Induced membrane technique using enriched bone grafts for treatment of posttraumatic segmental long bone defects.

BACKGROUND: Reconstruction of posttraumatic bone defects represents a difficult challenge. The induced membrane technique is an effective two-stage procedure for bone defect reconstruction. To overcome the problems of autologous bone grafting, different graft substitutes have been investigated. The aim of the present study is to evaluate our clinical experience in reconstruction of critical posttraumatic bone defects using an induced membrane technique based on a combination of autologous graft and allograft (cancellous bone) enriched with platelet-rich plasma (PRP) and bone marrow concentrate aspirate (BMCA). MATERIALS AND METHODS: Between 2009 and 2014, we reconstructed 18 posttraumatic bone defects in 16 patients. Their average length was 6.4 cm (range 1.6-13.2 cm). The defect location was the femur in nine cases (50%), the tibia in eight (44%) cases, and the humerus in one (6%) case. In all cases, we used a combination of autologous and cancellous allograft graft enriched with PRP and BMCA. Bone fixation was achieved using intramedullary nailing in 2 cases (11%), plating in 15 cases (66%), and external fixation in 1 case (6%). RESULTS: Both clinical and radiographic union were achieved in 13 (72%) cases (13 patients). Five (28%) cases (four patients) developed nonunion. Nonunion was observed in two of eight (25%) tibial defects and in three (33%) of nine femoral defects (ns). Three of 4 (75%) double defects had delayed union, whereas 2 of 14 (14%) single defects did not heal (p = 0.016). The average length of the 13 defects that united was 6 cm (range 1.6-11.8 cm), while the length of the 5 defects that did not unite was 10.3 cm (range 6-13.2 cm) (p = 0.009). CONCLUSIONS: In this series using an induced membrane technique based on a combination of autograft and allograft enriched with BMCA and PRP, the healing rate was lower than in other series where autologous bone graft alone was employed. Nonunion was more frequent in longer and double defects. Further research aimed at developing effective alternative options to autogenous cancellous bone graft is desirable. LEVEL OF EVIDENCE: III.

Cryotherapy efficacy and safety as local therapy in surgical treatment of musculoskeletal tumours. A retrospective case series of 143 patients.

Cryotherapy, also called Cryoablation (CA), is a technique that provides a local treatment to various pathological conditions. In Musculoskeletal tumours management, Cryoablation is well accepted and validated as a treatment in palliative cures for metastatic patients. Recently, CA has been proposed also as an alternative to radiofrequency ablation in osteoid osteoma and other benign tumour treatment with promising results. Cryotherapy with argon ice-balls as local adjuvant in open surgery is a tool that can provide enlargement of surgical margins if used properly. There is still not enough evidence supporting use of cryotherapy as local adjuvant in Musculoskeletal open surgery as the series cited above are very small and there is no comparative RCT between local adjuvant therapies including CA. One-hundred-and-eighty-three patients were treated with Cryoablation from 2000 and 2018 in the Musculoskeletal Tumours Surgery Unit of Careggi (Florence) and the University 2nd Clinic of Pisa. In our study group, 38 patients (26.6%) were affected by bone metastasis, 16 patients (11.1%) by aneurismal bone cysts or angiomas, 22 patients (15.4%) by low-grade malignant musculoskeletal tumours, 2 patients (1,4%) by fibromatosis, 63 patients (44.1%) by benign musculoskeletal tumours (principally Giant Cell Tumours-GCT) and 2 patients (1.4%) by Osteosarcomas. In 125 cases (87.4%), CA has been used as an adjuvant therapy, in 12 cases (8.4%) as a percutaneous ablation therapy and in 6 cases (4.2%) as adjuvant to remove tumoral lesions 'en bloc' or as a 'poor technique' for its sterilizing effect on previously resected bones. Mean follow-up was 10 years. Twenty-three patients (16%) were classified as Alive with Disease (AWD) due to local recurrence or tumour progression (14 metastases, 5 low-grade malignant bone tumours, 4 Giant Cell Tumours). Eight patients died due to the disease (6 metastases, 2 osteosarcomas), while 1 died from leukaemia. One-hundred-and-eleven patients (78%) were classified as Continues Disease Free (CDF). All patients reported decrease in pain-related symptoms after surgery and all surgeons reported better control of blood loss. Three cases (2%) of local skin necrosis or wound dehiscence were reported. No local recurrences were reported after fibromatosis ablation. Our results confirm that CA could be considered as a safe and effective technique to treat various conditions as adjuvant and palliative therapy. In particular, in open surgery, cryotherapy as an adjuvant treatment could lead to very low rates of recurrence in locally aggressive tumours like Giant Cell Tumours. These results could be generalized but a better understanding about indications and outcomes can be reached studying CA in specific populations with comparation to other adjuvant techniques.

