Long-term follow-up of custom cross-pin fixation of 56 tumour endoprosthesis stems: a single-institution experience.

AIMS: Aseptic loosening is a major cause of failure in cemented endoprosthetic reconstructions. This paper presents the long-term outcomes of a custom-designed cross-pin fixation construct designed to minimize rotational stress and subsequent aseptic loosening in selected patients. The paper will also examine the long-term survivorship and modes of failure when using this technique. PATIENTS AND METHODS: A review of 658 consecutive, prospectively collected cemented endoprosthetic reconstructions for oncological diagnoses at a single centre between 1980 and 2017 was performed. A total of 51 patients were identified with 56 endoprosthetic implants with cross-pin fixation, 21 of which were implanted following primary resection of tumour. Locations included distal femoral (n = 36), proximal femoral (n = 7), intercalary (n = 6), proximal humeral (n = 3), proximal tibial (n = 3), and distal humeral (n = 1). RESULTS: The median follow-up was 132 months (interquartile range (IQR) 44 to 189). In all, 20 stems required revision: eight for infection, five for structural failure, five for aseptic loosening, and two for tumour progression. Mechanical survivorship at five, ten, and 15 years was 84%, 78%, and 78%, respectively. Mechanical failure rate varied by location, with no mechanical failures of proximal femoral constructs and distal femoral survivorship of 82%, 77%, and 77% at five, ten, and 15 years. The survivorship of primary constructs at five years was 74%, with no failure after 40 months, while the survivorship for revision constructs was 89%, 80%, and 80% at five, ten, and 15 years. CONCLUSION: The rate of mechanical survivorship in our series is similar to those reported for other methods of reconstruction for short diaphyseal segments, such as compressive osseointegration. The mechanical failure rate differed by location, while there was no substantial difference in long-term survival between primary and revision reconstructions. Overall, custom cross-pin fixation is a viable option for endoprosthetic reconstruction of short metaphyseal segments with an acceptable rate of mechanical failure. Cite this article: Bone Joint J 2019;101-B:724-731.

Patellar metastasis from a squamous carcinoma of the lung: a case report.

Bone is a common site of metastasis from lung cancer. Metastasis to the patella, however, is rare. A 76-year-old man presented with knee pain caused by an isolated patellar metastasis from squamous cell carcinoma of the lung. Treatment was delayed secondary to delay in diagnosis. In cases of bone pain that are unexplained or out of proportion to a traumatic event, more extensive diagnostic studies should be done.

Soft tissue echinococcosis: a report of two cases and review of the literature.

Echinococcosis (hydatid cyst disease) is a zoonotic infection caused by the parasitic tapeworm Echinococcus. The larval stage of this parasite can implant in many organs of the body, most commonly the liver, and create internal budding cystic masses. Echinococcal cysts also can implant in soft tissues; however, a review of the literature revealed no published case with the patient initially presenting with a soft tissue mass. Two such cases are reported in the current study. Physicians who evaluate soft tissue masses, particularly in patients from Echinococcus-endemic areas, need to include echinococcosis in their differential diagnoses. The current treatment of choice for soft tissue echinococcosis is wide resection combined with perioperative medical therapy.

Tibial turn-up for long distal femoral bone loss.

Since 1990, seven patients have been treated by the authors with the tibial turn-up procedure. They have ranged in age from 8 to 37 years; four were skeletally mature adults and three were children. All seven patients were faced with a clinical situation that required surgical removal of a long portion of their affected distal femur. Three of the adult patients initially were treated for osteosarcoma with long distal femoral resections and allograft arthrodesis of the knee. The allografts ultimately failed, two because of aseptic failure and one because of infection. One patient required distal femoral removal for chronic osteomyelitis and pathologic fracture. Of the three children who were treated, two had turn-ups after long resection of the distal femur for bone malignancy, and one had a secondary turn-up after failure of a long distal femoral endoprosthesis. The technique uses the normal ipsilateral tibia as a vascularized pedicle graft to restore femoral length. The ultimate result, even after very high above knee resection, is a long above knee amputation stump. The followup of the patients in the current study ranged from 2 to 8 years. All patients achieved healing and were able to wear above knee prostheses. The tibial turn-up is an effective procedure that results in a long functional above knee amputation stump even after very high above knee resections.

Imaging of surgical paraphernalia: what belongs in the patient and what does not.

Many radiologists are not familiar with the names of various instruments, surgical sponges, and needles that may be seen on intraoperative and postoperative radiographs. These devices may be intentionally placed for localization or therapeutic intervention, discovered on radiographs obtained to evaluate incorrect sponge or needle counts, or incidentally encountered on postoperative radiographs. These paraphernalia are usually described in vague nonspecific terms in radiology reports. In this article, photographs and radiographs of several instruments commonly used for intraoperative localization or therapy are presented, as well as examples of sponges, needles, and other devices that should not be found on postoperative radiographs. Familiarity with their appearances will allow a more precise and knowledgeable description in radiology reports.

