Purpose

Ewings sarcoma (EWS) is the second most common primary malignancy of bone. Five-year survival ranges between 50 and 70% for patients who present with localized disease. EWS occurs in both axial and appendicular locations. The prognostic importance of anatomic location (axial vs. appendicular) is unclear. The purpose of this study is to report a single institution experience in the management of patients with EWS, and to investigate anatomic location as a prognostic factor.

Purpose: Impending and pathologic fractures of the humerus, usually due to metastatic disease, are associated with significant pain, morbidity, loss of function, and diminished quality of life. Several methods of stabilization have been described. Here we report the outcome of fixation using intramedullary poly methyl methacrylate (bone cement) and non-locking plates.

Method: A retrospective review was undertaken which included all patients treated at a tertiary musculoskeletal oncology referral center from February, 1989 to October, 2009. Patients who underwent surgical management of an impending or pathologic fracture of the humerus were included. All patients were treated using the following technique: Vascular tumors were embolized pre-operatively. Following gross tumor removal through curettage, antibiotic bone cement was placed into the humeral canal and bone defect. If there was a fracture, the bone ends were held in place as the cement cured. The humerus was stabilized using non-locking plates fixed with screws inserted through the bone and hardened bone/cement composite. Ideally, plates spanned the osseous defect by at least 2 cortical diameters and often the entire length of the bone.

Results: Clinical records were available for 67 patients who underwent the above procedure. There were 44 males and 23 females with an average age of 62.2 years. In 76% of patients there was a pathologic fracture at presentation, while in 24% it was impending. The most common histology was myeloma (21%), followed by renal (20%) and lung adenocarcinoma (20%). Forty-nine patients (73%) had one plate, 16 (24%) had two plates, one patient had three plates, and one had four plates. Complications occurred in 14 (21%) cases, and eight (12%) required reoperation of the humerus. The most common cause for reoperation was disease progression (six of eight). There were two nerve palsies, one deep infection, and one hardware failure. Interestingly, the single hardware failure occurred in a patient whose pain relief and functional status improved to the point that he fractured his construct while hammering with the affected arm in a home improvement project.

Conclusion: Intralesional tumor resection and stabilization of impending and pathologic fractures of the humerus with the described technique has several attributes. Most importantly, it provides immediate, absolute rigidity of the upper extremity and enables early pain relief and return of function without the need for osseous union. Radiation has no negative effects on the construct. The patient’s local disease burden is reduced, thus helping to alleviate tumor-related pain and slow local disease progression. Finally, this technique is user-friendly and cost-effective as it does not require any special equipment or devices that are not available to community orthopaedic surgeons. This technique provides a durable option for the treatment of impending and pathologic humerus fractures.

Purpose: Massive endoprostheses have become the mainstay of treatment for reconstruction after resection of primary bone tumours. The Kotz Modular Femoral Tibial Replacement (KMFTR, Kotz prosthesis, Stryker Inc.) system has been one of the most widely utilized uncemented modular systems. Although this prosthesis has excellent bone ingrowth characteristics and a low aseptic loosening rate, we have identified a significant incidence of mechanical failure and breakage of the prosthesis. The purpose of this investigation is to review the outcomes after prosthetic revision for a broken Kotz prosthesis.

Method: A retrospective review was undertaken of our institutional database from the years 1989, when we first utilized the Kotz prosthesis, until present. We identified all patients who had undergone a revision of the prosthesis for mechanical failure or prosthetic breakage. Periprosthetic fractures and revisions for polyethylene bushing wear were excluded.

Results: 119 distal femoral, 55 proximal tibial and 47 proximal femoral Kotz endoprostheses (221 in total) have been implanted in our center since 1989. There were 21 revisions (9.5% of total prostheses) for mechanical failure. Of these, 16 were in the distal femur, four in the proximal tibia and one in the proximal femur. Mechanical failures occurred at a mean of 77 months (range 24–170). Of the 21 metal failures, 8 stems broke at the junction of the stem and body, 8 fractured through screw holes in the stem, 3 fractured the derotation lug, one fractured the tibial housing and one lateral side-plate failed. Of these failures only three implants had associated definite loosening and two of these three were cemented. Broken stems initially required extraction whilst preserving as much of the longitudinal and transverse bone stock as possible in order to facilitate osseo-mechanical integration of the revision prosthesis. This was accomplished using trephines to core the ingrown broken stem out of the bone. Over the last 20 years, the 16 broken stems have been revised in 5 patients to larger Kotz uncemented stems, 2 to cemented GMRS stems with an adaptor to the KMFTR system, 3 to Restoration uncemented revision hip stems with a custom adaptor to the KMFTR system, 2 to custom GMRS uncemented stems with an adaptor to the KMFTR system, and 4 to total femurs. All except one patient was alive with no evidence of disease. Post-revision, 14 patients had TESS, MSTS87, MSTS93 scores of 80.5, 25.5 and 70 respectively.

Conclusion: Despite very low aseptic loosening rates, mechanical failure of the Kotz prosthesis continues to be a significant clinical problem even several years after implantation. Fatigue failure often leads to the difficult scenario of removing a well-ingrown uncemented stem. Our data illustrates that these prostheses can often be successfully revised by trephining out the broken stem and inserting new uncemented stems. Functional outcome continues to be good and is comparable to pre-revision levels.