Complications and survival of megaprostheses after resection of bone metastases.

Treatment of bone metastases is often palliative, aiming at pain control and stabilization or prevention of pathological fractures. However, a complete resection with healing purposes can be performed in selected cases. The aim of our work was to evaluate the survival of megaprostheses used for reconstruction after bone metastases. Between January 2001 and March 2015, we implanted 169 Megasystem-C® (Waldemar LINK® GmbH & Co. KG, Hamburg, Germany) after bone metastasis resection. Patients, 95 females and 74 males, were operated at an average age of 61 (12-87) years for proximal femoral resection in 135 (79.9%) cases, distal femur in 24 (14.2%), proximal tibia in 6 (3.6%), total femur in 3 (1.8%) and intercalary femur in 1 (0.6%). Mostly, breast cancer metastases (30.8%), kidney (17.8%) and lung (14.2%) were treated. At an average follow-up of 21 (1-150) months, we found a 99.4% overall limb salvage and a 96.1% overall survival rate at 1 year, 92.8% at 2 years, and 86.8% at 5 and 10 years. We found 9 (5.3%) mobilization cases of the proximal femoral implant, 3 needed surgical reduction; 2 (1.2%) cases of aseptic loosening of the prosthetic stem; 2 (1.2%) periprotetic infection cases, one requiring a 2-stage revision. Few literature studies have evaluated the survival of megaprosthetic implant in the treatment of bone metastases. Our data show how in this specific context the rate of complications is significantly lower than expected in general orthopedic orthopedic surgery. The use of modular prostheses is a valid reconstructive strategy after bone metastasis resection in selected patients. The rate of short-term complications is exceptionally low; further studies will have to confirm this in the longer term.

OSTEOARTICULAR ALLOGRAFTS IN PAEDIATRIC BONE TUMOR RECONSTRUCTION OF THE KNEE.

Osteoarticular allografts represent a reconstructive option after bone tumor resection around the knee in growing children. The major advantage is the chance to preserve the growth plate of the remaining bone, but the disadvantage is the high failure rate eventually requiring definitive prosthetic replacement at skeletal maturity. We retrospectively reviewed 22 patients who underwent osteoarticular allograft reconstructions of the distal femur (16) or proximal tibia (6). There were 12 females and 10 males with an average age at surgery of 11 years (7-15). The diagnosis was osteosarcoma in 19 cases and Ewing sarcoma in 3. All patients underwent pre- and post-operative chemotherapy. At an average follow-up of 103 months (12-167), 18 patients (82%) were alive and 4 had died (18%). We observed 10 allograft failures requiring prosthetic replacement, 6 in distal femur and 4 in proximal tibia reconstructions. At last follow-up 8 allografts (36%) were still in place. Overall allograft survival was 79.6% at five and 45.8% at ten years. In distal femur, allograft survival was 86.2% at five and 59.1% at ten years. In proximal tibia, allograft survival was 62.5% at 5 years and 31.2% at 67 months. Average limb shortening was 3 cm (0- 5) in 8 patients with the allograft still in situ and 2 cm (0-4) in 10 patients after prosthetic replacement. Average MSTS functional score of the whole series was 25 (83.7%). The MSTS score of patients after revision with prosthetic replacement was 24 (80%) while patients who still had the allograft retained had an average MSTS scores of 26.8 (89.3%). In conclusion, osteoarticular allograft reconstruction of the knee after bone tumor resection in pediatric age can be considered a temporary solution with the aim to limit limb length discrepancy before definitive prosthetic replacement after skeletal maturity.

GPT-based chatbot tools are still unreliable in the management of prosthetic joint infections.

