Two-stage closed sinus lift: a new surgical technique for maxillary sinus floor augmentation

Bone tissue atrophy may constitute a relative contraindication for implantation. The methods used in reconstruction of the alveolar ridge within the lateral section of the maxilla have been well known but not perfect. Presentation of the two-stage, closed sinus lift technique as well as efficacy evaluation of reconstruction of the alveolar ridge in the maxilla within its vertical dimension with the use of this technique. The total procedure was performed in 26 out of 28 patients qualified for the study. The height of the alveolar ridge at the site of the planned implantation was no <3 mm, the width of the ridge was no <5 mm. During the treatment stage 1 the sinus lift was performed for the first time. The created hollow was filled with allogeneic granulate. After 3–6 months stage 2 was performed consisting in another sinus lift with simultaneous implantation. The treatment was completed with prosthetic restoration after 6 months of osteointegration. In 24 out of 26 cases stage 1 was completed with the average ridge height of 7.2 mm. In stage 2, simultaneously with the second sinus lift, 26 implants were placed and no cases of sinusitis were found. In the follow-up period none of the implants were lost. The presented method is efficient and combines the benefits of the open technique—allowing treatment in cases of larger reduction of the vertical dimension and the closed technique—as it does not require opening of the maxillary sinus.

The effects of human amniotic fluid and different bone grafts on vertebral fusion in an experimental rat model

Objective

The high risk of nonunion represents a challenge in vertebral surgery, thus stimulating new strategies to improve fusion rates. We investigated the effect of 2 different bone grafts and amniotic fluid application on radiologically and histologically evaluated vertebral fusion in an experimental rat model.

Materials and methods

Forty-eight 24-week-old Sprague Dawley rats were included and assigned into 1 of 4 groups: allograft group, allograft plus human amniotic fluid group, demineralized bone matrix (DBM) group, or DBM plus human amniotic fluid group. After decortication and L4–L6 spinal fusion, study treatments were applied. Fusion in each rat was examined radiologically and histologically 8 weeks after the intervention.

Results

The group that received only allograft had better radiologic scores (median = 3.5; range = 3–4) when compared with the group that received only DBM (median = 2; range = 1–4) (P = 0.002); however, histologic scores did not differ. When amniotic fluid was added to the grafting, allograft-based treatments performed better than DBM-based treatments both on radiologic (median = 4; range = 3–4 vs median = 3; range = 3–4; P = 0.003) and histologic (median = 7; range = 6–7 vs median = 5; range = 3–6; P < 0.001) evaluation. Addition of amniotic fluid did not result in better outcomes in the rats that received DBM-based treatments but based on histologic evaluation, rats that received allograft-based treatments benefited from this application.

Conclusions

Amniotic fluid seems to have an enhancing effect on posterior spinal fusion, particularly when combined with allograft.

Development of an improved bone washing and demineralisation process to produce large demineralised human cancellous bone sponges

Shaped demineralised bone matrices (DBM) made from cancellous bone have important uses in orthopaedic and dental procedures, where the properties of the material allow its insertion into confined defects, therefore acting as a void filler and scaffold onto which new bone can form. The sponges are often small in size, <1.0 cm(3). In this study, we report on an improved bone washing and demineralisation process that allows production of larger DBM sponges (3.375 or 8.0 cm(3)) from deceased donor bone. These sponges were taken through a series of warm water washes, some with sonication, centrifugation, 100 % ethanol and two decontamination chemical washes and optimally demineralised using 0.5 N hydrochloric acid under vacuum. Demineralisation was confirmed by quantitative measurement of calcium and qualitatively by compression. Protein and DNA removal was also determined. The DBM sponges were freeze dried before terminal sterilisation with a target dose of 25 kGy gamma irradiation whilst frozen. Samples of the sponges were examined histologically for calcium, collagen and the presence of cells. The data indicated lack of cells, absence of bone marrow and a maximum of 1.5 % residual calcium.

The MRI appearances of cancellous allograft bone chips after the excision of bone tumours

Cancellous allograft bone chips are commonly used in the reconstruction of defects in bone after removal of benign tumours. We investigated the MRI features of grafted bone chips and their change over time, and compared them with those with recurrent tumour. We retrospectively reviewed 66 post-operative MRIs from 34 patients who had undergone curettage and grafting with cancellous bone chips to fill the defect after excision of a tumour. All grafts showed consistent features at least six months after grafting: homogeneous intermediate or low signal intensities with or without scattered hyperintense foci (speckled hyperintensities) on T1 images; high signal intensities with scattered hypointense foci (speckled hypointensities) on T2 images, and peripheral rim enhancement with or without central heterogeneous enhancements on enhanced images. Incorporation of the graft occurred from the periphery to the centre, and was completed within three years. Recurrent lesions consistently showed the same signal intensities as those of pre-operative MRIs of the primary lesions. There were four misdiagnoses, three of which were chondroid tumours. We identified typical MRI features and clarified the incorporation process of grafted cancellous allograft bone chips. The most important characteristics of recurrent tumours were that they showed the same signal intensities as the primary tumours. It might sometimes be difficult to differentiate grafted cancellous allograft bone chips from a recurrent chondroid tumour.

Case report and surgical technique

Anatomic variants of the peroneal tendons may cause tendon disorders. Moreover, there is a lack of evidence on how to address chronic tendon pathology when a variant of the peroneal tendons is causing the patient's symptoms. We present a patient with an uncommon peroneal muscle presentation: a single muscular belly dividing into both the peroneus longus and brevis tendons. After extensive debridement of tendinopathic tissue, primary repair or tenodesis was not possible; therefore a unique solution for this problem was performed, reconstructing both peroneal tendons using a semitendinosus allograft.

Validation of cold chain shipping environment for transport of allografts as part of a human tissue bank returns policy

Human tissue is shipped to surgeons in the UK in either a freeze-dried or frozen state. To ensure quality and safety of the tissue, frozen tissue must be shipped in insulated containers such that tissue is maintained at an appropriate temperature. UK Blood Transfusion Service regulations state "Transportation systems must be validated to show maintenance of the required storage temperature" and also state that frozen, non-cryopreserved tissue "must be transported… at -20 °C or lower" (Guidelines for the Blood Transfusion Services in the United Kingdom, 8th Edn. 2013). To maintain an expiry date for frozen tissue longer than 6 months, the tissue must be maintained at a temperature of -40 °C or below. The objective of this study was to evaluate and validate the capability of a commercially available insulated polystyrene carton (XPL10), packed with dry ice, to maintain tissue temperature below -40 °C. Tissue temperature of a single frozen femoral head or a single frozen Achilles tendon, was recorded over a 4-day period at 37 °C, inside a XPL10 carton with dry ice as refrigerant. The data demonstrate that at 37 °C, the XPL10 carton with 9.5 kg of dry ice maintained femoral head and tendon tissue temperature below -55 °C for at least 48 h; tissue temperature did not rise above -40 °C until at least 70 h. Data also indicated that at a storage temperature lower than 37 °C, tissue temperature was maintained for longer periods.

Surgical management of knee dislocations with ligament reconstruction associated with a hinged external fixator

INTRODUCTION

Knee dislocations are defined as ligament injuries involving at least two of the four most important knee ligaments. Results from recent studies have shown a tendency towards improvement of the functional outcomes with use of an articulated external fixator during the postoperative period following multiligament reconstruction. Our hypothesis was that good knee stability and early gain of range of motion could be achieved with the use of the external fixator after ligament reconstructions.

METHODS

Fourteen patients with knee dislocations were evaluated after multiligament reconstruction in association with use of a lateral monoplanar external fixator for six weeks. Reconstructions were performed using grafts from a tissue bank. Range of motion was measured after one, two, three, six, twelve months and at the final evaluation at a mean time of 49 months. The assessments were made using objective and subjective IKDC, Lysholm and Tegner scales.

RESULTS

The mean scores were 71.7 for the subjective IKDC score, 81.5 for the Lysholm score. No patient was able to return to previous Tegner score. Out of the 45 ligament reconstructions performed, only four failed during the follow-up time. The mean range of motion of the knee presented a progressive increase from the first to the twelfth month, from 67.8° to 115.7°. Two cases of superficial infection on the site of the external fixator pins were observed.

CONCLUSION

The use of an external fixator enabled early rehabilitation with range of motion gains starting from the first postoperative month, a low rate of reconstruction failure and minimal complications. Nevertheless, none of the patients returned to the level of activity prevailing prior to the injury.

