What Sport Activity Levels Are Achieved in Patients After Resection and Endoprosthetic Reconstruction for a Proximal Femur Bone Sarcoma?

With improvements in endoprosthesis design and materials and established principles of resection, limb salvage surgery is currently a common method to treat patients with sarcomas of the proximal femur [9]. The main goal for treatment of malignant tumors of the extremities is to maximize survival while preserving a functional limb when at all possible. However, recommendations of permanent limits of sports activities to lessen long-term prosthetic failures by reconstructive surgeons are variable from one surgeon to another [16]. Whereas many patients after elective joint replacement of the hip can still carry out sport activities, some tumor surgeons are reluctant to allow patients with these more complex reconstructions to participate in many athletic activities. Furthermore, activities of daily living, functional outcome, general health, and well-being may be compromised in survivors of bone sarcomas [3]. Some studies have demonstrated that sports activities have potential physical and mental benefits, which may be useful for rehabilitation in patients after bone sarcoma and may reduce the personal burdens of long-term survivors [30, 33]. This case series was selected to look at a specific anatomic site, the proximal femur, to provide information about sport activity levels and prosthetic failures in long-term survivors after proximal femur megaprostheses.

There are several limitations to this study. Most importantly, this study was small, and more than one-fourth of our patients (seven of 27 otherwise eligible patients) were unavailable for followup. The estimates of sports participation made in this study probably are best-case estimates, given that some patients were lost to followup; patients unaccounted for might not be doing as well as those represented here. As such, the degree to which sports participation influences implant durability remains, for the most part, unanswered; studies with more patients and longer followup will be needed to determine to what degree prosthesis survivorship relates to sporting activity levels. Our data were assessed by recall interview at a median of 18 years after the surgical intervention, which may have introduced recall bias regarding sports activities before diagnosis and at different followup time points. However, it is important to note that these patients seemed to accurately recall when they started to perform sports and at what level, indicating the importance of sports for these patients. As a result of the small size of our study population, several variables including gender and technical (trochanteric fixations, cups) and oncological (chemotherapy) issues could not be considered in a multivariable model. It is possible that patients downplayed their sports activities as a result of current recommendations by their surgeons, which were not standardized, and to perform primarily low-impact activities at our department because of the importance of sports activity in the life of a young person. Moreover, these current results, considering types of sports and workout times, might differ between countries and other cultural backgrounds. Our sample size is too small to give general recommendations with regard to sport activities; however, these data may provide information for future studies about sports activities and failures in survivors of malignant bone tumors. It is difficult to generalize these findings to other patients because of differences in the amount of muscle resected, variations in the type of endoprosthesis, and the overall health of the patients. We had a broad age range and sports information from a young person may differ substantially from an older person. We also have insufficient information about the desire of patients to do sporting activities; the ones who did not participate in sports may not have desired to do so rather than being restricted from sports because of complications or recommendations. Also, the findings in this study of patients from Austria may not be reflective of sports activities or desires of patients from other countries or cultures. Furthermore, during this long period between 1979 and 2010, some things could have changed, foremost the advice that was given to patients with regard to sport activity level based on surgeon experiences. Outcomes may reflect the physicians’ advice or beliefs rather than the actual ability. However, according to the principles of limb salvage, the advice the surgeons gave to their patients at our institution was that the limb “shall be moved,” and they have been encouraging them ever since to do moderate sports; they are also reminded that high-impact sports will not be possible, unfortunately without scientific background. However, there was not at all a correlation between followup period and sports activity levels; neither was there a difference between patients’ sports activity and different followups, reflecting that no time-related factors (eg, different techniques) might be involved in the followup of these patients.

This study showed that a high proportion of long-term survivors were active in sports activities. Interestingly, the patients included in this study appeared to be practicing sports that have been recommended after hip arthroplasty for arthritis in larger studies such as general walking (hiking), cycling or ergometer cycling, and swimming (crawl or paddling movements) [4, 35]. One patient started practicing golf during followup and two patients were continuously performing alpine skiing at the latest followup. These two sports are also recommended by hip surgeons, the latter primarily if the patient is already experienced in alpine skiing before surgery [12]. In comparison to the patients in this study, in a prior group of patients we studied with knee megaendoprostheses, sports activity before surgery did not seem to correlate with postoperative activity, although this could be the result of a beta error [18]. Furthermore, our available data showed no difference in long-term sports activity, whether patients were practicing sports before diagnosis or not.