BACKGROUND: Artificial intelligence chatbot tools responses might discern patterns and correlations that may elude human observation, leading to more accurate and timely interventions. However, their reliability to answer healthcare-related questions is still debated. This study aimed to assess the performance of the three versions of GPT-based chatbots about prosthetic joint infections (PJI). METHODS: Thirty questions concerning the diagnosis and treatment of hip and knee PJIs, stratified by a priori established difficulty, were generated by a team of experts, and administered to ChatGPT 3.5, BingChat, and ChatGPT 4.0. Responses were rated by three orthopedic surgeons and two infectious diseases physicians using a five-point Likert-like scale with numerical values to quantify the quality of responses. Inter-rater reliability was assessed by interclass correlation statistics. RESULTS: Responses averaged "good-to-very good" for all chatbots examined, both in diagnosis and treatment, with no significant differences according to the difficulty of the questions. However, BingChat ratings were significantly lower in the treatment setting (p = 0.025), particularly in terms of accuracy (p = 0.02) and completeness (p = 0.004). Agreement in ratings among examiners appeared to be very poor. CONCLUSIONS: On average, the quality of responses is rated positively by experts, but with ratings that frequently may vary widely. This currently suggests that AI chatbot tools are still unreliable in the management of PJI.

Scaffolds combined with stem cells and growth factors in healing of pseudotumoral lesions of bone.

Reconstructions of large lesions or defects often require a bone graft or a bone substitute to promote healing. In common practice the reconstruction of a bone defect is dependent on the site and size of the lesion: in long bones intercalary defects may be managed with Ilizarov technique of bone transport and distraction osteogenesis or the use of a free or pedicled vascularized bone graft, or with Masquelet technique. For cavitary defects the available surgical options include autograft, allograft or xenograft or the use of synthetic scaffolds to promote bone regeneration. In order to promote a faster bone healing tissue engineering proposed the application of enriched graft to fill bone defects. The employment of enriched bone graft has been our choice in the last years to fill contained defects following curettage of a pseudotumoral lesion of bone. We report our clinical experience in terms of safety and success of these procedures at a long-term follow up.

Intercalary reconstruction of femur after tumour resection: is a vascularized fibular autograft plus allograft a long-lasting solution?

Aims: After intercalary resection of a bone tumour from the femur, reconstruction with a vascularized fibular graft (VFG) and massive allograft is considered a reliable method of treatment. However, little is known about the long-term outcome of this procedure. The aims of this study were to determine whether the morbidity of this procedure was comparable to that of other reconstructive techniques, if it was possible to achieve a satisfactory functional result, and whether biological reconstruction with a VFG and massive allograft could achieve a durable, long-lasting reconstruction. Patients and Methods: A total of 23 patients with a mean age of 16 years (five to 40) who had undergone resection of an intercalary bone tumour of the femur and reconstruction with a VFG and allograft were reviewed clinically and radiologically. The mean follow-up was 141 months (24 to 313). The mean length of the fibular graft was 18 cm (12 to 29). Full weight-bearing without a brace was allowed after a mean of 13 months (seven to 26). Results: At final follow-up, the mean Musculoskeletal Tumor Society Score of 22 evaluable patients was 94% (73 to 100). Eight major complications, five fractures (21.7%), and three nonunions (13%) were seen in seven patients (30.4%). Revision-free survival was 72.3% at five, ten, and 15 years, with fracture and nonunion needing surgery as failure endpoints. Overall survival, with removal of allograft or amputation as failure endpoints, was 94.4% at five, ten, and 15 years. Discussion: There were no complications needing surgical revision after five years had elapsed from surgery, suggesting that the mechanical strength of the implant improves with time, thereby decreasing the risk of complications. In young patients with an intercalary bone tumour of the femur, combining a VFG and massive allograft may result in a reconstruction that lasts a lifetime. Cite this article: Bone Joint J 2018;100-B:378-86.

Soft tissue sarcomas of the popliteal fossa: outcome and risk factors.

