methods. All patients were identified as having deficient abductor mechanisms following total hip arthroplasty through radiographic assessment, MRI, clinical examination and intra-operative exploration. All patients underwent hip abductor reconstruction using a variety of human allografts including proximal humeral, tensor fascia lata, quadriceps and patellar tendon. The type of allograft reconstruction used was customized to each patient, all being attached to proximal femur, allograft bone adjacent to host bone, with cerclage wires. If a mid-substance muscle rupture was identified an allograft tendon to host tendon reconstruction was performed. Results. Allograft reconstruction was performed in 15 patients over 18 months. One patient had an abductor deficiency after a primary total hip. All patients had an abductor lurch gait and positive Trendelenburg test preoperatively. Manual muscle strength testing showed significant weakness with a mean MRC grade of 3+/5. Peri-trochanteric pain was cited as a significant complaint in > 80 % of patients. Proximal humeral allografts, with rotator cuff, were used in 8 patients, 5 had tensor fascia lata and the remainder had patella with attached tendon allograft. The majority of patients had a reduction in pain and 8/15 (53%) increased their abductor strength by almost a full grade. A reduced lurch was observed in 10 (66%) patients and one patient re-dislocated after a failed revision for instability. Conclusion. To our knowledge, this is the largest reported series of allograft reconstruction for a deficient abductor mechanism following hip arthroplasty. A viable solution is demonstrated, with promising early results for a difficult problem, utilizing a straightforward technique with low morbidity

Chronic extensor mechanism insufficiency around TKA is a very challenging pathology to treat. An insufficient extensor mechanism negatively affects implant survival and patient outcomes. There are several risk factors for extensor mechanism disruption and the surgeon should be aware and avoid these problems in the perioperative period. In appropriately selected patients, reconstruction of the extensor mechanism is a valid option. Whole extensor mechanism and Achilles tendon allograft reconstruction of the deficient extensor mechanism have been proposed with good early published results. These reconstructions, however, are expensive and with time may stretch and lead to recurrence of an extensor lag. An alternative to allograft, is the use of Marlex mesh as popularised by Browne and Hanssen. This technique uses a knitted monofilament polypropylene mesh that is secured to the patient's native lateral tissue and covered by an appropriately dissected and distalised vastus medialis muscle. The technique can be used for both patellar and quadriceps tendon deficiencies and can be done with or without implant revision and is currently the treatment of choice at the presenter's institution. The surgeon should be aware of the complexity and limitations of these three reconstructive techniques

INTRODUCTION. Allograft reconstruction after resection of primary bone sarcomas has a non-union rate of approximately 20%. Achieving a wide surface area of contact between host and allograft bone is one of the most important factors to help reduce the non-union rate. We developed a novel technique of haptic robot-assisted surgery to reconstruct bone defects left after primary bone sarcoma resection with structural allograft. METHODS. Using a sawbone distal femur joint-sparing hemimetaphyseal resection/reconstruction model, an identical bone defect was created in six sawbone distal femur specimens. A tumor-fellowship trained orthopedic surgeon reconstructed the defect using a simulated sawbone allograft femur. First, a standard, ‘all-manual’ technique was used to cut and prepare the allograft to best fit the defect. Then, using an identical sawbone copy of the allograft, the novel haptic-robot technique was used to prepare the allograft to best fit the defect. All specimens were scanned via CT. Using a separately validated technique, the surface area of contact between host and allograft was measured for both (1) the all-manual reconstruction and (2) the robot-assisted reconstruction. All contact surface areas were normalized by dividing absolute contact area by the available surface area on the exposed cut surface of host bone. RESULTS. The mean area of contact between host and allograft bone was 24% (of the available host surface area) for the all-manual group and 76% for the haptic robot-assisted group (p=0.004). CONCLUSIONS. This is the first report to our knowledge of using haptic robot technology to assist in structural bone allograft reconstruction of defects left after primary bone tumor resection. The findings strongly indicate that this technology has the potential to be of substantial clinical benefit. Further studies are warranted