LEVEL OF EVIDENCE

Level IV, retrospective therapeutic case series.

Autogenous bone harvest for implant reconstruction

Autogenous bone harvest is the gold standard for restoring deficiencies of the recipient site. A deficient site requires adequate grafting before placement of implants; therefore, proper understanding of the wide variety of grafting options is the key to successfully planned implant dentistry. This provides general dentists with a better understanding of autogenous bone harvest and the variety of techniques available to provide the best outcomes for the patient.

Results of reconstruction of massive irreparable rotator cuff tears using a fascia lata allograft

BACKGROUND

Despite the advances in surgical treatment options, massive rotator cuff (r-c) tears still represent a challenge for orthopedic surgeons. This study assesses the effectiveness of fascia lata allograft in reconstruction of massive and irreparable r-c tear and to evaluate the healing and functional outcomes.

MATERIALS AND METHODS

68 patients (38 men, 30 women, mean age 64.9 years) with massive or irreparable r-c tears were treated with placement of fascia lata allograft to fill the defect between February 2006 and February 2010. At 43 months followup they were evaluated clinically using the constant score, preoperatively and postoperatively. Magnetic resonance imaging (MRI) and ultrasound were used postoperatively, to assess the integrity of the allograft at the repair site. Postoperatively, standard rehabilitation protocol was followed with gradual restoration.

RESULTS

Postoperative constant score increased from 32.5 preoperatively to 88.7 postoperatively. The most important was the pain relief from 2.4 preoperatively to 14.1 postoperatively and range of motion. The results of the MRI were not reliable, but the ultrasound was satisfactory. Finally, there was no infection or rejection of the graft in any of the patients.

CONCLUSIONS

Despite advances in surgical methods, there is still not a universally accepted treatment for massive and irreparable rotator cuff tears, because the standard methods have dubious results, with excessive retear rates and poor outcomes, necessitating the need for new repair strategies. We documented significant clinical improvement using fascia lata allograft in the repair of massive irreparable r-c tear, acting as scaffold to bridge the defect, enhancing the healing at the repair site.

Functional and clinical evaluation at 5-year follow-up of a three-component prosthesis and osteochondral allograft transplantation for total ankle replacement

BACKGROUND

Severe ankle arthritis is a life-limiting condition which often requires surgery. Ankle arthroplasty via artificial or "biological" reconstruction is a viable option in those patients who are not comfortable with arthrodesis. More functional studies are needed to compare the performance and outcomes of the two function-preserving arthroplasties.

METHODS

In this study two groups of 10 patients affected by severe ankle arthritis were treated either with a 3-component ankle prosthesis or with bipolar fresh osteochondral allograft transplantation. Patients were evaluated pre-operatively and at 5-year follow-up. The American Orthopaedic Foot and Ankle Society score was used for clinical evaluation, and gait analysis for functional assessment. Activation pattern of lower limb muscles was obtained by surface electromyography (EMG). In each group, kinematic, kinetic, and EMG data were compared between pre-op and follow-up assessments, and also versus corresponding data from a 20 healthy subject control group. The median clinical score significantly increased between pre-op and follow-up from 53 to 74.5 in the transplantation and from 28.5 to 80 in the prosthesis group. Spatio-temporal parameters showed a statistically significant improvement in cadence and cycle time. Improvement of gait speed was also observed only in the prosthesis group. EMG patterns at follow-up were strongly correlated with the corresponding control data for both groups. Although no significant amelioration in the joints' range of motion was detected in either surgical procedure, preservation of the functional conditions at medium-term, along with significant improvement of the clinical score, may be considered a positive outcome for both techniques.

Cartilage allograft techniques and materials

Hyaline cartilage is avascular in nature, relying on surrounding synovial fluid for its nutrient supply. Lacking an inflammatory response, hyaline cartilage is unable to be repaired itself after injury. BMS technique allows reparative cartilage to be produced, taking the form of fibrocartilage. Fibrocartilage is weaker than hyaline cartilage. Various cartilage allograft materials are available for reparative techniques. The cartilage allograft materials discussed herein include fresh allograft transplantation, ACEM, and particulated juvenile articular cartilage.

Augmentation of bone healing in delayed and atrophic nonunion of fractures of long bones by partially decalcified bone allograft (decal bone)

BACKGROUND

Autograft from iliac crest is considered as gold standard for augmentation of bone healing in delayed and nonunion of fractures. Bone demineralized with 0.6N hydrochloric acid has shown to retain its osteoinductive capacity. We report the outcome of partially decalcified bone allograft (decal bone) in the treatment of delayed union and atrophic nonunions of bones.

MATERIALS AND METHODS

Twenty patients with clinicoradiological diagnosis of delayed union or atrophic nonunion of long bone fractures were included in this retrospective study. Patients at extreme of ages (<18 years and >60 years), pathological fractures, metabolic bone diseases, infected nonunion, hypertrophic nonunion and those having systemic illness like diabetes mellitus and on drugs that impair fracture healing were excluded from the study. Decal bone was prepared in the bone bank and maintained in department of orthopedics. Allografting was done in 20 patients of delayed union (9/20) and atrophic nonunion (11/20) of long bone fractures with mean age of 34 years (range 18-55 years). The bones involved were humerus (8/20), tibia (7/20) and femur (5/20). Fourteen patients underwent treatment in the form of internal fixation and allografting and six patients were operated with osteoperiosteal allografting.

RESULTS

Nineteen patients achieved union in mean time of 14.9 weeks range (range 8-20 weeks). Eight patients had serous discharge from the operative site that subsided in 11 days (range 4-21 days). One patient had pus discharge that required repeat debridement and antibiotics for 6 weeks. The fracture healed in 16 weeks.

CONCLUSION

The partially decalcified bone allograft is an effective modality for augmentation of bone healing without complication associated with autograft like donor site morbidity, increased blood loss and increase in the surgical time.

Successful orthotopic transplantation of short tracheal segments without immunosuppressive therapy

OBJECTIVES

Results of tracheal transplantation have been disappointing due to of ischaemia and rejection. It has been experimentally demonstrated that results of tracheal autograft/allograft transplantation were correlated with both graft length and revascularization method. Recently, we demonstrated that heterotopic epithelium-denuded-cryopreserved tracheal allograft (TA) displayed satisfactory immune tolerance. We aimed at evaluating the results of such allografts in orthotopic transplantation according to graft length and prior heterotopic or single-stage orthotopic revascularization in a rabbit model.

METHODS

Twenty New Zealand rabbits were used. Six females served as donors. Tracheal mucosa was mechanically peeled off and then the TAs were cryopreserved. Male recipients were divided into three groups receiving: (i) long TA segment with prior heterotopic revascularization (10-12 tracheal rings, n = 3); (ii) average TA segment with single-stage orthotopic revascularization (6-8 tracheal rings, n = 4); (iii) short TA segment with single-stage orthotopic revascularization (4-5 tracheal rings, n = 7). No immunosuppressive therapy was administered. Grafts were assessed bronchoscopically and upon death or sacrifice by macroscopic evaluation, histology and immunohistochemical staining for apoptosis.

RESULTS

Four animals were sacrificed from Day 33 to Day 220. The survival time of other recipients was 0-47 days (mean 19.6 ± 16.7 days). Aside from three animals that died from complications, all TA segments had satisfactory stiffness, were well vascularized, showed varying levels of neoangiogenesis and inflammatory infiltration devoid of lymphocytes, and showed evidence of only low levels of apoptosis. Varying degrees of fibroblastic proliferation originating from the lamina propria were observed in the lumen of all TAs and evolved over time into collagenized fibrosis in animals surviving over 45 days. Likewise, cartilage tracheal rings exhibited central calcification deposits, which started on Day 16 and increased over time. Epithelial regeneration was constantly observed. Intense fibroblastic proliferation led to stenosis in all animals from Groups (i) and (ii) but only one of seven animals from Group (iii).

CONCLUSIONS

Our results suggest that short segments of epithelium-denuded-cryopreserved TA may be reliable for tracheal transplantation in the rabbit model without problems related to graft stiffness or immune rejection. Before considering clinical applications, investigations should be conducted in larger mammals.

Reconstruction of the medial patellofemoral ligament: Evaluation of the clinical results of autografts versus allografts

OBJECTIVE

The purpose of the study was to evaluate the functional results after medial patellofemoral ligament (MPFL) reconstruction in patients using auto- and allograft.