Primary osteosarcoma of a metatarsal bone.

Although osteosarcoma is the most common primary bone malignancy of childhood and adolescence that is not related to marrow cells, involvement of the short tubular bones is uncommon. In contrast to more conventional sites, where the tumor is usually high grade and found in adolescents, osteosarcoma of the small bones is more likely to be low grade, and is often seen in older individuals. We present a case of low-grade primary osteosarcoma of a metatarsal bone in a 25-year-old woman.

Expandable endoprosthesis reconstruction in skeletally immature patients with tumors.

Between September 1984 and January 1996, 32 expandable endoprostheses were used for limb reconstruction after resection of malignant bone tumors in patients who were skeletally immature. The 20 boys and 12 girls ranged in age from 3 to 15 years (mean, 9.7 years). One patient had a Stage IIA tumor, 22 patients had Stage IIB tumors, and seven patients had Stage III tumors according to the classification of the Musculoskeletal Tumor Society. There also were two patients with parosteal osteosarcomas. The histologic diagnosis was osteosarcoma in 23 patients and Ewing's sarcoma in nine. All patients except the patients with parosteal osteosarcoma received standard neoadjuvant therapy. Twenty-two Lewis Expandable Adjustable Prostheses, four modular Wright Medical prostheses, four modular Howmedica prostheses, and two Techmedica expandable prostheses were used. Thirteen patients died, two have no evidence of disease, and 17 are continuously disease free. Sixteen of 32 patients (50%) have not had an expansion procedure because of early death in 10 and early amputation in three. Three patients are waiting to undergo an expansion procedure. Sixteen of the 32 patients (50%) have undergone 32 expansion procedures, to a maximum of 9 cm, without any infection. To maintain range of motion before the expansion procedure, a complete resection of the pseudocapsule was done routinely. Fourteen of the 32 patients did not have complications. Eighteen of the 32 patients had 27 complications. All Lewis Expandable Adjustable Prosthesis endoprostheses and the two nonmodular Techmedica prostheses were associated with a large amount of titanium debris. The children's functional results were similar to the results reported for adults with an average Musculoskeletal Tumor Society rating of good to excellent at the knee, fair to good at the hip, and fair about the shoulder. Rehabilitation of the knee in very young patients (5-8 years) remains problematic and careful selection of patient and family is necessary. The Lewis Expandable Adjustable Prosthesis probably should be reserved for very young patients (5-8 years) and modular systems should be used for large preadolescent and adolescent children.

Primary musculoskeletal neoplasms: effectiveness of core-needle biopsy.

PURPOSE: To analyze the effectiveness of core-needle biopsy for evaluation of possible primary musculoskeletal neoplasms, which often are evaluated with open biopsy. MATERIALS AND METHODS: Core-needle biopsy was performed at a tertiary care institution in 141 patients suspected of having a mesenchymal neoplasm. In 85 patients, the lesion was in soft tissue; in 56 patients, the lesion was in bone. Eighty-nine patients had a malignant lesion, and 52 had a benign lesion. Twenty-eight patients had undergone previous surgery. RESULTS: In 105 (74%) patients, core-needle biopsy results were concordant with results from specimens subsequently obtained at surgery with respect to tumor histologic features and grade, or they provided sufficient diagnostic information to obviate surgery. In 36 (26%) patients, inaccurate core-needle biopsy results were obtained: In nine, results were imprecise about exact histologic features; in three, results were correct about histologic features but incorrect about tumor grade. In 25 (18%) patients, open biopsy was performed after core-needle biopsy. The accuracy and rate of performance of open biopsy for soft-tissue lesions were not significantly different from those for bone lesions. CONCLUSION: Percutaneous core-needle biopsy can be an effective alternative to open biopsy in the evaluation of possible mesenchymal neoplasms of either bone or soft tissue. Needle biopsy of such lesions, however, is best performed as part of a multidisciplinary team approach to tumor management.

Endoprosthetic reconstruction for malignant upper extremity tumors.