Purpose. The management of moderate to large engaging Hill-Sachs lesions is controversial and surgical options include remplissage, allograft reconstruction, and partial resurfacing arthroplasty. Few in-vitro studies have quantified their biomechanical characteristics and none have made direct comparisons. The purpose of this study was to compare joint stability and range of motion (ROM) among these procedures using an in-vitro shoulder simulator. It was hypothesized that all procedures would prevent defect engagement, but allograft and partial resurfacing would most accurately restore intact biomechanics; while remplissage would provide the greatest stabilization, possibly at the expense of motion. Method. Eight cadaveric shoulders were tested on an active in-vitro shoulder simulator. Each specimen underwent testing in 11 conditions: intact, Bankart lesion, Bankart repair, and two unrepaired Hill-Sachs lesions (30% & 45%) which were then treated with each of the three techniques. Anterior joint stability, ROM in extension and internal-external rotation, and glenohumeral engagement were assessed. Stability was quantified as resistance, in N/mm, to an anteriorly applied load of 70N. Results. Remplissage significantly increased joint stiffness compared to both defects (6.43.8 N/mm, p=0.01) and the allograft and partial resurfacing (p <= 0.04). No technique significantly surpassed the stability of the intact state (p>0.05). In adduction, the remplissage significantly reduced internal-external rotation compared to both defects (p <= 0.01), but only the 30% repair caused a significant change compared to the intact state (14.511.3 N/mm, p=0.05). In abduction, all repairs reduced rotation ROM compared to the Hill-Sachs defect (>= 8.24o, p <= 0.04), but none with respect to the intact condition (p >= 0.05). Remplissage had significantly less extension than either resurfacing procedure (>= 15.4o, p <= 0.02) and resulted in a greater reduction in extension ROM for 45% defects compared to 30% defects (11.918.91, p=0.06). All unrepaired lesions engaged during extension. None of the remplissage or allograft reconstructions engaged, however, 75% of partial resurfacing arthroplasties partially engaged. Conclusion. This study is the first biomechanical evaluation to directly compare three surgical procedures for engaging Hill-Sachs lesions. Each procedure enhanced stability; however, the enhancement provided by the resurfacing repairs more closely resembled the intact state. Remplissage of the 30% and the 45% defects improved stability and eliminated glenohumeral engagement but caused significant and progressive reductions in ROM. In comparison, both the allograft and partial resurfacing procedures re-established ranges of motion approaching those of the intact joint; however, the partial resurfacing could not fully prevent engagement. These findings indicate that the effects of each technique are not equivalent and further clinical and biomechanical studies are required

The infected joint arthroplasty continues to be a very challenging problem. Its management remains expensive, and places an increasing burden on health care systems. It also leads to a long and difficult course for the patient, and frequently a suboptimal functional outcome. The choice of a particular treatment program will be influenced by a number of factors. These include the acuteness or chronicity of the infection; the infecting organism(s), its antibiotic sensitivity profile and its ability to manufacture glycocalyx; the health of the patient; the fixation of the prosthesis; the available bone stock; and the particular philosophy and training of the surgeon. For most patients, antibiotics alone are not an acceptable method of treatment, and surgery is necessary. The standard of care for established infection is two stage revision with antibiotic loaded cement during the interval period and parental antibiotic therapy for six weeks. Single stage revision may have economic and functional advantages, however. We have devised a protocol that dictates the type of revision to be undertaken based on host, organism and local factors. Our protocol has included single stage revision using antibiotic loaded cement in both THA and TKA. This was only undertaken when sensitive organisms were identified pre-operatively by aspiration and appropriate antibiotics were available to use in cement. Patients with immunocompromise, multiple infecting organisms or recurrent infection were excluded. Patients with extensive bone loss that required allograft reconstruction or where a cementless femoral component was necessary were also excluded. Our algorithm was validated first in the hip and extended to infected TKA in 2004. This protocol has now been applied in over 100 TKA revisions for infection between 2004 and 2009. Our single stage revision rate is now over 25%. We continue to see a lower reinfection rate in these carefully selected patients, with high rates of infection control and satisfaction and better functional and quality of life scores than our two stage revision cases. Whilst our indications are arbitrary and not based on specific biomarkers, we present excellent results for selective single stage exchange. A minimum three year follow-up suggests that these patients have shorter hospital stays, higher satisfaction rates and better knee scores. An ongoing evaluation is in place. One stage revision arthroplasty for infection offers potential clinical and economic advantages in selected patients