PATIENTS AND METHODS

A retrospective study was conducted on 28 patients with recurrent patellar dislocation, with 13 patients (13 knees) undergoing MPFL reconstruction with hamstring autograft, and 15 patients (16 knees) with reconstruction surgery with allograft. The total group included 13 males and 15 females, with an age range of 15 to 38 years. The graft-related morbidity was studied and a clinical assessment was performed using the pre- and postoperative Kujala score. Associated complications were reported for each group. All the patients had more than 12 months of follow up.

RESULTS

No recurrent dislocations or graft related complications were reported in either group. The post-operative Kujala subjective knee score was 89.2 in the autograft group, and 92.6 in the allograft group (p >.05). One patient in the allograft group received a revision surgery due to poor positioning of anchors. Another patient in the allograft group had non-displaced patella fracture related to the bone tunnels and another patient had flexion deficit and needed mobilization under anesthesia.

CONCLUSION

There were no significant differences between both groups, and the results were comparable.

Lower extremity neuromuscular compensations during instrumented single leg hop testing 2-10 years following ACL reconstruction

BACKGROUND

This study compared lower extremity EMG activation and sagittal plane kinematics of subjects at a minimum of 2 years post-successful ACL reconstruction and rehabilitation during instrumented single leg hop testing.

METHODS

Comparisons were made based on subject responses to the following question, "compared to prior to your knee injury how capable are you now in performing sports activities"? Group 1=very capable, Group 2=capable, and Group 3=not capable. In addition to EMG (1000 Hz) and kinematic (60 Hz) data, subjective knee function, internal health locus of control, sports activity characteristics (intensity, frequency) pre-knee injury, and at follow-up were also compared.

RESULTS

Group 3 had lower perceived knee function, decreased perceived sports intensity, and more subjects with decreased sports activity intensity by two levels compared to pre-injury values. Perceived function scores, anterior laxity measurements and grades were similar between groups. During single leg hop propulsion and landing Group 1 (very capable) had greater involved lower extremity gluteus maximus and medial hamstring activation amplitudes than Group 3 (not capable). Perceived sports capability was related to better subjective knee function, and higher perceived sports activity intensity.

CONCLUSION

Neuromuscular compensations suggesting a hip bias with increased gluteus maximus and medial hamstring activation were identified at the involved lower extremity among most subjects who perceived high perceived sports capability compared to pre-injury status. These compensations may be related to a permanent neurosensory deficit, and its influence on afferent pathway changes that influence CNS sensorimotor re-organization.

A comparative evaluation of platelet-rich plasma in combination with demineralized freeze-dried bone allograft and DFDBA alone in the treatment of periodontal intrabony defects: A clinicoradiographic study

BACKGROUND

The aim of the present clinical trial was to compare PRP combined with a DFDBA to DFDBA mixed with a normal saline solution in the treatment of human intrabony defects.

MATERIALS AND METHODS

Twenty interproximal intrabony osseous defects in twenty non-smoking, healthy subjects diagnosed with chronic periodontitis were treated in this study. Ten subjects each were randomly assigned to the test group (PRP + DFDBA) or the control group (DFDBA + saline). Clinical and radiographic measurements were made at baseline, three month and at six-month evaluation.

RESULTS

The results at three and six months, when compared to the baseline, indicated that both treatment modalities resulted in significant changes in all clinical parameters (gingival index, bleeding on probing, probing depth, clinical attachment level and gingival recession; P < 0.01) and radiographic parameters (hard-tissue fill and bone-depth reduction; P < 0.01). However, the test group exhibited statistically significantly greater changes compared to the control group in plaque index at three months (P = 0.00), probing depth reduction at 6 months (P = 0.02) and the radiographic defect fill at 6 months (P = 0.01).

CONCLUSIONS

Treatment with a combination of PRP and DFDBA led to a statistically significantly greater improvement in plaque index at 3 months, probing depth at 6 months and radiographic defect fill at 6 months in intrabony periodontal defects as compared to DFDBA with normal saline.

A comparison of Biobrane™ and cadaveric allograft for temporizing the acute burn wound: Cost and procedural time

INTRODUCTION

In many circumstances early burn excision and autografting is unsafe or even impossible. In these situations, skin substitute dressings can be utilized for temporary wound coverage. Two commonly used dressings for this purpose are cadaveric allograft and Biobrane™.

MATERIALS AND METHODS

Five year retrospective cohort study evaluating upper extremity burns treated with temporary wound coverage (Biobrane™ or allograft). The primary outcome was to determine the impact choice of wound coverage had on operative time and cost. The secondary outcome was the need for revision of upper extremity debridement prior to definitive autografting.

RESULTS

45 patients were included in this study: 15 treated with cadaveric allograft and 30 treated with Biobrane™ skin substitute. Biobrane™ had a significantly lower procedure time (21.12 vs. 54.78 min per %TBSA excised, p=0.02) and cost (1.30 vs. 2.35 dollars per minute per %TBSA excised, p=0.002). Both techniques resulted in 2 revisions due to complications.

CONCLUSION

Biobrane™ is superior to cadaveric allograft as a temporizing skin substitute in the acute burn wound, both in terms of procedure time and associated cost. We believe that this is largely due to the relative ease of application of Biobrane™. Furthermore, given its unique characteristics, Biobrane™ may serve as a triage and transport option for severe burns in the military and mass casualty settings.

Multiple or metastatic clear cell chondrosarcoma: a case report

We report multiple synchronous clear-cell chondrosarcomas in a 43-year-old patient. The patient had a lesion in the right proximal humerus and in the left femoral condyle. Bone scintigraphy revealed increased uptake in both foci. Pathological analysis confirmed the diagnosis in both locations. In the proximal humerus, wide resection of the tumour was performed with allograft reconstruction of the joint with osteosynthesis. The femoral condyle was treated with curettage, phenolization, and cementation. Over a follow-up of 10 years no recurrence or metastasis was observed.

Review of experimental attempts of islet allotransplantation in rodents: Parameters involved and viability of the procedure

The purpose of the present study was to organize the parameters involved in experimental allotransplantation in rodents to elaborate the most suitable model to supply the scarcity of islet donors. We used the PubMed database to systematically search for published articles containing the keywords “rodent islet transplantation” to review. We included studies that involved allotransplantation experiments with rodents’ islets, and we reviewed the reference lists from the eligible publications that were retrieved. We excluded articles related to isotransplantation, autotransplantation and xenotransplantation, i.e., transplantation in other species. A total of 25 studies related to allotransplantation were selected for systematic review based on their relevance and updated data. Allotransplantation in rodents is promising and continues to develop. Survival rates of allografts have increased with the discovery of new immunosuppressive drugs and the use of different graft sites. These successes suggest that islet transplantation is a promising method to overcome the scarcity of islet donors and advance the treatment options for type 1 diabetes.

Upper extremity considerations for oncologic surgery

It was estimated that more than 3000 people would be diagnosed with a primary bone or joint malignancy and more than 11,000 people would be diagnosed with a soft tissue sarcoma in 2013. Although primary bone and soft tissue tumors of the upper extremity are infrequent, it is imperative that the clinician be familiar with a systematic approach to the diagnosis and treatment of these conditions to prevent inadvertently compromising patient outcome. With advances in chemotherapy, radiotherapy, tumor imaging, and surgical reconstructive options, limb salvage surgery is estimated to be feasible in 95% of extremity bone or soft tissue sarcomas.

autograft

BACKGROUND

Post-operative widening of tibial and/or femoral bone tunnels is a common observation after ACL reconstruction, especially with soft-tissue grafts. There are no studies comparing tunnel widening in hamstring autografts versus tibialis anterior allografts. The goal of this study was to observe the difference in tunnel widening after the use of allograft vs. autograft for ACL reconstruction, by measuring it with a novel 3-D computed tomography based method.

METHODS

Thirty-five ACL-deficient subjects were included, underwent anatomic single-bundle ACL reconstruction and were evaluated at one year after surgery with the use of 3-D CT imaging. Three independent observers semi-automatically delineated femoral and tibial tunnel outlines, after which a best-fit cylinder was derived and the tunnel diameter was determined. Finally, intra- and inter-observer reliability of this novel measurement protocol was defined.