Between December 1980 and December 1992, 59 patients underwent 60 reconstructions with endoprostheses after resection of malignant tumors in the upper extremity. There were 32 male patients and 27 female patients, with a mean age of 33 years (range, 3-83 years). The type of reconstruction was based on the location of the primary tumor site. The histologic diagnoses included osteosarcoma, chondrosarcoma, Ewing's sarcoma, malignant fibrous histiocytoma, soft tissue sarcoma, and fibrosarcoma of bone. Most of the patients had Stage IIB disease (N = 38), as established by the Musculoskeletal Tumor Society classification. An additional six patients had metastatic tumors to the upper extremity. Twenty-seven of 59 patients died of disease progression. Two patients died of other causes (chronic leukemia, human immunodeficiency virus infection). The 30 survivors had a mean followup of 90 months (range, 60-170 months). The Musculoskeletal Tumor Society functional analysis for the patients with a minimum 2-year followup (N = 41) averaged 74%. Sixteen of the 59 (27%) patients had local complications. Problems related to mechanical failure and infection were managed successfully with second operation. Amputation was rare, occurring in three of 60 (5%) patients and was related only to local recurrence. Endoprosthetic reconstructions of the upper extremity after tumor resections have proven to be successful.

Etiology and results of tumor endoprosthesis revision surgery in 64 patients.

From December 1980 to December 1995, 278 patients underwent primary custom endoprosthesis replacements for neoplastic disease at the University of California, Los Angeles and have been followed up for a minimum of 2 years or to death. The endoprosthesis reconstruction failed in 64 patients, including 10 additional patients referred for revision of their replacements. Failure was defined as the complete removal of a prosthesis for any reason. The cause of failure were aseptic loosening (44%), fatigue fracture (16%), local recurrence (14%), infection (13%), and failure of the expansion mechanism (6%). Forty-eight of 64 failed endoprostheses were managed by endoprosthesis reconstruction with most being revised using the same type of prosthesis. Nine of these patients with failed replacements experienced a second failure and four went on to require an amputation. Aseptic loosening and mechanical failure accounted for most of the failures and they were revised successfully. Sixty percent of the infected cases were salvaged satisfactorily by endoprosthetic revision, whereas, 89% of the local recurrences resulted in amputation. Based on endoprosthesis survival the 7-year failure rates were 31% and 34% for primary and revision reconstructions, respectively. The functional results for the patients with endoprosthesis revisions either were better, unchanged, or on average only slightly lower than results of patients with a surviving endoprosthesis.

Large, deep, high-grade extremity sarcomas: treating tumors of the flexor fossae.

Limb salvage is now possible for the majority of patients with extremity sarcomas. Although overall prognosis is primarily based on tumor size and histologic grade, complete surgical excision and local control is essential for cure. There are, however, certain anatomic locations such as the flexor fossae in which a complete surgical margin is difficult to attain, and surgery without adjuvant therapy has a high local failure and amputation rate. We have found that preoperative adjuvant therapy consisting of chemotherapy and radiation followed by surgical excision with tumor-free margins has been successful in treating flexor fossa sarcomas with high limb salvage (96%), local control (89%) and overall survival rates (70%). These results are comparable to patients with similar large, high-grade extremity tumors in other compartmental locations.

Surface lesions of bone.

A surface lesion of bone may arise within the cortex, between the cortex and the periosteum, within the periosteum, or in the tissues immediately adjacent to the periosteum including tendinous and ligamentous attachments. While these lesions generally reflect the spectrum of more common intramedullary lesions and have an appearance similar to that of their intramedullary counterparts, their unusual surface origin often renders diagnosis difficult. Surface sarcomas are usually of a lower grade than that of the intramedullary tumor, and often they have a more favorable prognosis. Traumatic lesions of the bone surface are common and should be considered in the differential diagnosis of a surface lesion, especially in the young or athletic individual. An elevated peripheral white blood cell count and erythrocyte sedimentation rate may herald an infection of the bone surface.

Loosening of massive proximal femoral cemented endoprostheses. Radiographic evidence of loosening mechanism.

A review of the radiographs of 24 patients with massive proximal femoral cemented tumor endoprostheses revealed a repetitive radiographic sequence that culminated in implant loosening. The initial step was osteolysis of the proximal femur at the bone-prosthesis junction (13 of 24 cases, 54%). The osteolysis then progressed into the adjacent periprosthetic bone-cement interface as a radiolucent line (5 of 24 cases, 21%), followed by extension along the stem, culminating in implant loosening (4 of 24 cases, 17%). Two prostheses (8%) have required revision for loosening. The proximal osteolysis was noted prior to the appearance of progressive periprosthetic radiolucent lines in 11 patients and simultaneously in 2 but never followed periprosthetic radiolucent lines (P < .05). These findings are consistent with loosening by debris-induced osteolysis. This loosening sequence, confirming previous observations of cemented component loosening, should encourage efforts to prevent or delay the onset of this sequence.

Antibiotic prophylaxis and infection resistance of massive tumor endoprostheses during chemotherapy.

