Use of endoprostheses for proximal femur metastases results in a rapid rehabilitation and low risk of implant failure--A prospective population-based study.

Dear Editor,

We read the article “Use of endoprosthesis for proximal femur metastases results in a rapid rehabilitation and low risk of implant failure. A prospective population- based study”, with great interest [1]. We complement the authors for doing a remarkable job in drawing the attention of orthopaedic surgeons worldwide to this complex and often neglected topic. However, there are some concerns with respect to the findings of the study that merit further input from the authors.

Firstly, the authors have chosen not to include closed reduction of a dislocated total hip arthroplasty as a revision procedure. The argument put forward was “that a procedure that requires few hours admittance (closed reduction) does not cause the same functional impairment for the patient as removal of an implant and thus is not relevant for comparison”. However, not all cases of dislocated hip can be successfully reduced by a closed manoeuvre. The literature [2,3] clearly states that approximately one third cases of dislocated total hip arthroplasty may require a trip to the operating room for revision surgery. This represents a significant percentage of patients undergoing endoprosthetic replacement for proximal femur metastases, which cannot be written off; rather it would have significant bearing on the surgical decision making and hence the outcome in this subgroup of patients.

Secondly, an important concern with regard to the study was the lack of functional outcome assessment in the patients who underwent internal fixation. We agree with the authors that it is a difficult population group to follow up and assess over a prolonged period of time. Yet, without an objective comparison between the functional scores of the two groups (internal fixation versus endoprosthesis), a statement of the best surgical procedure for this patient population cannot be put forward.

The proximal femur is one of the most common sites for bone metastases [4]. These lesions are associated with severe pain and a high incidence of pathological fractures [4]. Hence, timely and appropriate management either with internal fixation or arthroplasty is essential in order to preserve the quality of life in these patients. However, well designed randomized control trials are needed before a conclusion against internal fixation can be drawn.

Declaration of Competing Interest

The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.