Table 2 shows our patients characteristics. 102 patients were treated for a number of 117 symptomatic heel spurs. 59 patients were treated with 60-cobalt therapy, 31 patients with orthovolt therapy and 12 patients with both radiation systems.
Table 2
Criteria
|
N° of patients
|
(%)
|
Patients
|
102
|
100
|
Female
|
74
|
71,8
|
Male
|
28
|
27,2
|
Spurs
|
117
|
100
|
Right-sided
|
55
|
54,1
|
Left-sided
|
32
|
31,6
|
Bilateral
|
15
|
14,3
|
Pre-treatment
|
134
|
100
|
Orthopedic insoles
|
48
|
35,8
|
Corticoid infiltrations
|
25
|
18,6
|
Antiphlogistics (oral)
|
34
|
25,3
|
Physiotherapy
|
3
|
2,2
|
Shockwave therapy
|
6
|
4,5
|
Massage
|
5
|
3,7
|
Ultrasound therapy
|
4
|
2,9
|
Antiphlogistics (ointment)
|
5
|
3,7
|
Corticosteroids (Oral)
|
2
|
1,5
|
Operative therapy
|
2
|
1,5
|
Prior to RT treatment, 100 patients (99%) presented with a Rowe S-Score between 0–30 (severe pain) and only 1 patient (1%) had a S-Score between 30–60 (mild pain) (Fig. 2).
On the last day of RT treatment, 21 patients (20.8%) achieved a S-Score between 0–30 (mild to no improvement), 26 patients (25.7%) a S-Score between 30–60 (mild pain improvement), 24 patients (23.7%) a S-Score between 60–90 (mild to moderate improvement) and 29 patients (28.7%) had a S-Score between 90–120 (good pain response). Only 1 patient (1%) achieved a complete pain response with a S-Score between 120–150.
If patients were contacted directly or interviewed by telephone and completed the questionnaire retrospectively for 6 weeks after radiation, during follow-up (at least 3 years after radiation treatment) 53 patients (52.5%) had a S-Score of 0–30 (mild to no improvement of pain), 2 patients (2%) a S-Score between 30 and 60 (mild improvement of pain), 7 patients (6.9%) a S-Score of 60–90 (mild to moderate improvement of pain) and 6 patients (5.9%) had an S-Score of 90–120 (major improvement of pain). Overall, 33 patients (32.7%) had a complete pain remission with a S-Score of 120–150.
At the time of data collection, the results of a telephone questionnaire were the following: 19 patients (18.8%) reported a S-Score of 0–30, 2 patients (2%) a S-Score between 60 and 90, 7 patients (6.9%) a S-Score of 90–120 and 73 patients (72.3%) had a S-Score of 120–150. No patient reported a S-Score of 60 − 40 and 14 patients (13.9%) expirienced a S-Score of 0.
As presented in Fig. 3 the best results were achieved 6 weeks after radiation therapy and if the radiation field was large.
Figure 4 shows the summary of the bootstrap confidence intervals of radiation results using the modified Rowe-Scores on the last day of RT, 6 weeks after RT and at data collection. Also, this investigation shows that the best results were achieved 6 weeks after RT.
The long-term response was evaluated in 102 patients after a median follow-up period of 94.4 months (range: 36–187 months). 16 patients received 2 irradiation series (4 patients received orthovoltage radiotherapy, 9 patients irradiation using cobalt and 3 patients both). Furthermore, the influence of different parameters (radiotherapeutic and clinical) on the therapeutic response (pain-reduction) of the irradiation of heel sporns was evaluated. There were no significant differences between the groups receiving different single doses at any time point (p-value: on the last day of RT: 0.922, 6 weeks after RT: 0.865, at data collection: 0.949). Similarly, no significant differences following the Pearson-correlation could be identified between the total dose (3 or 6 Gy) and the therapeutic results according to the Rowe-Scores on the last day of irradiation (r=-0.157, p = 0.172), 6 weeks after completion of radiotherapy (r = 0.013, p = 0.905) and at data collection (r=-0.061, p = 0.670). Moreover, no significant influence of the total treatment time on any outcome were detected using the Pearson-correlation: on the last day of radiotherapy (r = 0.06, p = 0.5), 6 weeks after irradiation (r = 0.022, p = 0.87) and at data collection (r=-0.12, p = 0.27).
Regarding the size of the radiation fields, there was a significant influence (p = 0.011, r=-0.0282) of the field size on the clinical outcome at 6 weeks after irradiation. This indicates a better effect of radiotherapy when an extended field was used, to irradiate the complete pain expansion on the heel. Nevertheless, this effect did not influence the early outcome on the last day of irradiation (r=-0.052, p = 0.657) and the late outcome at data collection (r=-0.036, p = 0.806). A pretreatment of patients with oral NSAIDs had a significant effect (p = 0.047) 6 weeks after completion of radiotherapy. While patients who did not receive NSAIDs (n = 23) had an average score of 65.22 (SD = 29.52), patients undergoing NSAID-therapy (n = 32) achieved an average Score of 51.25 (SD = 24.05). This indicates that pretreated patients who continued NSAID-therapy experienced a lesser pain-improvement than patients receiving radiotherapy without NSAIDs. This effect was not significant at long-term follow up.
Though not performed via randomization, we analyzed any effect of local steroid injection on therapeutic outcome. We identified a significant lapse of pain reduction when local corticosteroid-injection on the last day of radiotherapy was administered (p = 0.036). 31 patients without prior corticoid-therapy had an average score of 34.19 (SD = 16.6) compared to 24 patients who had received corticoid-injections reported an average score of 23.7 (SD = 20.6). This significant difference may indicate that patients receiving local infiltrations on the last day of radiotherapy experienced less pain reduction than patients without corticoid-therapy. It could also be that these patients have a more persistent heel spur and that there has been no improvement even after many pre-therapies. This significance was also observed 6 weeks after radiotherapy as well (p = 0.001), while it was not significantly different at long-term outcome (p > = 0.05).
There was no significant impact of the age of the patients on the therapy outcome on the last day of radiotherapy (r = 0.17, p = 0.12) and at long-term follow-up (r = 0.078, p = 0.49). Nevertheless, there was a significant influence of the patients’ age on the therapeutic results 6 weeks after radiotherapy (r = 0.28, p = 0.041). Higher age was significantly associated with improved outcome 6 weeks after irradiation.
Using the Mann-Whitney-U-Test, we were able to demonstrate that neither the patients’ gender, nor the technique used for radiotherapy did influence the outcome at any time. The symptomatic time before the beginning of radiotherapy showed a significant correlation on long-term outcome (p = 0.012, r = 0.315). Patients receiving irradiation a few months after the onset of heel spur pain benefited significantly more from radiotherapy and experienced a higher pain remission than patients with delayed irradiation.
In the present study, we have categorized pain into functional scores. The pain was subdivided into pain at rest, pain at motion and pressure pain. Overall, 33 patients (32.7%) reported a complete pain regression six weeks after RT. After a follow-up of 94.4 months (range: 36–187 months), 74 patients (73%) achieved a complete response. These results confirm the effectivity of this treatment approach. The analysis of functional scores revealed that 85.5% of the patients had none or only minor restrictions in daily activities and 89% had a normal gait pattern.