RESULTS

In femoral tunnels, the intra-observer ICC was 0.973 (95% CI: 0.922-0.991) and the inter-observer ICC was 0.992 (95% CI: 0.982-0.996). In tibial tunnels, the intra-observer ICC was 0.955 (95% CI: 0.875-0.985). The combined inter-observer ICC was 0.970 (95% CI: 0.987-0.917). Tunnel widening was significantly higher in allografts compared to autografts, in the tibial tunnels (p=0.013) as well as in the femoral tunnels (p=0.007).

CONCLUSIONS

To our knowledge, this novel, semi-automated 3D-computed tomography image processing method has shown to yield highly reproducible results for the measurement of bone tunnel diameter and area. This series showed a significantly higher amount of tunnel widening observed in the allograft group at one-year follow-up.

LEVEL OF EVIDENCE

Level II, Prospective comparative study.

The clinical and radiological evaluation of the use of an allograft-prosthesis composite in the treatment of proximal femoral giant cell tumours

Giant cell tumour is the most common aggressive benign tumour of the musculoskeletal system and has a high rate of local recurrence. When it occurs in proximity to the hip, reconstruction of the joint is a challenge. Options for reconstruction after wide resection include the use of a megaprosthesis or an allograft-prosthesis composite. We performed a clinical and radiological study to evaluate the functional results of a proximal femoral allograft-prosthesis composite in the treatment of proximal femoral giant cell tumour after wide resection. This was an observational study, between 2006 and 2012, of 18 patients with a mean age of 32 years (28 to 42) and a mean follow-up of 54 months (18 to 79). We achieved excellent outcomes using Harris Hip Score in 13 patients and a good outcome in five. All allografts united. There were no complications such as infection, failure, fracture or resorption of the graft, or recurrent tumour. Resection and reconstruction of giant cell tumours with proximal femoral allograft-prosthesis composite is a better option than using a prosthesis considering preservation of bone stock and excellent restoration of function. A good result requires demanding bone banking techniques, effective measures to prevent infection and stability at the allograft-host junction.

The use of a biostatic fascia lata thigh allograft as a scaffold for autologous human culture of fibroblasts--An in vitro study

The method for covering gingival recession defects and augmenting keratinized gingiva involves the use of autogenuous connective tissue grafts obtained from palatal mucosa in combination with various techniques of flap repositioning or tunnel techniques. In the case of multiple gingival recession defects the amount of connective tissue available for grafting is insufficient. Therefore, the use of substitutes is necessary. The most widely used material in recent years has been the acellular dermal matrix allograft. The disadvantage of its application lies in the absence of cells and blood vessels, which increases incorporation time. Primary cultured human autologic fibroblasts are commonly used to optimize the healing process. The aim of this study was to examine the in vitro biocompatibility of human fascia lata allograft as a new scaffold for primary cultured human autologic fibroblasts. For that, a fibroblast culture obtained from a fragment of gingival tissue taken from the hard palate mucosa of a subject was used. After 14 days the colony cells were inoculated on a fragment of human fascia lata allograft. After a further 7 days of incubation the material was frozen, cut and prepared for histochemical examination. After two weeks of incubation, and 7 days after inoculation on a fragment of fascia lata allograft numerous accumulations of the cultured fibroblast were found that had a typical structure and produced collagen fibres. A human fascia lata allograft can be used as a scaffold for primary cultured human autologic fibroblasts. Further studies should confirm the clinical efficacy of this solution.

Renal failure due to granulomatous interstitial nephritis in native and allograft renal biopsies: experience from a tertiary care hospital

Granulomatous interstitial nephritis is a rare cause of renal failure in both native and allograft renal biopsies. Drugs and sarcoidosis are the commonest causes of granulomatous interstitial nephritis as reported in Western countries. Unlike the west, tuberculosis is the commonest cause of granulomatous interstitial nephritis in Indian subcontinent. The etiological factors, clinical course, glomerular and tubulointerstitial changes associated with granulomatous interstitial nephritis have been analyzed in the present study along with the outcome in patients with granulomatous interstitial nephritis.

Comparison of ADM and Connective Tissue Graft as the Membrane in Class II Furcation Defect Regeneration: A Randomized Clinical Trial

Background and aims. Furcally-involved teeth present unique challenges to the success of periodontal therapy and influence treatment outcomes. This study aimed to assess to compare use of ADM and connective tissue membrane in class II furcation defect regeneration.

Materials and methods. 10 patient with 2 bilaterally class II furcation defects in first and/or second maxilla or man-dibular molar without interproximal furcation involvement, were selected. Four weeks after initial phase of treatment, before and thorough the surgery pocket depth (PD), clinical attachment level to stent (CAL-S), free gingival margin to stent(FGM-S) , crestal bone to stent (Crest-S), horizontal defect depth to stent (HDD-S) and vertical defect depth to stent (VDD-S) and crestal bone to defect depth measured from stent margin. Thereafter, one side randomly treated using connective tissue and DFDBA (study group) and opposite side received ADM and DFDBA (control group). After 6 months, soft and hard tissue parameters measured again in re-entry.

Results. Both groups presented improvements after therapies (P & 0.05). No inter-group differences were seen in PD re-duction (P = 0.275), CAL gain (P = 0.156), free gingival margin (P = 0.146), crest of the bone (P = 0.248), reduction in horizontal defects depth (P = 0.139) and reduction in vertical defects depth (P = 0.149).

Conclusion. Both treatments modalities have potential of regeneration without any adverse effect on healing process. Connective tissue grafts did not have significant higher bone fill compared to that of ADM.

Biomechanical changes from long-term freezer storage and cellular reduction of tracheal scaffoldings

OBJECTIVES/HYPOTHESIS

To determine structural biomechanical changes in tracheal scaffolds resulting from cellular reduction and storage at -80(o) C.

STUDY DESIGN

Laboratory-based study.

METHODS

Forty-four rabbit tracheal segments were separated into four treatment groups: untreated (group A, control), cellular-reduced (group B), storage at -80(o) C followed by cellular reduction (group C), and cellular-reduced followed by storage at -80(o) C (group D). Tracheal segments were subjected to uniaxial tension (n = 21) or compression (n = 23) using a universal testing machine to determine sutured tensile yield load and radial compressive strengths at 50% lumen occlusion. Mean differences among groups for tension and compression were compared by analysis of variance with post-hoc Tukey-Kramer test.

RESULTS

The untreated trachea (group A) demonstrated mean yield strength of 5.93 (± 1.65) N and compressive strength of 2.10 (± 0.51) N. Following treatment/storage, the tensile yield strength was not impaired (group B = 6.79 [± 1.58] N, C = 6.21 [± 1.40] N, D = 6.26 [± 1.18]; P > 0.10 each). Following cellular reduction, there was a significant reduction in compressive strength (group B = 0.44 N [± 0.13], P < 0.0001), but no further reduction due to storage (group C = 0.39 N [± 0.10]; P = 0.97 compared to group B).

CONCLUSION

The data suggest cellular reduction leads to loss of compressive strength. Freezing at -80°C (either before, or subsequent to cellular reduction) may be a viable storage method for tracheal grafts.

Sodium tanshinone IIA sulfonate prolongs the survival of skin allografts by inhibiting inflammatory cell infiltration and T cell proliferation

Acute rejection is a major problem for allograft transplantation in the clinic. Classic immunosuppressive drug therapy is accompanied by a variety of side effects. Therefore, safe and effective immunosuppressive drugs remain in demand. In this study, the effect of sodium tanshinone IIA sulfonate (STS) on prolonging the allogeneic skin graft survival was determined using a rat skin transplantation model. Rat recipients were divided into four groups that received different treatments: physiological saline, STS, CsA, or STS+CsA. The results indicated that the administration of STS alone, CsA alone or combined STS and CsA all significantly promoted skin allograft survival as demonstrated by a longer mean survival time (MST) compared with the control group. This effect was due to the reductions in the infiltration of inflammatory cells into allograft and the percentages of CD4+ T cells and CD8+ T cells in the peripheral blood of rat recipients. The injection of STS could also downregulate the expression of RANTES, IP-10 as well as IL-2, IFN-γ and TNF-α in allograft tissue. STS markedly inhibited the proliferation of mouse spleen T lymphocytes stimulated by mitogen and alloantigen in vitro. Taken together, these results suggest that STS is a widely applicable drug with few complications that may serve as a new therapeutic alternative for allograft rejection or even other Th1 cell-dominated immune diseases.