BACKGROUND: Limb salvage surgery of popliteal soft tissue sarcomas may be hampered due to the incomplete anatomical containment of this region and the vicinity of neurovascular structures. The scope of this study was to determine outcome and to define risk factors. PATIENTS AND METHODS: 27 patients (53.3+/-15.8 y; 16/27 male) with popliteal soft tissue sarcomas were assessed. Mean follow-up was 40.9+/-33.8 months (48.5+/-36.7 months in surviving patients). 9/27 patients were included after prior treatment elsewhere (5 after intralesional resections and 4 local recurrences). The lesions were staged IB in 8/27 patients, IIB in 17/27 and III in 2/27. Immediate amputations were performed in 7/27 patients. 15/27 patients were subjected to radiation therapy (preoperative in 6/15 cases), 8/27 patients received chemotherapy (5/8 preoperatively). RESULTS: Overall survival and disease-free survival at 5 y was 63.0% and 59.5%. Local recurrence occurred in 2 patients. 8/27 patients developed metastatic disease after 28.9+/-9.8 months. Survival (p=0.397) and disease-free survival (p=0.113) did not differ in patients after amputations vs limb salvage. Application of radiation therapy was associated with a better survival (p=0.003). Complications related to the surgical intervention were recorded in 2/27 patients, complications related to radiation therapy occurred in 6/15 patients. DISCUSSION: Despite being extra-compartmental, popliteal sarcomas can be treated with a high rate of limb salvage while equal safety compared to amputations is maintained. Irradiation improved survival in our patient population. In cases with involvement of neurovascular structures, preoperative down-staging with radio or chemo-therapy may prevent amputation.

Osteoid osteoma of the femur with a double nidus: a case report.

Osteoid osteoma is a common benign lesion, that occurs in children and young adults. The authors report the observation of a multifocal lesion which is infrequently reported in the literature. S.A., a 10-year-old female came to our observation complaining of spontaneous pain in her right hip and cruralgia radiating to the homolateral knee over the last 6 months; the symptoms, which increased during the night, were relieved by treatment with NSAIDS. Clinical examination and imaging studies confirmed a diagnosis of osteoid osteoma with a double nidus; the lesion was treated by CT-guided thermo-ablation with radiofrequency under general anaesthesia. Complete regression of symptoms was observed at 2-year follow-up.

Retrieved human allografts : a clinicopathological study.

BACKGROUND: We studied seventy-three massive preserved human allografts, retrieved from two to 156 months after implantation, to provide insight into the mechanisms of their repair. METHODS: The specimens were studied with radiographic and histological techniques that permitted time-related quantitative analysis of the reparative mechanisms of union, cortical repair, soft-tissue attachment, fracture, and characteristics of the allograft-cement interface and the articular cartilage. RESULTS: Union at cortical-cortical junctions occurred slowly (approximately twelve months) by host-derived external callus that bridged the junction and filled the gap between abutting cortices. The bone in the gap did not undergo stress-oriented remodeling even after many years, and, when the union was intentionally disrupted, failure occurred at the cement line that marked the allograft-host junction. Repair of the necrotic graft matrix was both external and internal. External repair consisted of the apposition of a thin seam of host bone on the outer surface of the graft, coating about 40% of the surface at one year and 80% at two years. Internal repair was confined to the ends and the periphery of the cortices and penetrated so slowly that only 15% to 20% of the graft was repaired by five years, after which deeper repair seldom occurred. Graft fractures in specimens retrieved soon after fracture showed only necrotic bone adjacent to the fracture site, whereas those retrieved after fracture-healing showed a marked increase in internal repair of the bone about the fracture site. When bone cement had been used to fix a prosthesis, there was no evidence of bone resorption or loosening of the device. The osteoarticular specimens showed no survival of chondrocytes in the articular cartilage. However, the architecture of the acellular cartilage was well preserved after two to three years and occasionally after as many as five years. Late degenerative changes in the articular cartilage coincided with subchondral revascularization and fragmentation, and the articulating surfaces became covered by a pannus of fibrovascular reparative tissue. Degenerative changes in articular cartilage occurred earlier and were more advanced in specimens retrieved from patients with an unstable joint than in those retrieved from patients with a stable joint. CONCLUSIONS: Repair of massive human allografts is an indolent process that follows a fairly predictable course during the first few years and is influenced by other biological activities, such as fracture repair, supplementary autografting, and tumor recurrence.

Unicameral and aneurysmal bone cysts.

Unicameral and aneurysmal bone cysts are considered tumorlike conditions of unclear origin. The diagnosis of unicameral bone cysts is almost always based on the radiographic appearance, whereas aneurysmal bone cyst imaging may sometimes mimic a sarcomatous lesion. Several pathogenetic hypotheses [correction of hypothesis] reported in literature have been described. Classifications have been proposed to detect the activity of the cysts and to predict the prognostic behavior. The results observed with different options of treatment have been discussed.

