Reconstruction with a double-constrained implant design after complex shoulder extra-articular resection.

BACKGROUND: Approximately, one-third of patients with tumors of proximal humerus will require an extra-articular resection to achieve oncologic margins. This procedure yields poor functional outcomes with a considerable rate of revisions. Unconstrained implants are prone to instability hindering also function of the elbow and hand, whereas constrained shoulder reconstructions suffer from early aseptic loosening of the glenoid component due to bone overload. The purpose of this study was to develop a constrained implant suitable for extra-articular resection with loss of function in deltoid and rotator cuff, which would provide both stability and passive motion, whilst also decreasing the risk of aseptic loosening of the glenoid component. METHODS: In cooperation with Czech Technical University in Prague, we devised an implant consisting of two constrained joints in series connected by a dumbbell piece. The biomechanical analysis showed a reduction of load transfer to the glenoid component with a torque of 8.6 Nm capable of generating an 865-N pulling force on bone screw to just 0.07 Nm, hence shielding the glenoid component from undesired forces and decreasing the risk of aseptic loosening. Three patients with extra-articular resection with a total loss of function of both rotator cuff and deltoid muscle received this type of reconstruction. The average follow-up was 16 months. RESULTS: The surgical technique is straightforward. The surgery took 175 min on average with average blood loss of 516 ml. There were no surgical- or implant-related complications. All three patients were pain-free and had a stable shoulder joint after the reconstruction. All had fully functional elbow, wrist, and hand joints. The average Musculoskeletal Tumor Society (MSTS) score was 21/30 (70%). All patients were pleased with the results. CONCLUSION: The presented innovative implant design has demonstrated to be a promising alternative for reconstruction in these challenging cases.

A quantitative CT analysis of fibula inlayed in a massive allograft for femoral diaphysis reconstruction.

Introduction: In diaphyseal reconstructions for bone tumor resection, massive bone allografts (MBA) are historically regarded as the gold standard. However, these are not without complications, and they present an elevated risk of infection, nonunion and structural failure that increases over time as the graft remains largely avascular. To counteract this disadvantage, a combination of allograft with a vascularized fibula has been proposed. The aim of our study was to objectively review the results of combined vascularized fibula-allograft constructs compared to plain allograft reconstruction for bone defects in tumor patients and to assess fibular vitality predictive factors from imaging studies. Materials and methods: Our data was retrospectively reviewed for patients with femoral diaphysis reconstructions in the past ten years. Ten patients (six males and four females) with a mean average follow-up time of 43.80 months (range 20-83, SD 18.17) with combined graft (Group A) were included in the study. As a control group 11 patients (six males and five females) with a mean average follow-up of 56.91 months (range 7-118, SD 41.33) with a simple allograft reconstruction were analyzed (Group B). Demographic and surgical data, adjuvant therapy as well as complications were analyzed in both groups. Both groups were assessed with plain radiographs for bony fusion at the osteotomy sites. Patients in "Group A" had consecutive CT scans at 6 months and then annually to check for potential bone stock and bone density changes. We analyzed total bone density as well as incremental changes in three different areas of the reconstruction. This was done at two defined levels for each patient. Only patients with at least two consecutive CT scans were included in the study. Results: There were no statistical differences between the groups in terms of demographics, diagnosis or adjuvant therapy (p = 1.0). The mean average surgical time (599.44 vs 229.09) and mean average blood loss (1855.56 ml vs. 804.55 ml) were significantly higher in the combined graft group A (p < 0.001 and p = 0.01, respectively). The mean average length of resection (19.95 cm vs. 15.50 cm) was higher in the combined graft group (p = 0.04). The risk for non-union and infectious complication was higher in the allograft group, however, the difference was not significant (p = 0.09 and p = 0.66, respectively). The mean average time to union at junction sites was 4.71 months (range 2.5-6.0, SD 1.19) for cases of successful fibula transfer, 19.50 months (range 5.5-29.5, SD 12.49) for the three cases where we presumed the fibula was not viable and 18.85 months (range 9-60, SD 11.99) for the allograft group. The difference in healing time was statistically significant (p = 0.009). There were four cases of non-union in the allograft group.Seven out of ten patients in Group A exhibited incremental changes in all CT scan measured values. This difference was statistically significant already at 18 months from the index surgery (p = 0.008). The patients with a non-viable fibula had a smaller increase in the percentage of total bone density area measured in the CT scan compared to those patients with a successful fibula transfer (4.33, SD 2.52 vs. 52.29, SD 22.74, p = 0.008). The average bone density incremental increase in-between the fibula and allograft was different among patients with an unsuccessful fibula transfer (32.22, SD 10.41) and the ones with a viable fibula (288.00, SD123.74, p = 0.009). Bony bridges were observed in six cases of viable fibula and in none of the tree presumably dead fibulas (p = 0.03). The mean average MSTS score was higher for the subgroup of successful fibular transfer (26.7/30, SD 2.87) when compared to the group of non-viable fibular graft (17.00/30, SD 6.08) and this was also statistically significant (p = 0-007). Conclusion: A viable fibula enhances incorporation of the allograft and decreases the risk for both structural failure as well as infectious complications. Viable fibula also contributes to better functional status of the recipient. Consecutive CT scans proved to be a reliable method for assessing fibular vitality. When no measurable changes are present at 18-month follow-up, we can declare the transfer unsuccessful with a good amount of certainty. These reconstructions behave as simple allograft reconstructions with analogue risk factors. The presence of either axial bridges between the fibula and allograft or newly formed bone on the inner surface of the allograft is indicative of a successful fibular transfer. The success rate of fibular transfer in our study was only 70% and skeletally mature and taller patients seem to be at increased risk for failure. The longer surgical times and donor site morbidity therefore warrant stricter indications for this procedure.