Expression of HSPA12B in acute cardiac allograft rejection in rats

HSP70 may play a more important role in regulating antigen-specific immune response than other HSPs; however, HSPA12B production in transplanted heart remains obscure, which was identified as the newest member of the HSP70 family. In the current study, we performed a heart transplantation model in adult rats and investigated the dynamic changes of HSPA12B expression in the cardiac grafts. The cardiac grafts of allogeneic (Wistar-Lewis rat) and syngeneic (Lewis-Lewis rat) rat models were subjected to histopathological and immunohistochemical analyses for HSPA12B expression on days 0-7 after operation. We also examined the expression profiles of active caspase-3, whose changes were correlated with the expression profiles of HSPA12B. Our results demonstrated that HSPA12B protein exhibited biphasic patterns in transplanted heart. The first expression phase correlated with ischemical reperfusion injury over 2 days post-transplant. The second peak of HSPA12B expression was found only in allografts on day 5, concurrent with the expression of caspase-3. Immunohistochemical assay showed that compared with rare expression in isografts, there were significant protein expressions of HSPA12B and caspase-3 in heart allografts from day 5 to 7 post-transplant. Furthermore, double immunofluorescence staining for active caspase-3 and HSPA12B in isografts and allografts at day 5 post-transplant were analyzed and colocalization of HSPA12B/active caspase-3 was detected in allografts. In conclusion, this is the first description of HSPA12B expression in acute cardiac allograft rejection. Our results suggested that HSPA12B might play crucial roles in heart pathophysiology after transplantation.

Allograft alone versus allograft with bone marrow concentrate for the healing of the instrumented posterolateral lumbar fusion

BACKGROUND CONTEXT

Spondylodesis in the operative management of lumbar spine diseases has been the subject of numerous studies over several decades. The posterolateral fusion (PLF) with pedicle screw fixation is a commonly used procedure.

PURPOSE

To determine whether the addition of bone marrow concentrate (BMC) to allograft bone increases fusion rate after instrumented posterior lumbar fusion.

STUDY DESIGN

The study was prospective, randomized, controlled, and blinded.

METHODS

Eighty patients with degenerative disease of the lumbar spine underwent instrumented lumbar or lumbosacral PLF (22 men, 58 women; body mass index less than 35 for a good visualization of the PLF in the X-rays). In 40 cases, the PLF was done with spongious allograft chips alone (Group I, age 62.7 years in average, range 47-77 years, level of fusion 1-2). In another 40 cases, spongious allograft chips were mixed with BMC (Group II, age 58.5 years in average, range 42-80, level of fusion 1-3), including the mesenchymal stem cells (MSCs). Patients were scheduled for anteroposterior and lateral radiographs 12 and 24 months after the surgery and for computed tomography scanning 24 months after the surgery. Fusion status and the degree of mineralization of the fusion mass were evaluated separately by two radiologists blinded to patient group affiliation. The bony mass was judged as fused if there was uninterrupted bridging of well-mineralized bone between the transverse processes or sacrum, with trabeculation indicating bone maturation on least at one side of the spines.

RESULTS

In Group I at 12 months, the bone graft mass was assessed in X-rays as fused in no cases (0%) and at 24 months in four cases (10%). In Group II, 6 cases (15%) achieved fusion at 12 months and 14 cases (35%) at 24 months. The statistically significant difference between both groups was proven for complete fusion at both 12 (p=.041) and 24 months (p=.011). Computed tomography scans showed that 16 cases (40%) in Group I and 32 cases (80%) in Group II had evidence of at least unilateral continuous bridging bone between neighboring vertebrae at 24 months (p<.05).

CONCLUSIONS

We have confirmed the hypothesis that the autologous BMC together with the allograft is a better alternative for PLF than the allograft alone. The use of autologous MSCs in form of BMC in combination with allograft is an effective option to enhance the PLF healing.

Defining the biomechanical properties of the rabbit trachea

OBJECTIVES/HYPOTHESIS

Surgical advancements rely heavily on validated animal models. The New Zealand White (NZW) rabbit is a widely used model for airway research, including regenerative medicine applications. Currently, the biomechanical properties of the normal rabbit trachea are not known. Our objective was to define these properties to assist in the standardization and understanding of future airway research using this model.

STUDY DESIGN

Laboratory-based study.

METHODS

Fresh tracheas from four adult NZW rabbits were dissected into 20 segments. To examine the biomechanical properties, segments were subjected to uniaxial tension (n = 9) and compression (n = 11) testing. Yield and maximum load (tension) and force at 50% displacement (compression) were recorded, and differences between segments were examined using analysis of covariance.

RESULTS

Normative data for native rabbit trachea show mean maximum load = 6.44 newtons (N), yield load = 5.93 N, and compressive strength = 2.10 N. In addition to establishing the baseline measurements, statistically significant differences in tensile measures based on location along the trachea and diameter were identified. Proximal segments had significantly higher maximum load (P = .0029) and yield load (P = .0062) than distal segments. Association between diameter and both maximum load (P = .0139) and yield load (P = .0082) was observed.

CONCLUSIONS

The adult NZW rabbit trachea is intrinsically less able to withstand tensile and compressive forces, compared to other airway models such as sheep or cadaveric human. Establishment of normative values will enable future research into changes in tracheal biomechanical properties during regenerative medicine manipulation and processing.

Current Concepts in Restoring Acquired Cranial Defects

Restoring acquired cranial defects has been in vogue for long, and the reconstructive techniques continue to evolve. Over the decades various techniques and materials are employed in rehabilitating cranial defects. Advances in bioengineering, custom templates and Rapid prototyping technology has given greater impetus in restoring larger cranial defects. With the variety of options available it will be very crucial in deciding the best possible technique and material to rehabilitate patients with cranial defects.

Lateral meniscus allograft transplantation: clinical and anatomic outcomes after arthroscopic implantation with tibial tunnels versus open implantation without tunnels

Meniscus allograft transplantation (MAT) is used to treat patients with knee pain after total or subtotal meniscectomy. The graft can be inserted during open or arthroscopic surgery. The objectives are anatomic horn positioning and strong fixation to the bone and capsule of an appropriately sized graft.

HYPOTHESIS

Arthroscopic MAT with trans-tibial bone fixation ensures better mid-term functional outcomes and limits allograft extrusion.

PATIENTS AND METHODS

We conducted a retrospective single-centre study of 23 consecutive patients who underwent MAT between 2001 and 2010. Among them, 11 had open surgery and anchoring of the horns without tunnels and 12 had arthroscopically-assisted surgery with bony fixation of the horns through trans-tibial tunnels. The two groups were comparable at baseline. Mean follow-up was 66.1 months. Post-operative outcomes were assessed using the IKDC score and KOOS, standard radiographs of both knees, and either magnetic resonance imaging or computed arthrotomography. We measured joint space narrowing, meniscal extrusion in the sagittal and coronal planes; and the degree of cartilage coverage by the graft using an index developed for this study.

RESULTS

The overall failure rate was 17.4% (4/23, two cases each of complete and partial graft removal). Joint space narrowing increased by 28% versus the pre-operative value (P=0.009). IKDC and KOOS values were not significantly different between the two groups. Absolute meniscus extrusion was greater in the arthroscopy group (4mm vs. 3mm, P=0.03).

DISCUSSION

Osteoarthritis of the transplanted compartment is unavoidable. Open surgery is associated with less meniscal extrusion. The clinical outcomes are independent from the technique used. Other factors require investigation, including graft rehabilitation, quality peripheral suturing, and intermeniscal ligament reconstruction.

LEVEL OF EVIDENCE

IV, retrospective study.

Angiopoietin-2 inhibition prevents transplant ischemia-reperfusion injury and chronic rejection in rat cardiac allografts

Transplant ischemia-reperfusion injury (Tx-IRI) and allograft dysfunction remain as two of the major clinical challenges after heart transplantation. We investigated the role of angiopoietin-2 (Ang2) in Tx-IRI and rejection using fully MHC-mismatched rat cardiac allografts. We report that plasma levels of Ang2 were significantly enhanced in the human and rat recipients of cardiac allografts, but not in the rat recipients of syngrafts, during IRI. Ex vivo intracoronary treatment of rat cardiac allografts with anti-Ang2 antibody before 4-h cold preservation prevented microvascular dysfunction, endothelial cell (EC) adhesion molecule expression and leukocyte infiltration, myocardial injury and the development of cardiac fibrosis and allograft vasculopathy. Recipient preoperative and postoperative treatment with anti-Ang2 antibody produced otherwise similar effects without effecting microvascular dysfunction, and in additional experiments prolonged allograft survival. Recipient preoperative treatment alone failed to produce these effects. Moreover, ex vivo intracoronary treatment of allografts with recombinant Ang2 enhanced Tx-IRI and, in an add-back experiment, abolished the beneficial effect of the antibody. We demonstrate that neutralization of Ang2 prevents EC activation, leukocyte infiltration, Tx-IRI and the development of chronic rejection in rat cardiac allografts. Our results suggest that blocking Ang2 pathway is a novel, clinically feasible, T cell-independent strategy to protect cardiac allografts.