The infected joint arthroplasty continues to be a very challenging problem. Its management remains expensive, and places an increasing burden on health care systems. It also leads to a long and difficult course for the patient, and frequently a suboptimal functional outcome. The choice of a particular treatment program will be influenced by a number of factors. These include the acuteness or chronicity of the infection; the infecting organism(s), its antibiotic sensitivity profile and its ability to manufacture glycocalyx; the health of the patient; the fixation of the prosthesis; the available bone stock; and the particular philosophy and training of the surgeon. For most patients, antibiotics alone are not an acceptable method of treatment, and surgery is necessary. The standard of care for established infection is two-stage revision with antibiotic loaded cement during the interval period and parental antibiotic therapy for six weeks. Single stage revision may have economic and functional advantages however. We have devised a protocol that dictates the type of revision to be undertaken based on host, organism and local factors. Our protocol has included single stage revision using antibiotic loaded cement in both THA and TKA. This was only undertaken when sensitive organisms were identified pre-operatively by aspiration and appropriate antibiotics were available to use in cement. Patients with immunocompromise, multiple infecting organisms or recurrent infection were excluded. Patients with extensive bone loss that required allograft reconstruction or where a cementless femoral component was necessary were also excluded. Our algorithm was validated first in the hip and extended to infected TKA in 2004. This protocol has now been applied in over 100 TKA revisions for infection between 2004 and 2009. Our single stage revision rate is now over 25%. We continue to see a lower reinfection rate in these carefully selected patients, with high rates of infection control and satisfaction and better functional and quality of life scores than our two-stage revision cases. Whilst our indications are arbitrary and not based on specific biomarkers, we present excellent results for selective single stage exchange. A minimum three-year follow-up suggests that these patients have shorter hospital stays, higher satisfaction rates and better knee scores. An ongoing evaluation is in place. One-stage revision arthroplasty for infection offers potential clinical and economic advantages in selected patients

Acetabular reconstruction of extensive bone defect is troublesome in revision total hip arthroplasty (rTHA). Kerboull or Kerboull type reinforcement acetabular device with allobone grafting has been applied since 1996. Clinical results of the procedure were evaluated. Patients. One hundred and ninety-two consecutive revision total hip arthroplasties were performed with allograft bone supported by the Kerboull or Kerboull type reinforcement acetabular device from 1996 to 2009. There were 23 men and 169 women. Kerboull plates were applied to 18 patients, and Kerboull type plates to 174. The mean follow up of the whole series was 8 years (4–18years). Surgical Technique. The superior bone defect was reconstructed principally by a large bulky allo block with plate system. Medial bone defect was reconstructed by adequate bone chips and/or sliced bone plates. After temporally fixation of bulky bone block with two 2.0mm K-wires, it was remodeled by reaming to fit the gap between host bone and plate, followed by fixation to the iliac bone by screws. Finally, residual space of the defect between host bone and the fixed plated was filled up with morselized cancellous bones, bone chips, and/or wedged bony fragments with impaction. This method was sufficiently applicable to AAOS Typeâ�, II, and III bone defects. In case of AAOS Typeâ�£, the procedure was also available after repairing discontinuation between distal and proximal bones by reconstrusion plate or allografting with tibial bone plates or sliced femoral head. Results. Nine patients (4.7%) required revision surgery (infection 5, breakage 3, and malalignment 1). The plate breakage was observed in 8 joints (4.2%). Three patients had no symptoms after the breakage. Three required revision, but the other cases were carefully observed without additional surgical intervention. Ten-year survival rate by Kaplan-Meier method was 96.6% when the endpoint was set revision by asceptic loosning. Conclusions. This study indicated that acetabular allograft reconstructions reinforced by Kerboull or Kerboull type acetabular device were able to recover bone stock with anatomic reconstruction of femoral head center, thus providing satisfactory clinical results in middle term period