The UCLA activity score reported a reduction in sports activity levels from 9 to 6 points at 3 years compared with preoperative activity and remained relatively stable thereafter. This level of 6 (“regularly participating in moderate activities”) after 3 years appears similar to that reported after 6 years after elective THA [26, 33]. One study showed that 43% of patients undergoing elective THA reached a UCLA score of over 7 one year postoperatively, which is described as “regularly participating in active events such as bicycling” and is supposed to be highly active. Approximately the same amount (38%) of our patients with megaprostheses ultimately reached this level 5 years postoperatively. One study even showed that patients with osteoarthritis improve their preoperative UCLA scores from 4.5 to approximately 6 after 1 year [35], whereas our patients treated for a tumor had UCLA scores of 9 before surgery and activity decreased to 3 one year postoperatively, which is seen as “sometimes participating in mild activities, such as walking, limited housework and limited shopping.” Interestingly, the patients reported a larger reduction in modified Weighted Activity Score (from 6 to 3 points) in the same time period. This is likely the result of the methodological “weighting” of different sports according to their impact and because of recommendations of their surgeons, which makes the loss of higher impact in sports or lowering of frequencies more obvious. The decrease from 6 to 3 median points reported by the modified Weighted Activity Score reflects on average moderate activity levels. According to the authors, a score of 9 and greater was defined as high activity [21]. In this current study none was performing any high-impact sport beyond 1 year from their procedure, although five of the patients reported participating in high-impact sports before surgery. We presume that there is a difference in expectations between patients after joint arthroplasty after osteoarthritis compared with patients receiving megaprosthetic reconstructions for bone tumors. Patients with osteoarthritis likely expect relief from preoperative pain and a relatively normal lifestyle, whereas patients with bone tumors appear to accept limitations and may be concerned about failure of their reconstruction so that they modify their activities. However, in terms of UCLA activity, six of 16 reported high activity (7–9 points) and in terms of modified Weighted Activity Score 3 of 16 reported high activity at long-term followup. This difference may lie in different frequencies, which have a decisive impact on modified Weighted Activity Score but not on UCLA. For example, patients with UCLA 7 “regularly participating in active events such as bicycling” can have higher or lower modified Weighted Activity Scores according to the frequency of bicycling. In terms of time and commitment in sport, seven of 16 patients after megaprostheses reached a mean of 3 hours/week sports activity, which is the recommended workout hours (4 hours/week) for healthy individuals [10].

Ollivier et al. reported that higher activity levels led to risk of implant failure and lower implant survivorship [25]. In this current study nine of 16 patients developed complications during their postoperative period and had revision surgery. Apart from a possible relationship of high activity and cup loosening (failure Type II) as well as mechanical disconnection of a module and loosening of the cone at another time (failure Type III), with the numbers of patients we had, we could not demonstrate an obvious sports-related association with prosthetic failures. Two patients were continuously practicing alpine skiing and did not shown negative effects on acetabular and femoral components so far, but with a larger number of patients and longer followup, it may be shown that a correlation does exist [12]. Similarly, the patients who took up playing golf after hip arthroplasty may also not lead to higher revision rates after hip arthroplasty, but we do not have a sufficient number of patients playing golf to know if the same is true for patients with tumor [19].

Our data can show that patients after tumor megaprostheses of the proximal femur can regularly play moderate sports and that long time periods are required to recover and adjust after operations of this magnitude but can reach comparable levels to patients after elective hip surgery after 5 years. However, the fact that patients can participate in sports with these implants does not mean that they should do so. Future studies will need to evaluate carefully–in the context of more complete, longer term followup of larger groups of patients–the degree to which sports participation might influence implant durability. With the numbers we had, we could not identify patient-specific factors predicting postoperative activity nor a relationship between type of surgery, implant, or surgical factors and activity levels. Sport activities may be an important part of some young persons’ lives, especially in a world of growing emphasis on mobility. Endoprosthetic implants for elective joint surgery attempt to adapt these requirements. Our data in this young cohort of patients suggest that there is a desire to participate in sports activities as reflected in the high number of patients participating in sports at 5-year followup, but this may not be true for all populations, cultures, or specific patients. With the numbers of patients we had, we could not show that sports was related to revision in survivors; however, failures resulting from higher activity levels with further followup cannot be excluded.