Transforming growth factor beta (TGFβ) plays a crucial role in prolonging allograft survival in an allodepletion ("pruning") skin transplant model

Adoptive cell therapies involving cell manipulation to achieve tolerance are increasingly being studied in animal models and in human trials. We have demonstrated that the specific removal of allo-stimulated dividing cells (or "pruning") promotes long-term allograft survival across a major MHC mismatch in transplant models including skin, heart and islet transplants. In this study, we examine the role of transforming growth factor beta (TGFβ), an important regulatory cytokine, on allograft survival in our allodepletion or "pruning" skin transplant model. Increased proliferation of CD4(+) T cells was observed following allo-stimulation of BALB/c spleen cells (labeled with CFSE) in the presence of the regulatory cytokines TGFβ and (interleukin-2) IL-2 in a mixed lymphocyte culture (MLC). Expression of the regulatory gene forkhead box-3 (FoxP3) was increased in both the allo-stimulated non-dividing (ND) (CFSE(high)) and dividing (D) (CFSE(low)) CD4(+) T cell populations, with the highest expression found in the D CD4(+) T cell population. Mice reconstituted with allo-stimulated ND CD4(+) T cells following TGFβ/IL-2 stimulation showed prolonged allograft survival, similar to previous data. Significantly, TGFβ/IL-2 stimulation prevented acute rejection of allografts across a major MHC mismatch in the presence of highly activated allo-stimulated D CD4(+) T cells. Blockade of TGFβ promoted rejection of allografts even following depletion of allo-stimulated D CD4(+) T cells. These studies support a crucial role for TGFβ in the survival of allografts and shows that regulatory cytokines TGFβ/IL2 can delay the rejection of allografts, even in the presence of highly activated alloreactive T cells.

Vancomycin iontophoresis of allograft bone

Objectives

The most concerning infection of allografts and operative procedures is methicillin resistant Staphylococcus aureus (MRSA) and no current iontophoresed antibiotics effectively combat this microbe. It was initially hypothesised that iontophoresis of vancomycin through bone would not be effective due to its large molecular size and lack of charge. The aim of this study was to determine whether this was a viable procedure and to find the optimum conditions for its use.

Methods

An iontophoresis cell was set up with varying concentrations of Vancomycin within the medulla of a section of sheep tibia, sealed from an external saline solution. The cell was run for varying times, Vancomycin concentrations and voltages, to gain information on optimisation of conditions for impregnating the graft. Each graft was then sectioned and dust ground from the exposed surface. The dust was serially washed to extract the Vancomycin and concentrations measured and plotted for all variables tested.

Results

Vancomycin was successfully delivered and impregnated to the graft using the iontophoresis technique. The first order fit to the whole data set gave a significant result (p = 0.0233), with a significant concentration (p = 0.02774) component. The time component was the next most significant (p = 0.0597), but did not exceed the 95% confidence level.

Conclusions

Iontophoresis is an effective method for delivering Vancomycin to allograft bone. The concentrations of the vancomycin solution affected the bone concentration, but results were highly variable. Further study should be done on the effectiveness of delivering different antibiotics using this method.

Immune tolerance of epithelium-denuded-cryopreserved tracheal allograft

OBJECTIVES

Animal and clinical studies have demonstrated the feasibility of tracheal allograft transplantation after a revascularization period in heterotopy, thus requiring immunosuppressive therapy. Given the key role of the respiratory epithelium in the immune rejection, we investigated the consequence of both epithelium denudation and cryopreservation in immune tolerance of tracheal allograft in a novel rabbit model.

METHODS

Five adult female New Zealand rabbits served as donors of tracheas that were denuded of their epithelium and then cryopreserved, and 13 males were used as recipients. Following graft wrap using a lateral thoracic fascial flap, allograft segments 20 mm in length with (n = 9) or without (n = 4) insertion of an endoluminal tube were implanted under the skin of the chest wall. The animals did not receive any immunosuppressive drugs. Sacrifices were scheduled up to 91 days. Macroscopic and microscopic examinations and detection of apoptotic cells by immunohistochemical staining (Apostain) were used to study the morphology, stiffness, viability and immune rejection of allografts.

RESULTS

There were no postoperative complications. Grafted composite allografts displayed satisfactory tubular morphology provided that an endoluminal tube was inserted. All rabbits were found to have an effective revascularization of their allograft and a mild non-specific inflammatory infiltrate with no significant lymphocyte infiltration. Cartilage rings showed early central calcification deposit, which increased over time, ensuring graft stiffness. Apoptosis events observed into the allograft cells were suggestive of minimal chronic rejection.

CONCLUSIONS

Our results demonstrated that the epithelium-denuded-cryopreserved tracheal allograft implanted in heterotopy displayed satisfactory morphology, stiffness and immune tolerance despite the absence of immunosuppressive drugs. This allograft with a fascial flap transferable to the neck should be investigated in the setting of tracheal replacement in rabbits. Similar studies need to be conducted in bigger mammals before considering clinical applications.

Clinical and radiological results of femoral head structural allograft for severe bone defects in revision TKA--a minimum 8-year follow-up

BACKGROUND

Proper treatment of bone loss is essential for the long term durability of revision TKA. However, the method of choice in managing large bone defects is still under debate. We therefore assessed the mid to long term clinical and radiographic results of revision TKA using a fresh frozen femoral head allograft and a standard condylar implant or varus-valgus constrained prosthesis with a diaphyseal-engaging stem.

METHODS

We retrospectively reviewed the records of 27 patients who had undergone revision TKA between August 1997 and March 2003 using a fresh frozen femoral head allograft and a standard condylar implant or varus-valgus constrained prosthesis with a diaphyseal-engaging stem. The median follow-up period was 107 months (range, 96-157 months).

RESULTS

Clinical evaluation revealed that the mean range of motion had increased from 71° to 113° and the mean Hospital for Special Surgery knee score had improved from 46 to 83 points. The overall tibio-femoral angle improved from varus 7.3° to valgus 6.l°. In 26 out of 27 knees, union was demonstrated at an average of seven months postoperatively, and there were no cases of collapse, disease transmission or stress fractures. In one knee, an infection recurred.

CONCLUSIONS

Our results demonstrate that femoral head allografts in treatment of severe bone defects are reliable and durable. If possible, less constrained prostheses with diaphyseal-engaging stems should be chosen for increased durability.

LEVEL OF EVIDENCE

Level IV, therapeutic study. See Guidelines for Authors for a complete description of levels of evidence.

Salvage options for peroneal tendon ruptures

Reports have demonstrated that peroneal tendon tears can be successfully treated by direct repair or debridement and tubularization, based on the extent and nature of the pathology. Irreparable peroneal tendon tears or completely unsalvageable tendons after failure of previously attempted repairs are rare, and as a result there is a lack of high-level evidence to guide the management of these complex injuries. When irreparable tears are encountered the salvage options include tenodesis, bridging of the defect using allografts or autografts, and tendon transfers. The choice of treatment strategy depends on the presence of a functioning tendon or tendons and the viability and excursion of the peroneal musculature.

Treatment of patella infera by patellar tendon lengthening and augmentation with tibialis anterior tendon allograft

Management of patella infera remains a difficult therapeutic endeavor. We report a case of a 21-year-old man, who had development of patella infera and knee flexion contracture after a patella fracture. Patella infera was treated by patellar tendon lengthening and augmentation with a tibialis anterior tendon allograft fixed with bioabsorbable cross-pins. The patient regained an anatomic patellar position and full range of motion at two years after surgery.