There is a difference between “functional instability” of a total knee arthroplasty (TKA) and a case of “TKA instability”. For example a TKA with a peri-prosthetic fracture is unstable, but would not be considered a “case of instability”. The concept of “stability” for a TKA means that the reconstructed joint can maintain its structure and permit normal motion and activities under physiologic loads. The relationship between stability and alignment is that stability maintains alignment. Instability means that there are numerous alignments and almost always the worst one for the loading condition. In the native knee, “instability” is synonymous with ligament injury. If this were true in TKA, then it would be reasonable to treat every “unstable TKA” with a constrained implant. But that is NOT the case. If the key to successful revision of a problem TKA is understanding (and correcting) the specific cause of the problem, then deep understanding of why the TKA is unstable is essential. A case of true “instability” then, is the loss of structural integrity under load as the result of problems with soft tissue stabilizing structures and/or the size or position of components. It is rare that ligament injury alone is the sole cause of instability (valgus instability invariably involves valgus alignment; varus instability usually means some varus alignment and compromised lateral soft tissues). There will be forces (structures) that create instability and forces (structures) that stabilise. There are three categories of instability: Varus-valgus or coronal: Assuming that the skeleton, implant and fixation are intact. These are usually cases that involve ligament compromise, but the usual cause is CORONAL ALIGNMENT, and this must be corrected. The ligament problem is best solved with mechanical constraint. Gait disturbances that increase the functional alignment problems (hip abductor lurch causing a valgus moment at the knee, scoliosis) may require attention of additional compensation with re-alignment. Plane of motion: Both fixed flexion contractures and recurvatum may result in buckling. The first by exhaustion of the quadriceps (consider doing quadriceps “lunges” with every step) and the second because recurvatum is usually a compensation for extensor insufficiency. The prototype for understanding recurvatum has always been polio. This is perhaps one of the most difficult types of instability to treat. The glib answer has been a hinged prosthesis with an extensor stop but there are profound mechanical reasons why this is flawed thinking. The patient with recurvatum instability due to neurologic compromise of the extensor should be offered an arthrodesis, which they will likely decline. The simpler problem of recurvatum secondary to a patellectomy will benefit from an allograft reconstruction of the patella using a modified technique. A common occurrence is obesity with patellofemoral pain, that the patient has managed with a “patellar avoidance” or “hyperextension gait”. Plane of motion instability is a problem of the EXTENSOR MECHANISM DEFICIENCY. Flexion instability. This results from a flexion gap that is larger than the extension gap, where a polyethylene insert has been selected that permits full extension but leaves the flexion gap unstable. These patients achieve remarkable flexion easily and early, but have difficulties with pain and instability on stairs, with recurrent (non-bloody) effusions and peri-articular tenderness. Revision surgery is necessary. Flexion instability may also occur with posterior stabilised prostheses. So-called “mid-flexion” instability is a contentious concept, poorly understood and as yet, not a reported cause for revision surgery distinct from “FLEXION INSTABILITY”. Flexion instability is a problem of GAP BALANCE

Massive bone loss on both the femur and tibia during revision total knee arthroplasty (TKA) remains a challenging problem. Multiple solutions have been proposed for small osseous defects, including morselised cancellous bone grafting, small-fragment structural allograft, thicker polyethylene inserts, and the use of modular augments attached to revision prosthetic designs. Large osseous defects can be treated with structural allografts, impaction bone-grafting with or without mesh augmentation, custom prosthetic components, and specialised hinged knee components. The metaphyseal area of the distal femur and proximal tibia is a particularly attractive option during revision TKA given that it is usually undamaged and well-vascularised. While multiple reconstructive options have been recommended, porous tantalum metaphyseal cones have the advantage of improved biologic fixation because of their high porosity (75–80%), interconnected pore space, and low modulus of elasticity (3 MPa) similar to that of cancellous bone. Such features allow tantalum cones to fill bone defects while tolerating physiological loads. Indications for porous tantalum metaphyseal cones include patients with Anderson Orthopaedic Research Institute Type 2B or greater defects. The surgical technique is simpler than structural allograft reconstructions with decreased preparation time, resulting in a possible decrease in infection rates. The modularity of porous tantalum metaphyseal cones also allows the surgeon to choose a size and position that best fits the individual defect encountered. Moreover, tantalum cones can be used with several revision systems. Short-term clinical follow up indicates that porous tantalum metaphyseal cones effectively provide structural support with the potential for long-term biologic fixation and durable reconstructions

