Archives of Physical Medicine and Rehabilitation
Volume 88, Issue 7 , Pages 885-890, July 2007

Sports Activities and Endurance Capacity of Bone Tumor Patients After Rotationplasty

  • Axel Hillmann, MD

      Affiliations

    • Orthopaedic Department, Klinikum Ingolstadt, Ingolstadt, Germany
    • Corresponding Author InformationReprint requests to Axel Hillmann, MD, Dept of Orthopedics, Klinikum Ingolstadt, Krumenauer Str. 24, 85049 Ingolstadt, Germany
    • ,
  • Roger Weist, MD

      Affiliations

    • Trauma and Orthopaedic Department, General Hospital Eilbek Hamburg, Hamburg, Germany
    • ,
  • Albert Fromme, MD

      Affiliations

    • Institute of Sports Medicine, University Hospital Münster, Münster, Germany
    • ,
  • Klaus Völker, MD

      Affiliations

    • Institute of Sports Medicine, University Hospital Münster, Münster, Germany
    • ,
  • Dieter Rosenbaum, PhD

      Affiliations

    • Movement Analysis Lab, Orthopeadic Department, University Hospital Münster, Münster, Germany.

Article Outline

Abstract 

Hillmann A, Weist R, Fromme A, Völker K, Rosenbaum D. Sports activities and endurance capacity of bone tumor patients after rotationplasty.

Objectives

To investigate the preferred types of sports activities of patients with rotationplasty and to measure their physiologic performance characteristics through treadmill ergometry.

Design

Cross-sectional, descriptive analysis and repeated measures of different velocities.

Setting

Biomechanics research laboratory.

Participants

Patients (n=61) with rotationplasty after bone tumor surgery, 30 of whom participated in a functional trial (treadmill), and a control group (n=20).

Interventions

Not applicable.

Main Outcome Measures

Patients’ participation in sports compared with that of the healthy population, treadmill performance at 2 or 3 different speeds, heart rate, lactate accumulation, oxygen consumption, ventilatory equivalent, efficiency, respiratory minute volume, and respiratory quotient.

Results

High activity in sports participation (85%) in most common sports (8 competitive, 17 sports club members, the remaining subjects were recreational athletes). At the same treadmill speed, lactate accumulation and all cardiorespiratory functions were higher in rotationplasty patients than in the control group.

Conclusions

Patients can re-engage in a high level of physical activity after rotationplasty for bone tumor treatment. This physical activity is necessary if patients want to maintain or improve a desired level of sports activity.

Key Words: Bone neoplasms, Cardiovascular system, Ergometry, Physical endurance, Rehabilitation, Sports, Treadmill test

 

THE KNEE REGION is the most common site for bone tumors, especially osteosarcoma.1 Along with multimodal chemotherapy, surgical options are important in the treatment regimen. In addition to ablative procedures, limb salvage surgery can be considered the treatment of choice.2 Gait analysis studies3, 4, 5, 6 and evaluations of the quality of life (QOL)7, 8 have demonstrated that rotationplasty is at least comparable, if not superior, to limb salvage. After surgery, many patients are concerned about their physical capabilities and level of sports performance, which are important issues in reintegrating into a normal social life. For patients who were treated with a rotationplasty after wide resection of a tumor in the knee region, sports activities such as cycling, downhill skiing, tennis, and soccer are considered possible and without injury risk as soon as muscular control over the new “knee” joint can be expected.9, 10, 11 Specially designed prostheses also enable patients to swim.12, 13 Other than these general recommendations, however, there is no detailed information about the actual sports and functional activity levels that these patients can achieve.