Cement Intercalary Reconstruction After Bone Tumor Resection.

The optimal type of reconstruction after intercalary tumor resection is unclear. Megaprosthetic and biologic reconstructions may restore bone stock, but their complexity may result in complications and delays in rehabilitation and initiation of adjuvant treatment. Instead, cement spacer permanent reconstruction can be performed as index surgery. The authors studied the files of 20 patients who had bone tumors of the humerus and femur and underwent wide margin resection and permanent cement spacer intercalary reconstruction. Mean follow-up was 52 months (range, 2-255 months). The authors evaluated the survival and function of the patients and the outcome of the cement spacer reconstructions. Five patients who had metastatic bone disease died of their disease with their cement spacer reconstruction in place without complications. One patient who had bone sarcoma experienced a local recurrence that was treated with hip disarticulation. Three patients who had bone sarcomas were converted to biologic reconstruction because of disease remission and had improved prognosis without complications related to cement spacer reconstruction. Two patients experienced mechanical failure of femoral reconstruction and underwent revision with an intercalary biologic reconstruction. No patient who had a cement spacer humeral reconstruction experienced a complication, and no patient experienced infection of the reconstruction. Mean Musculoskeletal Tumor Society score of the patients with cement spacer humeral and femoral reconstructions was 85% and 82%, respectively. [Orthopedics. 2021;44(4):e593-e599.].

Chondrosarcomas of the small bones: analysis of 44 patients.

BACKGROUND: Chondrosarcomas of the small bones of the hands and feet are uncommon and account for less than 2% of all chondrosarcomas in the skeleton; a 4.2% rate of malignant degeneration of enchondromas to secondary chondrosarcomas has been reported. We performed this study to assess the outcome of the patients with chondrosarcomas of the small bones. We hypothesized that the presumed better prognosis of chondrosarcomas in these locations could be biased as the majority of these tumors tend to be of lower grades and are removed when still small sized, and that less aggressive surgery has an adverse effect on local control MATERIALS AND METHODS: We retrospectively studied the files of 44 patients with chondrosarcomas of the small bones of the hands and feet. There were 23 female and 21 male patients with a mean age of 50.9 years (range, 6-86 years). The mean follow-up was 13 years (range, 5-40 years). We recorded the patients' details including gender and age at diagnosis, type and duration of symptoms, tumor location and histology, type of surgery and complications, and outcome (local recurrences and metastases). RESULTS: The most common anatomical location for chondrosarcomas of the hands was the metacarpals and proximal phalanges. The most common presenting symptom was a slowly enlarging palpable mass. Overall, 36 chondrosarcomas were secondary to a pre-existing cartilaginous tumor. Patients with syndromes were affected in younger age compared to the others. The mean age at diagnosis was higher for higher grade chondrosarcomas. Overall, 13 patients (29.5%) experienced a local recurrence; the rate of local recurrence was higher after curettage regardless the histological grade of the tumors. After wide resection of the first local recurrence, five patients experienced local re-recurrence. Five patients (11.4%) experienced lung metastases, two patients at presentation. All these patients had a high grade chondrosarcomas. At the last follow-up, one patient with lung metastases died from disease, and another patient died from unrelated cause. CONCLUSIONS: The patients with chondrosarcomas of the small bones of the hands and feet may have a dismal outcome if treated improperly. A careful treatment planning is required to avoid unnecessary amputations. Curettage is associated with a high rate for local recurrence that should be treated with a more aggressive surgical resection to avoid re-recurrences. Although the risk is low, the patients may develop lung metastases, especially those with higher grade chondrosarcomas, therefore, they should be staged and followed closely.

Complex surgery for locally advanced bone and soft tissue sarcomas of the shoulder girdle.