Bizarre parosteal osteochondromatous proliferation (Nora's lesion). Description of six cases and a review of the literature.

The authors report their experience with 6 cases of bizarre parosteal osteochondromatous proliferation (BPOP) observed in 4 patients in its typical site (distal ends of the limbs), and in 2 patients where it was instead atypically localized in the humerus and femur. The histories of the patients revealed that 50% reported previous trauma in the site of lesion. Five patients were submitted to surgical exeresis, while the remaining patient refused to undergo any type of treatment because he was asymptomatic. At a mean follow-up of 36 months 1 patient presented with recurrence (20%). BPOP is a rare pseudotumorous lesion with typical radiographic and histopathologic findings similar to to those of other benign and malignant tumor forms. A review of the small amount of literature in existence is used to analyze the elements that may lead to accurate differential diagnosis.

Rotationplasty in segmental resections of the femur.

The authors report 26 cases of high-grade malignant tumors of the distal femur (23 osteosarcomas, 3 Ewing's tumors) submitted to rotation-plasty. The five-years actuarial survival rate (in the 23 cases of osteosarcoma) was 69% and there was no incidence of local recurrence. The following complications were observed: wound dehiscence (6 cases), arterial thrombosis (in 2 patients submitted to resection and vascular termino-terminal suturing), paralysis of the sciatic nerve (2 cases), delay in consolidation (2 cases), traumatic fracture of the neo-femur (3 cases). All of the complications were resolved favorably, 5 of these requiring surgical treatment (33%). Satisfactory functional results were obtained in all of the cases, except in one patient who had limitation of the ankle joint subsequent to vascular compartmental syndrome. On the basis of the oncological, functional and biomechanical results reported in this study and in the literature, the authors discuss current indications for rotation-plasty.

A histomorphologic study of explants of massive allografts: preliminary results.

The authors report their experience in the histologic study of massive allografts, explanted as a result of oncological, mechanical or biological complications. The study was conducted according to the method of inclusion in methyl methacrylate that does not involve decalcification. A description is provided of all of the phases of fusion between graft and host bone in the site of the osteotomies, as well as distribution of revascularization and rehabilitation of the graft, attachment of the soft tissues, and finally, modifications in the joint cartilage of the osteoarticular grafts. The allograft must be considered to be osteoconductive, and is only weakly osteoinductive. Incorporation of the graft is a slow and incomplete process that follows sequential phases. The Volkmann's canals in the osteotomies constitute the preferred paths for rehabilitation of the graft that is on the order of millimeters on the surface and centimeters in the site of the osteotomies. The greatest modifications have been observed in the joint cartilage. The cartilaginous cells appear to be vital only from a morphological point of view.

Giant cell tumours of the small bones of the hands and feet: long-term results of 30 patients and a systematic literature review.

Giant cell tumours (GCTs) of the small bones of the hands and feet are rare. Small case series have been published but there is no consensus about ideal treatment. We performed a systematic review, initially screening 775 titles, and included 12 papers comprising 91 patients with GCT of the small bones of the hands and feet. The rate of recurrence across these publications was found to be 72% (18 of 25) in those treated with isolated curettage, 13% (2 of 15) in those treated with curettage plus adjuvants, 15% (6 of 41) in those treated by resection and 10% (1 of 10) in those treated by amputation. We then retrospectively analysed 30 patients treated for GCT of the small bones of the hands and feet between 1987 and 2010 in five specialised centres. The primary treatment was curettage in six, curettage with adjuvants (phenol or liquid nitrogen with or without polymethylmethacrylate (PMMA)) in 18 and resection in six. We evaluated the rate of complications and recurrence as well as the factors that influenced their functional outcome. At a mean follow-up of 7.9 years (2 to 26) the rate of recurrence was 50% (n = 3) in those patients treated with isolated curettage, 22% (n = 4) in those treated with curettage plus adjuvants and 17% (n = 1) in those treated with resection (p = 0.404). The only complication was pain in one patient, which resolved after surgical removal of remnants of PMMA. We could not identify any individual factors associated with a higher rate of complications or recurrence. The mean post-operative Musculoskeletal Tumor Society scores were slightly higher after intra-lesional treatment including isolated curettage and curettage plus adjuvants (29 (20 to 30)) compared with resection (25 (15 to 30)) (p = 0.091). Repeated curettage with adjuvants eventually resulted in the cure for all patients and is therefore a reasonable treatment for both primary and recurrent GCT of the small bones of the hands and feet.