Spiroergometric analyses after ablative extremity surgery indicate that the resection level has a marked influence on maximal aerobic capacity. Patients in 1 study14 demonstrated an energetically more efficient gait after rotationplasty than did patients who underwent amputations. Fowler et al15 found that after rotationplasty, children could run faster with less oxygen consumption than could an age-matched control group that had Syme’s amputations. Cammisa et al16 found that the relative energy cost of walking at self-selected speeds in rotationplasty patients was significantly higher than in a healthy control group, but was significantly lower than the cost for above-knee amputees. There was no difference in patients with endoprosthesis. Van der Windt et al17 could not detect a difference in energy expenditure in children after rotationplasty, knee amputation, or hip disarticulation. Cummings et al18 found that the length of the prosthetic shaft apparently had no influence on oxygen consumption; only cardiorespiratory training had a pronounced influence on cardiorespiratory capability. James19 discussed higher lactate levels as an indication for an increased level of anaerobic metabolism and higher oxygen consumption during locomotion after above-knee amputation. Oxygen consumption remained the same in quiet standing.19

The functional capacity of tumor patients is commonly evaluated with the Musculoskeletal Tumor Society rating, according to Enneking et al.20 Function is described in 6 categories that are related to activities of daily living, pain, need for support, and subjective satisfaction, but the score does not consider the level of sports activities. Participation in sports is important for its cardiopulmonary benefits as well as for its sociologic aspects. This issue has not been evaluated in a large sample of rotationplasty patients, however. Therefore, our purpose in this study was: (1) to evaluate the sports activities in which patients who underwent rotationplasty are actively engaged; and (2) to examine the physiologic performance level of these patients through respiratory and metabolic measurements during treadmill exercise.

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Methods 

A total of 61 patients with rotationplasty (35 men, 26 women) were questioned about their activity level in various sports. We asked about their participation in school, leisure, and competitive sports activities, with the last named category being characterized by active participation at a competitive level. In addition, we sought information about whether they had active membership in a typical sports club or one that was established to help train those with disabilities.

Furthermore, 30 (14 men, 16 women) of the 61 patients volunteered to participate in a clinical and functional follow-up investigation of their sports performance at the Orthopaedics Department and the Institute of Sports Medicine of the University Hospital Münster. For personal reasons (eg, long travel distance), the remaining subjects (n=31) were unable or unwilling to report to the biomechanics lab for physiologic evaluation. The average age of the patients was 23.7±8.8 years (range, 7−54y) at follow-up. The average weight was 63.6±17.3kg and the height was 172.6±14.4cm. The results were compared with a control group of 21 healthy subjects (12 men, 9 women) with a mean age of 25.9±8.7 years (range, 8−42y), mean height of 176.8±14.3cm, and mean weight of 70.3±15.9kg. There were no significant differences between the groups with respect to age, height, or body weight. Statistical tests were performed with commercial softwarea; we used the Mann-Whitney U test for nonparametric comparisons between the 2 groups, with an α level at P less than .05.

Twenty-two patients underwent A1 rotationplasty, according to the Winkelmann criteria.21 Only 1 patient had a type A2 rotationplasty. Six patients had received a hip rotationplasty type BI (n=1) or BII (n=5); the youngest patient had a BIIIa rotationplasty. The groups were too small and inhomogeneous to allow statistical comparisons among the different types of rotationplasty.

The patients and control subjects completed walking trials on a motor-driven treadmillb at 2 or 3 different speeds, depending on their capabilities. The required walking distance was 400m at each speed. Participants were given a resting period of 8 minutes between the sessions. Because of the marked differences in treadmill velocity reported in previous studies, we adhered to a previously used protocol with the same 3 velocities (slow, .67m/s; comfortable, 1.0m/s; fast, 1.67m/s)22 and compared the results with those of a control group of similar age and sex.

In the first part of the experimental session, blood lactate concentration at rest was determined from a capillary blood sample taken from the ear lobe.c At each treadmill speed, lactate measurements were taken after subjects had walked a distance of 400m. Recovery after exercise was evaluated after the third and sixth minutes of the 8-minute resting period. Furthermore, the heart rate was determined after every 100m of walking. The expired gas was measured to determine the following respiratory parametersd: oxygen consumption (V̇o2 [in mL/min], V̇o2/body weight [mL·min−1·kg−1]), carbon dioxide expiration (V̇co2 [in mL/min], V̇co2/body weight [in mL·min−1·kg−1]), ventilatory equivalent (in L/min), efficiency (in V̇o2·kg−1·m−1·s−1 per 60s), respiratory minute volume (L/min), and the respiratory quotient (in V̇co2/V̇o2).