PET-based evaluation of allograft osteointegration

The treatment of loosened total hip replacement (THR) acetabular components may require the management of severe bone defects. Although being applied for decades, there is only limited scientific data about the osteointegration of cancellous bone allografts (CBA) and other void fillers. Monitoring of periprosthetic bone regeneration could possibly help to optimize this process thereby reducing late failure rates. The aim of this study was to show osteometabolic changes in periprosthetic CBA after THR revision with the use of sodium-[18F]-fluoride (NaF) and positron emission tomography (PET).

PATIENTS, METHODS

Twelve patients undergoing THR revision with the use of CBA were prospectively enrolled in the study. Nine patients completed all necessary examinations and were included in the evaluation. The temporal pattern of osteointegration was assessed via NaF-PET at one (PET1) and six weeks (PET2) after surgery. CBA, tantalum implants, supraacetabular regions ipsilateral and contralateral, and parasymphyseal pubic bones were delineated as volumes of interest (VOI) in postop CT scans, which were then merged with the PET data.

RESULTS

In comparison to the contralateral supraacetabular reference bone, a significant 1.5-fold increase of osteometabolic activity from PET1 to PET2 was seen in the CBA region. Also, the ipsilateral supraacetabular host bone showed a higher NaF-influx in week 6, compared to the first postoperative week. The supraacetabular site exhibited a significantly 1.8- to 2-fold higher influx and uptake than bone regions in non-operated sites. Tantalum implants had a low NaF influx at both time points investigated.

CONCLUSION

Using NaF-PET osteometabolic changes of CBA and implant-bone-interfaces can be monitored. Applying this method we demonstrated early periprosthetic temporal bone regeneration patterns in THR cup revision patients.

Secondary malignancies after allogeneic hematopoietic stem cell transplantation using reduced-intensity conditioning and outpatient conduction

BACKGROUND

Patients given allogeneic hematopoietic stem cell transplants (HSCT) may develop secondary malignant neoplasms (SMN). Several variables have been identified but there are no data about the incidence of this complication in individuals given HSCT using reduced-intensity conditioning (RIC) methods.

OBJECTIVE

Define the incidence of SMN in patients given HSCT using a RIC preparative regimen conducted on an outpatient basis.

MATERIALS AND METHODS

Patients given HSCT in two institutions between October 1998 and 2012 were analyzed. To appraise the SMN appearance, those patients dead were also regarded as censored at that moment, as well as those lost to follow up and those alive at the closing of the study. 95% Confidence intervals (CI) for the survival or failure estimate were calculated with the Greenwood's method.

RESULTS

A total of 416 allografted patients with a Karnofsky performance index of 100% were included in the study. All patients received peripheral blood stem cells allografts. The conditioning regimen was delivered as an outpatient procedure in all individuals. No patient was given radiotherapy nor antithymocyte globulin during the conditioning. Three hundred and sixty five patients (88%) were never admitted to the hospital, whereas 12% were admitted because of grade III-IV acute graft versus host disease (aGVHD), fever, or mucositis. Median survival time was 15.7 months. Survival at 6 months (95% CI): 66.4% (61.5-70.8%), at 12 months: 53.3% (48.1-58.1%), at 60 months: 30.6% (30.5-41.5%). Eight patients with a SMN were identified in the group of 416 allografted patients, SMN rates (95% CI) were: one year post graft: 1.9% (0.7-4.9%), 5 years: 3.8% (1.6-9.2%), 10 years: 6.8% (2.6-17.7%) and 13 years post-graft: 20.2% (5.5-59.2%), the cumulative probability of SMN being 6.8 at 10 years. Since the number of expected cases in the general population is 0.62, the ratio of observed to expected cases is 12.9 (P < 0.001). This figure means that the risk of developing a malignant neoplasm in allografted individuals using our method is 12.9 times higher than that in the general population. There were three non-Hodgkin's lymphomas, two M2 acute myelogenous leukemias, one hairy cell leukemia, one tongue epidermoid carcinoma, and one breast carcinoma.

CONCLUSIONS

We have found a low incidence of SMN in this group of Mexican patients allografted with the Mexican RIC method. Possible explanations for this difference are discussed, focusing on the RIC preparative regimen.

Extensor mechanism allograft in total knee arthroplasty

OBJECTIVE

To analyze the experience with allograft transplantation of the extensor mechanism in total knee arthroplasty and compare results with the international experience.

METHODS

We retrospectively evaluated three cases of extensor mechanism allograft after total knee arthroplasty performed in our hospital with the aid of one of the few tissue banks in Brazil and attempt to establish whether our experiences were similar to others reported in the world literature regarding patient indication, techniques, and outcomes.

RESULTS

Two cases went well with the adopted procedure, and one case showed bad results and progressed to amputation. As shown in the literature, the adequate tension of the graft, appropriate tibial fixation and especially the adequate patient selection are the better predictors of good outcomes. Previous chronic infection can be an unfavorable predictor.

CONCLUSION

This surgical procedure has precise indication, albeit uncommon, either because of the rarity of the problem or because of the low availability of allografts, due to the scarcity of tissue banks in Brazil. Level of Evidence IV, Case Series.

Anterior cruciate ligament reconstruction best practice: A review of graft choice

There is much literature about differing grafts used in anterior cruciate ligament (ACL) reconstruction. Much of this is of poor quality and of a low evidence base. We review and summarise the literature looking at the four main classes of grafts used in ACL reconstruction; bone-patella tendon-bone, hamstrings, allograft and synthetic grafts. Each graft has the evidence for its use reviewed and then compared, where possible, to the others. We conclude that although there is no clear “best” graft, there are clear differences between the differing graft choices. Surgeon’s need to be aware of the evidence behind these differences, in order to have appropriate discussions with their patients, so as to come to an informed choice of graft type to best suit each individual patient and their requirements.

Socket preservation using demineralized freezed dried bone allograft with and without plasma rich in growth factor: A canine study

BACKGROUND

The accelerating effect of plasma rich in growth factors (PRGFs) in the healing of extraction sockets has been demonstrated by some studies. The aim of the present study was to histologically and histomorphometrically evaluate whether bone formation would increase by the combined use of PRGF and demineralized freeze-dried bone allograft (DFDBA).

MATERIALS AND METHODS

In four female dogs, the distal root of the second, third and fourth lower premolars were extracted bilaterally and the mesial roots were preserved. The extraction sockets were randomly divided into DFDBA + PRGF, DFDBA + saline or control groups. Two dogs were sacrificed after 2 weeks and two dogs were sacrificed after 6 weeks. The extraction sockets were evaluated from both histological and histomorphometrical aspects. The data were analyzed by Mann-Whitney followed by Kruskal-Wallis tests using the Statistical Package for the Social Sciences version 20 (SPSS Inc., Chicago, IL, USA). Significant levels were set at 0.05.

RESULTS

The least decrease in socket height was observed in the DFDBA + PRGF group (0.73 ± 0.42 mm). The least decrease in the coronal portion was observed in the DFDBA + PRGF group (1.38 ± 1.35 mm²). The least decrease in the middle surface was observed in the DFDBA group (0.61 ± 0.80 mm²). The least decrease in the apical portion was observed in the DFDBA group (0.34 ± 0.39 mm²).

CONCLUSION

The present study showed better socket preservation subsequent to the application of DFDBA and PRGF combination in comparison with the two other groups. However, the difference was not statistically significant.

Tissue-engineered tracheal reconstruction using chondrocyte seeded on a porcine cartilage-derived substance scaffold

OBJECTIVES

Tracheal reconstruction with tissue-engineering technique has come into the limelight in the realm of head and neck surgery. We intended to evaluate the plausibility of allogenic chondrocytes cultured with porcine cartilage-derived substance (PCS) scaffold for partial tracheal defect reconstruction.

METHODS

Powder made from crushed and decellularized porcine articular cartilage was formed as 5 mm × 12 mm (height × diameter) scaffold. Chondrocytes from rabbit articular cartilage were expanded and cultured with PCS scaffold. After 7 weeks culture, the scaffolds were implanted on a 5 mm × 10 mm artificial tracheal defect in six rabbits. Two, four and eight weeks postoperatively, the sites were evaluated endoscopically, radiologically, histologically and functionally.

RESULTS

None of the six rabbits showed any sign of respiratory distress. Endoscopic examination did not show any collapse or blockage of the reconstructed trachea and the defects were completely covered with regenerated respiratory epithelium. Computed tomography showed good luminal contour of trachea. Postoperative histologic data showed that the implanted chondrocyte successfully formed neo-cartilage with minimal inflammatory response and granulation tissue. Ciliary beat frequency of regenerated epithelium was similar to those of normal adjacent mucosa.