Fifty-five consecutively treated patients with malignant bone tumors had preoperative and postoperative chemotherapy by one oncologist. These same patients had massive bone resection and cemented endoprosthetic bone replacement by one orthopaedic oncologist. Despite 143 instances of documented fever and/or neutropenia in 45 of these 55 patients, no known deep periprosthetic infections developed in any patient during follow-up (mean, 29.4 months; median, 25 months; range, 5 months to 62 months). Broad spectrum antibiotics had been administered in at least 118 instances to these patients (intravenously in hospital, 9 times to 7 patients; intravenously at home, 38 times to 18 patients; and orally at home, 71 times to 26 patients). This study confirms the low infection rate of these massive endoprostheses, despite neutropenic and/or febrile episodes if the patient is given prophylactic broad spectrum antibiotics during the episodes. We support the continued use of massive endoprostheses for bone reconstruction in patients requiring chemotherapy.

Stride analysis after proximal tibial replacement.

Ten patients who had undergone primary intraarticular proximal tibial replacement between April 1985 and December 1994, and had a minimum of 2 years of followup, were available for stride analysis. Mean age, time since intraarticular proximal tibial replacement, height, and weight were 23.8 years, 6.5 years, 167 cm, and 63 kg, respectively. A volunteer control group of five male patients who had undergone above knee amputation was obtained from the local community. The mean age, time since above knee amputation, height, and weight were 43.6 years, 24.1 years, 165 cm, and 70 kg, respectively. Stride analysis was performed over the central 6-m portion of a 10-m walkway at a self selected, comfortable pace. Gait velocity, stride length, cadence, and stance time symmetry were measured. Velocity after intraarticular proximal tibial replacement versus above knee amputation was 79.2 +/- 7.6 m per minute versus 71.4 +/- 5.4 m per minute. Cadence after intraarticular proximal tibial replacement versus above knee amputation was 112.4 +/- 10.6 steps per minute versus 110.1 +/- 2.4 steps per minute. There were no significant differences between stride length (1.41 +/- 0.13 m versus 1.43 +/- 0.12 m) and stance time symmetry (0.90 +/- 0.07 versus 0.87 +/- 0.11) for intraarticular proximal tibial replacement versus above knee amputation. The results suggest that endoprosthetic reconstruction resulted in a gait comparable with that after above knee amputation with an external prosthesis.

In vivo rotational stability of the kinematic rotating hinge knee prosthesis.

The in vivo rotary laxity and torsional stiffness of the knee joint were measured in 20 patients with wide intraarticular resection of the distal femoral tumor followed by reconstruction with a custom Kinematic rotating hinge endoprosthesis. The contralateral normal knee served as natural control. Twenty patients underwent 29 measurements, including 9 at the first year, 10 at the second year (4 of these also measured at year 1), and 10 at the third year (3 of these also measured at years 1 and 2; 2 also measured at year 2). The mean followup for the 15 survivors was 134 months (range, 102-156 months). The total rotatory laxity of the hinged knee was significantly greater than that of the contralateral knee. The torsional stiffness in external rotation of the hinged knee was 30.4% less than that of the contralateral knee in the first postoperative year, whereas the torsional stiffness in internal rotation was similar to that of the contralateral knee. Torsional stiffness of the hinged knee in the second year was significantly less than that of the contralateral knee whereas it was within the normal range of stiffness in the third year. The total rotatory laxity and torsional stiffness of the hinged knee in the early postoperative years could not predict the risk of late loosening. In vitro rotational stability of the rotating hinge device with axial load bearing was 6.7 and 8.1 Newton-meters (N-m) at 0 degrees and 20 degrees knee flexion, respectively, under an axial tibial load of 945 Newtons.

A modular endoprosthetic system for tumor and non-tumor reconstruction: preliminary experience.

Though originally designed to facilitate the management of primary malignant bone tumors, the indications for the Howmedica Oncology modular endoprostheses have expanded to include the reconstruction of metastatic lesions, failed internal fixation of difficult trauma problems, and failed conventional and custom tumor endoprostheses. Between July 1989 and August 1992, 24 patients underwent 25 procedures, either proximal humeral replacement (7), proximal femoral replacement (5), distal femoral replacement (9), or total femoral replacement (4). Diagnoses included primary bone tumor (6), metastases (5), and failed previous orthopedic intervention (14). Two early and four late complications in five patients were all treated successfully with surgical or nonoperative treatment. Preliminary functional results indicate very satisfactory results. Modular endoprostheses appear to be effective in the treatment of a wide range of diagnoses, not limited to the reconstruction following primary malignant bone tumor resections.

Urethral carcinoma metastatic to bone: a case report and literature review.

Distant urethral carcinoma metastasis is a very rare event. The following discussion presents a unique case of urethral carcinoma (adenocarcinoma) metastatic to bone and reviews the literature regarding this condition.