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Results 

Fifty-two (85%) of the 61 patients (33 males, 19 females) reported that they were regularly involved in sports activities. Their ages ranged from 7 to 54 years (mean, 23.7±8.8y) and their mean follow-up after surgery was 6.7±4.6 years. Two men and 7 women did not participate in sports activities. Eight of the 52 patients participated in competitive sports. Fifteen patients were members of 1 sports club and 2 were in 2 sports clubs. Four patients were involved in swimming club, 3 in a soccer club, and 2 in a table tennis club. The others were involved in canoeing, dancing, basketball, judo, track and field, gymnastics, badminton, and horseback riding (fig 1).

Fifteen patients participated in 1 sport and 37 participated in more than 2 sports. Swimming was the sport that attracted most of the patients (n=24), followed by cycling (n=18), soccer (n=13), volleyball (n=10), and basketball (n=7). Some patients participated in sports that require a higher level of lower extremity coordination, such as in-line skating (n=3) and skiing (n=7). Racket sports, including badminton (n=11), tennis (n=7), and table tennis (n=8), were named often, while squash was not mentioned by any patient. More “exotic” sports like canoeing, ballet dancing, bowling, or cross-country motor biking (n=1) were rarely mentioned. It was encouraging that 1 patient with rotationplasty won the gold medal in the discus throw competition in the 1992 Paralympics, while another won fourth place in seated volleyball in the Athens Paralympics of 2004.

At the initial treadmill speed of .67m/s, the resting heart rate in the patient group was 93bpm, which was slightly higher than that of the control group (85bpm). After the first 100m the heart rate was significantly higher in the patients than in the controls (fig 2). The resting period was sufficient to allow heart rate recovery for both the patients (after 6min) and for the control group (after 3min).

  • View full-size image.
  • Fig 2. 

    Heart rate development at rest, at the slow treadmill speed of .67m/s (every 100m), and after 3 and 6 minutes of recovery; comparison of the patients and the control group. Abbreviation: E, recovery time. *P<.05; †P<.01; ‡P<.001.

At the intermediate treadmill speed of 1m/s, the initial heart rate after 8 minutes of rest was lower in both groups. Although the control group did not have an increased heart rate, as happened with the first speed level, the patients reacted with a higher heart rate (fig 3) that remained constant over the entire walking distance. The heart rate returned to the initial values during the resting period.

The measurements at the faster treadmill speed of 1.67m/s could only be completed for 7 patients. At that speed, the other patients felt insecure on the treadmill, notwithstanding that most of them were accustomed to higher walking and running speeds in the sports activities. In these patients, the heart rate increased steadily after the first 100m and reached values between 139 and 155bpm (fig 4). Heart rates in the control group reached a steady state level between 110 and 115bpm. The differences between the groups were significant at all measurements between 100 and 400m. After a 6-minute rest, the heart rate averaged 102bpm and was slightly higher than the initial values and the control group’s values

The initial lactate levels, as well as the recovery values, were higher in the control group than in the patient group. The lactate levels after exercise were higher in the patients at all 3 treadmill speeds, however. At the highest speed, the patients reached a blood lactate concentration of 2.51mmol/L, compared with the control group’s concentration of 0.82mmol/L (fig 5).

We analyzed both groups with respect to their respiratory functions. At all treadmill speed levels, the patients’ oxygen consumption and carbon dioxide expiration were significantly higher than in the control group (P<.001) (fig 6). The respiratory minute volume was not affected at .67m/s and 1.0m/s in the patient groups, but at 1.67m/s it almost doubled, from 23.5 to 46.3L/min (fig 7). It also increased in the control group, but was less pronounced (from 19.1 to 27.3L/min). The respiratory quotient revealed no marked differences at the 2 lower speeds (.67m/s, .83 vs .80; 1.0m/s, .81 vs .81). At the highest speed, the difference between the groups was significant (.92 vs .86, P<.05).