The infected joint arthroplasty continues to be a very challenging problem. Its management remains expensive, and places an increasing burden on health care systems. It also leads to a long and difficult course for the patient, and frequently a suboptimal functional outcome. The choice of a particular treatment program will be influenced by a number of factors. These include the acuteness or chronicity of the infection; the infecting organism(s), its antibiotic sensitivity profile and its ability to manufacture glycocalyx; the health of the patient; the fixation of the prosthesis; the available bone stock; and the particular philosophy and training of the surgeon. For most patients, antibiotics alone are not an acceptable method of treatment, and surgery is necessary. The standard of care for established infection is two-stage revision with antibiotic-loaded cement during the interval period and parental antibiotic therapy for six weeks. Single-stage revision may have economic and functional advantages however. We have devised a protocol that dictates the type of revision to be undertaken based on host, organism and local factors. Our protocol has included single-stage revision using antibiotic-loaded cement in both THA and TKA. This was only undertaken when sensitive organisms were identified pre-operatively by aspiration and appropriate antibiotics were available to use in cement. Patients with immunocompromise, multiple infecting organisms or recurrent infection were excluded. Patients with extensive bone loss that required allograft reconstruction or where a cementless femoral component was necessary were also excluded. Our algorithm was validated first in the hip and extended to infected TKA in 2004. This protocol has now been applied in over 100 TKA revisions for infection between 2004 and 2009. Our single-stage revision rate is now over 25%. We continue to see a lower reinfection rate in these carefully selected patients, with high rates of infection control and satisfaction and better functional and quality of life scores than our two-stage revision cases. Whilst our indications are arbitrary and not based on specific biomarkers, we present excellent results for selective single-stage exchange. A minimum three-year follow up suggests that these patients have shorter hospital stays, higher satisfaction rates and better knee scores. An ongoing evaluation is in place. One-stage revision arthroplasty for infection offers potential clinical and economic advantages in selected patients

INTRODUCTION. Bone tumour resection and subsequent reconstruction remains challenging for the surgeon. Obtaining adequate margins is mandatory to decrease the risk of local recurrence. Improving surgical margins quality without excessive resection, reducing surgical time and increasing the quality of the reconstruction are the main goals of today's research in bone tumour surgical management. With the outstanding improvements in imaging and computerised planning, it is now a standard. However, surgical accuracy is essential in orthopaedic oncologic surgery (Grimmer 2005). Patient specific instruments (PSI) may greatly improve the surgeon's ability to achieve the targeted resection. Thanks to its physical support, PSI can physically guide the blade yielding to a better control over the cutting process (Wong, 2014). Surgical time might significantly be reduced as well when compared to conventional method or navigated procedure. Finally, reconstruction may gain in rapidity and quality especially when allograft is the preferred solution as PSI can be designed as well for allograft cutting (Bellanova, 2013). Since 2011, PSI have systematically been used in our institution for bone tumour resection and when applicable allograft reconstruction. This paper reports the mid- to long-term medical outcomes on a large series. MATERIALS AND METHODS. Between 2011 and 2016, we systematically used PSI to remove bone tumours in 30 patients. The pre-operative planning involved the tumour delineation drawn on MRI by the surgeon. The MRI and obtained tumour volume were transferred to the CT-scan by image fusion (co- registration). Cutting planes were positioned around the tumour including a safe margin. The PSI were designed to ensure a sufficient stability but kept thin enough to limit the bone exposure. The PSI was manufactured by 3D-printing in a biocompatible and sterilisable material. PSI has been intraoperatively to cut the bone with predetermined margins. Medical files were reviewed for large data collection: type, size and site of the tumour, pre-and post-operative metastatic status, bone and soft tissues resection margins, local recurrence, use of an allograft and a PSI for graft adjustment or not for the reconstruction, the fusion of the allograft when applicable, the follow-up time and early/late complications. RESULTS. Over a period of 5 years, 30 patients were operated on with PSI (10 osteosarcomas, 4 chondrosarcomas, 10 Ewing sarcomas and 6 other types of bone tumours). Mean follow-up was 27±20 months. 18 cases out of 30 have more than 2 years follow-up and 13 out of 30 have more than 3 years of follow-up. Mean operating time was 6h02±3h44. Mean size of the tumours was 8,4±4,7cm and location was the upper limb in 5 cases, inferior limb in 15 cases and the pelvis in 10 occurrences. Metastatic disease developed postoperatively in 5 patients. Surgical margins in the bone were R0 in all cases but one case where a R1 surgery was planned to preserve a nerve root. We did not observe any local recurrence in the bone. Within soft tissues, margins were classified as R0 in 28 patients and R1 in 2 patients. In 26 cases, an allograft was used to reconstruct the bone defect. In 23 of those patients, the allograft was selected by CT scan and cut using a PSI. In the 3 allografts cut free-handily, only one demonstrated a fusion. Of the 23 cut with a guide, 12 fused completely, 2 demonstrated a partial fusion and 9 were not fused at the last follow-up. At the last follow-up, 2 patients were dead of disease, 5 were alive with metastatic disease and 23 were alive without disease. DISCUSSION. Oncology is probably the field where PSI can bring the largest advantage when compared to the conventional procedure. Several papers have reported the use of PSI for bone tumour resection. All of them have shown very promising results on in-vitro experiments (Cartiaux 2014), cadaver experiment (Wong 2012) or small clinical series (Bellanova 2013, Gouin, 2014). None of these papers report a large patient series associated with a clinically relevant follow-up. This series is the first mid- to long-term follow-up series involving PSI tumour surgery. These results are showing strong evidences of clinical improvements. It comes into contradiction with PSI for total knee arthroplasty where controversial results on the patient's outcome has been reported (Thienpont 2014). R0 margin has been systematically obtained for all bone cuttings, and local recurrence has been strongly decreased (3%) when compared to the usual recurrence rates published in the literature (from 15% to 35% according to the location). Allograft fusion seems improved as well thanks to the shape-matching of the selected allograft and a close contact between host and allograft at bony junctions. With a longer follow-up, these evidences should be stronger to definitely make PSI the best option for bone tumour resection