CONCLUSIONS

The shape and function of reconstructed trachea using allogenic chondrocytes cultured with PCS scaffold was restored successfully without any graft rejection.

Utilizing reamer irrigator aspirator (RIA) autograft for opening wedge high tibial osteotomy: A new surgical technique and report of three cases

INTRODUCTION

The lateral closing wedge high tibial osteotomy (HTO) was popularized by Coventry in the 1960s. In the 1990s the medial opening wedge osteotomy gained popularity because it could achieve greater valgus correction and it did not require dissociation of the fibula from the tibia, an important consideration when treating varus knees with lateral and posterolateral ligament deficiencies (Noyes’ double-varus and triple-varus knees). However, it has the disadvantage of requiring bone graft to fill bony defects. Recently, the reamer-irrigator-aspirator (RIA; Synthes, Paoli, PA) system was developed, and as a result of this procedure, a large amount of usable autogenous bone graft can be collected safely for use. To our knowledge, there is no published series combining opening wedge HTO with the use of RIA obtained autogenous bone graft.

PRESENTATION OF CASE

We present a novel technique in which a series of three patients underwent opening wedge HTO using ipsilateral, retrograde femur RIA graft to fill the bone defect. All patients had satisfactory clinical and radiologic outcomes following the new technique at latest follow up.

DISCUSSION

Opening wedge high tibial osteotomy is a well-documented and accepted orthopedic procedure, however, has the disadvantage of requiring varying amounts of bone graft. Traditionally, iliac crest or tricortical allograft have been the grafting modalities of choice, however both have inherent drawbacks to their use. In our series, the use of RIA autograft is a safe and reliable harvest technique for high tibial osteotomy, providing abundant and quality autogenous bone graft.

CONCLUSION

All three of our patients achieved radiographic union with high clinical patient satisfaction without any major complications. We feel this novel technique is a safe and acceptable operative solution grafting opening wedge osteotomies about the knee.

Allograft reconstruction for digital nerve loss

PURPOSE

To investigate the outcomes of digital nerve repairs using processed nerve allograft for defects measuring 30 mm or less.

METHODS

Seventeen patients with 21 digital nerve lacerations in the hand underwent reconstruction with processed nerve allograft. Outcome data for 14 patients with 18 digital nerve lacerations were available for analysis. Postoperative outcome data were recorded at a minimum of 12 months and an average of 15 months. The average nerve gap measured 11 mm (range, 5-30 mm). Outcome measures included postoperative sensory examination as assessed by Semmes-Weinstein monofilaments and static and moving 2-point discrimination. Pain was graded using a visual analog scale throughout the recovery period. In addition, patients completed the Quick Disabilities of the Arm, Shoulder, and Hand survey before and after surgery.

RESULTS

Using Taras outcome criteria, 7 of 18 (39%) digits had excellent results, 8 of 18 (44%) had good results, 3 of 18 (17%) digits had fair results, and none had poor results. At final follow-up, Semmes-Weinstein monofilament testing results ranged from 0.08 g to 279 g. Quick Disabilities of the Arm, Shoulder, and Hand scores recorded at the patient's first postoperative visit averaged 45 (range, 2-80), and final scores averaged 26 (range, 2-43). There were no signs of infection, extrusion, or graft reaction.

CONCLUSIONS

The data suggest that processed nerve allograft provides a safe and effective alternative for the reconstruction of peripheral digital nerve deficits measuring up to 30 mm.

Diagnostic usefulness of white blood cell and absolute neutrophil count for postoperative infection after anterior cervical discectomy and fusion using allograft and demineralized bone matrix

Study Design

Prospective study.

Purpose

We investigated normative temporal levels of white blood cell (WBC) and absolute neutrophil count (ANC) in uncomplicated anterior cervical discectomy and fusion (ACDF) using allograft and demineralized bone matrix (DBM).

Overview of Literature

No study has investigated the diagnostic usefulness of WBC and ANC for postoperative infection following ACDF using allograft and DBM.

Methods

Blood samples of 85 patients, who underwent one or two-level ACDF, were obtained and evaluated before surgery and on the first, third, fifth, seventh, fourteenth, thirtieth, and ninetieth postoperative days. No infection was found in all patients for at least one year follow-up period.

Results

Mean WBC and ANC values increased significantly and reached peak levels on the first postoperative day. The peaked levels rapidly decreased but still remained elevated above the preoperative levels on the third postoperative day. The levels returned close to the preoperative levels on the fifth postoperative day. The mean WBC and ANC values did not get out of their normal reference ranges throughout the follow-up periods. One-level and two-level ACDF exhibited a similar course of postoperative changes in WBC and ANC values and no significant difference in mean levels of WBC and ANC throughout the follow-up periods.

Conclusions

Uncomplicated ACDF using allograft and DBM showed normal values of WBC and ANC during the early postoperative period. Therefore, significant abnormal values of WBC and ANC at an early postoperative period suggest the possibility of the development of acute postoperative infection after ACDF using allograft and DBM.

Prevalence of Allograft Contamination During Intraoperative Processing for Spinal Deformity Correction Surgery

STUDY DESIGN

Prospective study.

OBJECTIVES

To prospectively evaluate bone allografts during spinal fusion surgery for 1) the rate of contamination as a result of perioperative preparation, and 2) the types of bacterial organisms that may be transmitted through the contaminated bone allograft.

SUMMARY OF BACKGROUND DATA

Bone allografts are routinely used to enhance spinal arthrodesis procedures. Ready availability and lack of donor site morbidity make them valuable alternatives to iliac crest bone grafts. Reports of disease transmission of such organisms as hepatitis C, the human immunodeficiency virus, and a variety of bacterial pathogens through allograft bone implants raise concerns for patient and practitioner safety.

METHODS

Our study population consisted of 50 consecutive (20 male and 30 female) patients (mean age at surgery, 15 years; range, 3-51 years) undergoing spinal deformity correction from May 2010 through October 2010, by 1 surgeon at 1 institution. The mean operative time was 297 minutes (range, 81-444 minutes), and the most commonly fused spinal levels were T5 to L4. During the procedure, the researchers prospectively obtained intraoperative microbial culture swabs from a container with freeze-dried allograft and from an empty identical control container. Aerobic and anaerobic bacterial culture growth was assessed for 7 days postoperatively. Each patient was observed for 6 weeks after surgery to ascertain any evidence of surgical-site infection.

RESULTS

Microbial cultures showed bacterial growth in 4 cases: 1 allograft specimen (day 4, very light Staphylococcus aureus) and 3 control specimens (day 3, very light Enterococcus; day 4, very light S aureus; and day 6, Propionibacterium acnes). No patient showed signs of infection in the perioperative or 6-week postoperative period.

CONCLUSIONS

Intraoperative allograft preparation is not a major source of bone allograft contamination during spinal surgery.

Risk of virus transmission through femoral head allografts: A Belgian appraisal

BACKGROUND

To evaluate the incidence and the risk of transmitting a virus through a bone allograft from a living donor.

MATERIAL AND METHODS

A total 7032 femoral heads have been collected from 24 Belgian institutions. The tissue along with the screening blood tests were systematically sent to the bank. Serological screening included: for HIV, a HIV1-2 antibody test; for HBV, a HBS antigen and HBS and Hbcore antibodies; for HCV, a HCV antibody test. Syphilis was also screened with a non-specific and a specific assays. HTLV1-2 screening was recommended but not obligatory.

RESULTS

From the 7032 femoral heads, 1066 (15.2%) implants were definitively excluded. Hundred forty-six femoral heads, representing 2.1% of all grafts and 13.9% of the excluded ones, were discarded for positive serological testing associated with a risk of disease transmission. There were 2 donors who tested positive for HTLV1-2. The prevalence of HIV in the femoral head donor population was six times lower than in the general one. The prevalence of hepatitis B and C was similar but far higher than HIV. The risk was computed to be 0.54 out of 1 × 10(5) for HIV and HCV without quarantine or tissue processing. For HBV, the risk was 0.77 out of 1 × 10(5).

CONCLUSION

Current standards of tissue banking incorporated safety and quality as their main features. This policy is now regulated at the European level. With a multi-step screening-policy, stringent donor selection guidelines, the risk of viral transmission trough a tissue is minimized.