  • View full-size image.
  • Fig 7. 

    The respiratory volume per minute (AVM) was only slightly increased for the patients in the 2 lower treadmill speeds but was almost doubled in the highest treadmill speed as compared with the controls. All differences, however, were significant. *P<.01; †P<.001.

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Discussion 

The sports in which the rotationplasty patients participated were those commonly played in Germany. According to a 1996 public poll by the British-American Tobacco Institute of Leisure and Sports,23 41% of the general population participated in different levels of sports activities. Swimming was the most frequently mentioned activity (10%), followed by cycling (8%), soccer (7%), gymnastics (7%), and jogging (6%). Skiing (3%) and volleyball (1%) were less common. In our patient group, all activities were performed regularly and often, commonly through membership in sports, fitness, or health clubs. Sports activities that involve a high level of running (soccer, jogging) were engaged in by 25% of all patients. Racket sports were also played, with the exception of squash, which—due to the extreme acceleration and deceleration demands on the lower extremity—might simply be too demanding for the rotated foot being imbedded in the prosthesis. Seven patients regularly went alpine skiing, usually with mono skis and 2 skiing poles equipped with short skis. This percentage of active skiers in the patient group was higher than in the general population.23 In a long-term follow-up investigation after rotationplasty, Hanlon and Krajbich24 reported on the participation of patients in sports that were also mentioned by the patients in our study, as well as in sports such as field and ice hockey and water skiing; none of the patients in their study was inactive.

It is noteworthy that none of the patients in our study was involved in a special sports club for handicapped athletes, but were members in regular clubs. This is a sociologically interesting phenomenon because it indicates that the patients did not perceive themselves as being limited by the rotationplasty and therefore did not believe that they needed special training. This generally good outcome is associated with other observations about improved QOL and increased upright time in rotationplasty patients as compared with limb-salvage patients.7

There is little detailed information about athletic participation after lower-extremity tumor management. It is well established that patients with prostheses try to protect or save their prostheses because they fear they will sustain a fracture of the bone or the prosthesis.16 Eckardt et al,25 however, mentioned the possibility of participation in sports such as cycling, swimming, water skiing, and horseback riding after reconstruction of the proximal tibia with an endoprosthesis; such sports are less demanding on the lower extremity.

Our population of patients who had undergone rotationplasty showed a level of participation in sports activities that is comparable with, or even higher, than that of the general population.

The physiologic performance measures showed that the initial and the resting heart rates were similar in both the patients and the healthy subjects at all 3 speed levels. Therefore, there were statistically significant differences only during exercise after 100, 200, 300, and 400m. At a given speed, cardiorespiratory demand was higher in patients with rotationplasty than in the control group. Depending on the treadmill speed, the heart rate increased by 17 and 47bpm within the first 100m and remained constantly higher than in the control group. Alman et al26 described an increased heart rate of 13 to 64bpm at a maximal speed of 1.33m/s in a patient group with a lower average age (13.9y). The heart rates at the highest treadmill speed indicate that the patients did not reach their maximum cardiorespiratory limits. The heart rates of the participants in our study were closer to the aerobic steady state because none of the patients reached a close-to-maximum heart rate of approximately 180 to 200bpm (220 minus age).

At a treadmill speed of 1.67m/s the lactate levels of the patients were 3 times as high as in the control group. This lactate accumulation indicates a higher level of anaerobic energy production. According to Heck et al,27 the higher intracellular lactate and subsequent reduction of the pH values will ultimately lead to a reduced performance.