Aim:. Historically, anterior decompression followed by posterior fusion has been the surgical management of choice in spinal tuberculosis. Due to theatre time being at a premium, we have evolved to performing anterior only debridement, allograft strut reconstruction and instrumentation for tuberculosis in the adult thoracic spine. The aim of this study is to review the safety and the efficacy of this treatment. Methods:. Twenty-eight adult thoracic tuberculosis patients were identified where anterior only surgery had been performed. These were all in the mid-thoracic spine as circumferential surgery is still favoured in thoracolumbar disease. The surgery was performed by a single surgeon at a tertiary hospital. Following transthoracic aggressive debridement, allograft humeral shafts were cut to size and inserted under compression and the spines instrumented with the use of screw-rod constructs into the body above and below. A retrospective review of clinical notes and radiological studies was performed. Results:. Twenty-seven of the patients presented with altered neurology; 2 had only sensory changes while 25 presented with paraparesis; 22 of these patients were unable to walk. The average surgical time was 2 hours 20 minutes with a median blood loss of 726 ml. The majority of patients had 2 vertebral bodies involved and required an average of a 4 body fusion. Surgical complications included inadvertent opening of the diaphragm in 1 patient and 1 patient deteriorated neurologically post operatively. 21 of 28 patients recovered to independent mobility at their latest follow-up appointment. 1 patient showed no recovery, 3 had some motor recovery that was not useful, 1 had some sensory but no motor recovery. 16 of 28 patients have documented bony fusion with no evidence of instrumentation failure in any patients. Conclusion:. Anterior only debridement, allograft strut reconstruction and instrumented fusion for the treatment of thoracic spinal tuberculosis is a safe and effective alternative to circumferential surgery in the adult patient

The infected joint arthroplasty continues to be a very challenging problem. Its management remains expensive, and places an increasing burden on health care systems. It also leads to a long and difficult course for the patient, and frequently a sub optimal functional outcome. The choice of a particular treatment program will be influenced by a number of factors. These include the acuteness or chronicity of the infection; the infecting organism(s), its antibiotic sensitivity profile and its ability to manufacture glycocalyx; the health of the patient; the fixation of the prosthesis; the available bone stock; and the particular philosophy and training of the surgeon. For most patients, antibiotics alone are not an acceptable method of treatment, and surgery is necessary. The standard of care for established infection is two stage revision with antibiotic loaded cement during the interval period and parental antibiotic therapy for six weeks. Single stage revision may have economic and functional advantages however. We have devised a protocol that dictates the type of revision to be undertaken based on host, organism and local factors. Our protocol has included single stage revision using antibiotic loaded cement in both THA and TKA. This was only undertaken when sensitive organisms were identified preoperatively by aspiration and appropriate antibiotics were available to use in cement. Patients with immunocompromise, multiple infecting organisms or recurrent infection were excluded. Patients with extensive bone loss that required allograft reconstruction or where a cementless femoral component was necessary were also excluded. Our algorithm was validated first in the knee and extended to infected TKA in 2004. This protocol has now been applied in over 100 TKA revisions for infection between 2004 and 2009. Our single stage revision rate is now over 25%. We continue to see a lower reinfection rate in these carefully selected patients, with high rates of infection control and satisfaction and better functional and quality of life scores than our two stage revision cases. Whilst our indications are arbitrary and not based on specific biomarkers, we present excellent results for selective single stage exchange. A minimum three year follow-up suggests that these patients have shorter hospital stays, higher satisfaction rates and better knee scores. An ongoing evaluation is in place. One stage revision arthroplasty for infection offers potential clinical and economic advantages in selected patients