The use of osteo-articular allografts for reconstruction after resection of the distal radius for tumour.

Several techniques have been described to reconstruct a mobile wrist joint after resection of the distal radius for tumour. We reviewed our experience of using an osteo-articular allograft to do this in 17 patients with a mean follow-up of 58.9 months (28 to 119). The mean range of movement at the wrist was 56° flexion, 58° extension, 84° supination and 80° pronation. The mean ISOLS-MSTS score was 86% (63% to 97%) and the mean patient-rated wrist evaluation score was 16.5 (3 to 34). There was no local recurrence or distant metastases. The procedure failed in one patient with a fracture of the graft and an arthrodesis was finally required. Union was achieved at the host-graft interface in all except two cases. No patient reported more than modest non-disabling pain and six reported no pain at all. Radiographs showed early degenerative changes at the radiocarpal joint in every patient. A functional pain-free wrist can be restored with an osteo-articular allograft after resection of the distal radius for bone tumour, thereby avoiding the donor site morbidity associated with an autograft. These results may deteriorate with time.

Biological reconstruction after resection of bone tumours around the knee: long-term follow-up.

We reviewed 25 patients who had undergone resection of a primary bone sarcoma which extended to within 5 cm of the knee with reconstruction by a combination of a free vascularised fibular graft and a massive allograft bone shell. The distal femur was affected in four patients and the proximal tibia in 21. Their mean age at the time of operation was 19.7 years (5 to 52) and the mean follow-up period 140 months (28 to 213). Three vascularised transfers failed. The mean time to union of the fibula was 5.6 months (3 to 10) and of the allograft 19.6 months (10 to 34). Full weight-bearing was allowed at a mean of 21.4 months (14 to 36). The mean functional score at final follow-up was 27.4 (18 to 30) using a modified 30-point Musculoskeletal Tumour Society rating system. The overall limb-salvage rate was 88%. The results of our study suggest that the combined use of a vascularised fibular graft and allograft is of value as a limb-salvage procedure for intercalary reconstruction after resection of bone tumours around the knee, especially in skeletally immature patients.

Limb salvage surgery in combination with brachytherapy and external beam radiation for high-grade soft tissue sarcomas.

While combined treatment of high-grade soft tissue sarcoma with resection and radiotherapy has become an accepted standard, outlines of treatment algorithms remain a matter of debate. Our institutional practice foresees wide surgical resection with adjuvant brachytherapy and external beam radiation. It was the purpose of this study to determine long-term outcome, prognostic factors for local and systemic recurrence and morbidity in patients with high-grade soft tissue sarcomas of the extremities, who were subjected to this regimen. One hundred and twelve patients met the inclusion criteria (56 male, 56 female; median age, 50 years). Median follow-up was 75 months (min. 11 months). Overall survival rate was 77.5% and 71.1% at 5 and 7 years, respectively. Disease-free survival rate was 63.3% and 58.4% at 5 and 10 years, respectively. Local control was achieved in 91.5% and 87.0% at 5 and 10 years, respectively. Wide surgical margins were associated with a significantly better local control rate compared to marginal or intralesional margins. Tumor size did correlate with systemic but not local recurrence. Tumor site and histotype did not appear to have an impact on outcome. Chemotherapy did not show to have an impact on local or systemic control. Fourteen patients (12.5%) had local complications attributed to radiotherapy. Eleven patients developed wound-healing problems, which needed further surgery. Using our treatment algorithm for high-grade soft tissue sarcoma of the extremities, good local and systemic control can be achieved with a low complication rate.

Synovial chondromatosis in a lumbar apophyseal joint.

A 31-year-old woman presented with painful swelling in the right paravertebral region that had been present for 2 years. Radiography and CT revealed an area of increased density due to multiple calcifications localized at the fourth lumbar vertebra. Histological examination revealed that the lesion consisted of nodules of hyaline cartilage, with focal areas of calcification, growing within synovial tissue.