There have been few reports that have dealt with the sports, medical, or exercise physiologic evaluation after rotationplasty. Dating back to the 1970s, however, there have been reports about the influence of amputations on oxygen consumption. In below-knee amputees, the type of prosthetic shaft, as well as the amputation level, had an influence on energy consumption.18 Waters et al28 demonstrated that gait parameters and energy consumption were less affected in patients with lower resection levels. Griffith et al29 introduced a mobile unit with a velocity-controlled respirometer that he applied in a group of adults in 5 different velocities that were recommended for further reference measurement. Other authors used different velocities, which impairs the comparability of various investigations. Nowroozi et al22 investigated slow, medium, fast, and comfortable walking speeds in patients after hemipelvectomy and after hip disarticulation and compared them with speeds in a healthy control group. Patients with rotationplasty could walk or run at maximum speeds of 3.5 to 10km/h (average, 7.5km/h); a walking speed of 1.2 to 4km/h (average, 2.6km/h) was considered a comfortable pace. This was slightly slower than for below-knee amputees (3.6km/h).30 Knahr et al31 discussed a potential disadvantage because 5 of their patients were fitted with new prosthesis shafts and therefore were not yet fully accustomed to the new situation.

Sports prostheses with improved comfort and energy-storing foot parts can be customized to support the individual requirements for sports activities. Cummings et al,18 however, found no differences in the energy consumption of below-knee amputees with 2 types of prostheses that differed with respect to their weight, but they reported an influence of the fitness level.

Study Limitations 

We included patients with type A and type B rotationplasty in this study. A statistical comparison between groups was not possible, however, because of the smaller group of type B patients.

For type-BI patients (where the former knee joint is used as a new hip joint in case of a tumor in the proximal femur), Donati et al6 stated that gait analysis parameters and joint moments revealed patterns similar to the nonaffected limb, which would be a prerequisite for sports activities. It must be noted, however, that this “new hip joint” allows only flexion and extension movements and therefore limits physical activities and may cause higher loading of that joint. Results for the type-B patients, especially the subgroup type BIIIa rotationplasty, showed no functional differences in comparison with type A1 patients. Therefore, it can be stated that the type B rotationplasty results appear to be more beneficial than potential alternatives such as hip disarticulation or hemipelvectomy. According to our investigation, the gait velocity after hemipelvectomy or hip disarticulation was only 51% to 61% of the control group and the energy consumption was increased by 82% (hip disarticulation) or 125% (hemipelvectomy).

Previous reports about functional possibilities after rotationplasty were indicative but were usually based on smaller samples and comparisons with other subgroups of patients.14, 15, 16, 17, 18, 19 These former studies showed a trend of good functional results after rotationplasty, but did not provide clear evidence. Therefore, our report provides information about a larger group of subjects who were all treated in 1 center; it reinforces previous statements about higher oxygen consumption than that of healthy subjects, but lower consumption than that of other patients with amputations.15

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Conclusions 

Our results show that patients with rotationplasty walked with a higher cardiorespiratory demand but were not challenged to their individual limits at the 3 walking speeds. That a smaller number of patients performed the test at the highest walking speed was not because of physiologic limitations, but because of a subjective feeling of uncertainty on the treadmill. The experimental setup for the treadmill measurements limited the space for compensatory movements with the prosthetic limb, which the patients were usually using in everyday life or during sports activities for equilibrium adjustments. We conclude that patients after rotationplasty can re-engage in physical activity on a regular basis and that many do participate in a variety of sports activities.

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Acknowledgment 

We thank Joe Letkeman for proofreading the manuscript.

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References 

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  • a StatView 5.0l; SAS Institute Inc, 100 SAS Institute Dr, Cary, NC 27513.
  • b Woodway GmbH, Steinackerstr 20, 79576 Weil am Rhein, Germany.
  • c EBIO plus 666 lactate analyzer; EBIO, Barkhausenweg 1, 22339 Hamburg, Germany.
  • d Oxycon system; Jaeger Toennies, Viasys Healthcare GmbH, Leibnizstr 7, D97204 Hoechberg, Germany.

 Supported by the Deutsche Krebshilfe e.V. – Mildred-Scheel-Stiftung.No commercial party having a direct financial interest in the results of the research supporting this article has or will confer a benefit upon the author(s) or upon any organization with which the author(s) is/are associated.

PII: S0003-9993(07)00292-4

doi:10.1016/j.apmr.2007.04.004

Archives of Physical Medicine and Rehabilitation
Volume 88, Issue 7 , Pages 885-890, July 2007

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