Introduction. When using press-fit stems in revision total knee arthroplasty (TKA), diaphyseal engagement optimizes stability. Attempts to maximize press fit may lead to periprosthetic fracture; however, the literature offers no guidance regarding the prevalence or management of this complication. The purpose of this study is to report the incidence, risk factors, and outcomes of these fractures. Methods. 634 Stemmed implants (307 femoral and 327 tibial) from 413 consecutive revision TKAs were reviewed. Immediate and 6 week post-operative radiographs were examined. Patient age, gender, stem length, diameter, and offset were evaluated as potential risk factors for fracture occurrence using a paired t-test for continuous and a chi-square analysis for categorical variables. Results. 15 Periprosthetic fractures (2.4%) were identified including two femoral (0.65%) and 13 tibial (4.0%). 10 Fractures were non-displaced, 3 had cortical displacement <2mm, and 2 were displaced >2mm. 1 Femur fracture was recognized and fixed intra-operatively with cables. 11 patients with non or minimally displaced fractures were allowed to bear weight as tolerated and 2 were protected for 2 weeks. 1 Displaced fracture was braced for 3 months, while the other was casted for concomitant extensor allograft reconstruction. All fractures showed radiographic evidence of healing and all patients were able to painlessly bear weight within 6 months. There was no evidence of implant migration at a mean of 15 months (range 3-47 months). 1 Patient developed recurrent infection at 10 months; no other complications were identified. With the sample size available for study, no significant differences in age (p=0.09), implant parameters (p=0.06-0.85) or gender (p=0.37) were detected between the fracture and non-fracture groups. Conclusions. Periprosthetic fractures occurred in approximately 2.4% of press-fit stems in revision TKA, more commonly in the tibia than femur. All fractures were managed non-operatively without complication or loss of prosthetic fixation

Prior to the 1970s, almost all bone sarcomas were treated by amputation. The first distal femoral resection and reconstruction was performed in 1973 by Dr Kenneth C Francis at the Memorial Sloan-Kettering Cancer Centre in New York. Since that time, limb-sparing surgery for primary sarcoma has become the mainstay of sarcoma surgery throughout the world. Initially, the use of mega-prostheses of increasing complexity, involving all the major long bones and both pelvic and shoulder girdles, was popularised. In the early 1980s, wide use of massive allograft reconstructions became widespread in both Europe and in multiple centres in the USA and UK. Since that time, increasing complexity in the design of prostheses has allowed for increasing functional reconstructions to occur, but the use of allograft has become less popular due to the development of late graft failures of patients survive past ten years. Fracture rates approaching 50% at 10 years are reported, and thus, other forms of reconstruction are being sought. Techniques of leg lengthening, and bone docking procedures to replace segmental bone loss to tumour are now employed, but the use of biological vascularised reconstructions are becoming more common as patient survivorship increases with children surviving their disease. The use of vascularised fibular graft, composite grafts and re-implantation of extra-corporeally irradiated bone segments are becoming more popular. The improvement in survivorship brought about the use of chemotherapy is producing a population of patients with at least a 65% ten year survivorship, and as many of these patients are children, limb salvage procedures have to survive for many decades. The use of growing prostheses for children have been available for some 25 years, first commencing in Stanmore, UK, with mechanical lengthening prostheses. Non-invasive electro-magnetic induction coil mechanisms are now available to produce leg lengthening, with out the need for open surgery. Whilst many of these techniques have great success, the area of soft tissue attachment to metallic prostheses has not been solved, and reattachment of muscles is of great importance, of course, for return of function. There are great problems in the shoulder joints where sacrifice of rotator cuff muscles is necessary in obtaining adequate disease clearance at the time of primary resection, and a stable shoulder construct, with good movement, has yet to emerge. Similar areas of great difficultly remain the peri-acetabular and sacro-iliac resections in the pelvis. Perhaps the real future of the art of limb salvage will be in the reconstruction of failed major joint replacements where there is great loss of bone stock, and already massive tumour prostheses are providing a salvage pathway for failed standard joint replacement. The final future for limb salvage, however, may not rest with increasing surgical complexity and innovation, but with the development of molecular biology and specific targeted treatments, according to the cytogenetics of a particular tumour. We are on the threshold of yet another quantum change in the approach to cancer management; just as chemotherapy brought a tremendous change in the 1970s, molecular biology is the frontier to make much of the current limb salvage surgery that is performed redundant