Surgical management of primary musculoskeletal tumors of the shoulder girdle is cognitively and technically demanding. Over the last decades, advances in the medical treatments, imaging and surgical techniques have fostered limb salvage surgery and reduced the need for amputation. Despite well-accepted general principles, an individualized approach is often necessary to accommodate tumor extension, anatomical challenges and patient characteristics. A combination of techniques is often required to achieve optimal oncologic and durable functional outcome. Goal of this article is to review approach and management of patients with locally advanced sarcomas of the shoulder girdle requiring major tumor surgery, to illustrate principles of surgical strategy, outcome and complications, and to provide useful guidelines for the treating physicians.

Intercalary reconstructions after bone tumor resections: a review of treatments.

An intercalary reconstruction is defined as replacement of the diaphyseal portion of a long bone after segmental skeletal resection (diaphysectomy). Intercalary reconstructions typically result in superior function compared to other limb-sparing procedures as the patient's native joints above and below the reconstruction are left undisturbed. The most popular reconstructive options after segmental resection of a bone sarcoma include allografts, vascularized fibula graft, combined allograft and vascularized fibula, segmental endoprostheses, extracorporeal devitalized autograft, and segmental transport using the principles of distraction osteogenesis. This article aims to review the indications, techniques, limitations, pros and cons, and complications of the aforementioned methods of intercalary bone tumor resections and reconstructions in the context of the ever-growing, brave new field of limb-salvage surgery.

Tumors of the hand.

Tumors of the hand comprise a vast array of lesions involving skin, soft tissue and bone. The majority of tumors in the hand are benign. Malignant tumors, although rare, do occur and frequently have unique characteristics in this specific anatomic location. Careful staging, histological diagnosis and treatment are essential to optimize clinical outcome. However, straightforward most of the time, hand tumor management does have pitfalls; caution is advised, as a missed or delayed diagnosis or an improperly executed biopsy may have devastating consequences. This article reviews the clinical spectrum of the most common benign and malignant bone and soft tissue tumors of the hand and discusses the clinicopathological findings, imaging features and current concepts in treatment for these tumors.

Distraction osteogenesis reconstruction of large segmental bone defects after primary tumor resection: pitfalls and benefits.

Successful cure is achieved in almost 70% of patients with primary bone sarcomas with currently available therapies. Some soft tissue sarcomas require wide bone resection in order to achieve appropriate margins for cure of disease, and patients undergoing these procedures need durable reconstruction. Biological reconstruction has been shown to provide patients with superior long-term results over other alternatives. Distraction osteogenesis is well studied in the correction of deformities as well as in addressing some congenital musculoskeletal pathologies. The use of this technique in tumor settings has been avoided by many surgeons for a multitude of concerns, including infection risk, potential tumor activation, and uncertainty regarding the effect of systemic therapy on the callus regenerate. We review the use of this reconstruction technique using cases from our institutional experience to illustrate its incorporation into the successful management of orthopedic oncology patients. Distraction osteogenesis is an effective method for reconstructing even large bony defects and is safe in the setting of systemic therapy. This technique has the potential to address some of the common problems associated with orthopedic oncology resection, such as infection and leg length discrepancy.

Atypical lipomatous tumors/well-differentiated liposarcomas: clinical outcome of 67 patients.

Atypical lipomatous tumors/well-differentiated liposarcomas are low-grade malignant mesenchymal neoplasms with high propensity to local recurrence and potential to dedifferentiate to higher grades over time. However, the published risks of local recurrence and dedifferentiation vary, and no unified treatment and follow-up plan has been accepted. We performed a study to evaluate the long-term clinical behavior and proper treatment and follow-up strategy for these tumors. We retrospectively reviewed the files of 101 patients treated between 1990 and 2008 with the diagnosis of atypical lipomatous tumors/well-differentiated liposarcomas. For 67 of these patients, complete data and 2-year minimum follow-up were available and were included in the study; 47 patients (group A) had primary surgical treatment at our institution and 20 patients (group B) were referred after ≥1 local recurrences. Mean follow-up was 81 months (range, 24-229 months). The local recurrence rate of primary atypical lipomatous tumors/well-differentiated liposarcomas was 10.6% (5/47 group A patients). The local re-recurrence rate of the recurrent atypical lipomatous tumors/well-differentiated liposarcomas was 52% (13/67 group A and B patients). Recurrences developed as late as 140 months after diagnosis and treatment. The rate of dedifferentiation at recurrences was 4% (1/25 group A and B patients with recurrent tumors). No patients developed metastases. Atypical lipomatous tumors/well-differentiated liposarcomas are associated with an increased rate of local re-recurrence and low risk of dedifferentiation at recurrences. Long-term follow-up is recommended for early diagnosis and treatment of local recurrences.