Adamantinoma are rare, low grade malignant, bone tumors, making up only 0.1–0.48 percent of primary malignant bone tumors. They occur predominantly in the long bones, especially the tibia. Histogenetically it is thought that it originates from embryological displacement of basal epithelium of the skin, although other hypotheses have been proposed. Clinically most patients present with swelling and possible bending of the tibia, painful or painless. It's often noticed in an earlier stadium, but symptoms are non-specific and have a slow progressive character. Median patient age is 25 to 35 years, with a range from two to 86 years. It is slightly more common in men than woman, with a ratio of 5:4. Occurrence in children is even rarer. A study by Van Rijn et al. finds only 119 references, and presents six more cases. Treatment is the same. An MRI-scan should be performed to check for metastasis, loco regional staging and for operative planning. Operative excision and reconstruction is necessary to prevent metastasis and maintain load bearing capacity. Generally these resections and reconstructions are done without objective measurements. The surgeon uses a rule of thumb, like a sculptor, or ruler approach to recreate the excised bone, either with allo- or autograft materials. An optimal fit, i.e. a minimal space between tibia and graft, is not always achieved, possibly resulting in pathological fractures. This risk of pathological fractures lengthens recovery time. The fractures elongate hospitalization time and recovery time and are a heavy burden to patients. Computer assisted surgery (CAS) systems, used for example in prosthesis placement, offer objective measurements in 3d space of hard structures with high accuracy. These can be used to produce an accurate copy of the resected bone. If the reconstruction accurately fits the bone defect that's left after the resection, it's likely that the occurrence of pathological fractures decreases. An adamantinoma in the tibia of a 12 year old boy was treated. Surgery consisted of hemicortical resection and inlay allograft reconstruction. The software used was the Orthomap navigation software (Stryker). A donor bone was supplied with help from the bone bank. The technical approach to the reconstruction was the planning of resection planes around the tumor. As the CT scale for both the patient and allograft bone is the same, the resection planes in the patient navigation setup could be copied to the allograft creation setup. Normal CAS setup was performed after first incision, with a tracker attached to the tibia. It was planned that a navigated bone saw would be used for the cutting. The tracker was attached to the saw with a new attachment, and calibrated in the universal calibration tool. During the surgery the oscillating saw proved to be impossible to navigate. The instrument calibration module was not able to accurately registered the saw, this despite accurate registrations in pre-operative testing. The CAS system was used however for accurately determining the saw planes. The planes were traced with the pointer tool. Then a non-navigated saw was used to perform both trapezoid shaped resections. A similar CAS setup was performed on the donor bone. The reconstruction was a good fit. The skin was closed in layers. Post-operative x-ray control was performed. Operation time was just over two hours. Currently the follow-up time is five months. There have been no complications and the control x-rays show good allograft ingrowth. While the original operation plan couldn't be performed the principle of computer assisted reconstruction has its merits. This was a proof of concept. The navigation was accurate to less than 1 mm, and the trapezoid resection shape guarantees a good fit. However the method of resection of the drawn planes by non-navigated bone saw was not accurate enough, because of the saw oscillations. There was improvement in operation time. With more accurate means of resection, as for example a computer controlled laser or water-jet, this type of reconstruction could have other very interesting applications

Treatment of Paprosky type 3A and 3B defects in revision surgery of a hip arthroplasty is challenging. In previous cases such acetabular defects were treated with massive structural allograft bone reconstructions using cemented all-polyethylene cups. In our department we started using custom made triflanged cups to restore the articulation of the hip. The triflanged cups were designed on the basis of CT-image analysis. We are using a new type of implant construction technique with additive technology. This is a production process consisting of ion beam sintering joining metal powder particles layer upon layer on the basis of a 3D model data. The production technique is similar to rapid prototyping manufacturing. 7 Patients have been treated with this new technique. The case studies will be presented with their clinical and radiographic follow-up. We think that additive technology is a breakthrough in treating this kind of severe acetabular defects