Comparison of Three Types of Postoperative Management for Endoscopic Plantar Fasciotomy A Retrospective Study

Abstract

This study compared three types of postoperative management of patients undergoing endoscopic plantar fasciotomy. Participating in the study were 38 patients (45 feet) who had undergone endoscopic plantar fasciotomy from 1995 to 1998. One group of patients wore a below-theknee walking cast with a molded medial longitudinal arch for 2 weeks; another group was allowed immediate plantigrade weightbearing; the third group was nonweightbearing with crutch-assisted ambulation for 2 weeks. The results showed that the patients who wore the below-theknee walking cast for 2 weeks required less time to obtain 80% pain relief, needed less time to return to full activities, and had fewer complications than those patients who were allowed immediate plantigrade weightbearing. Moreover, patients who wore the below-the-knee walking cast were more satisfied with their postoperative results than patients who were nonweightbearing for 2 weeks.

Plantar fasciitis is heel pain caused by inflammation of the plantar fascia where it inserts at the medial calcaneal tuberosity. The plantar fascia is a sheet of fibrous tissue that supports the longitudinal arch of the foot. Kinley et al [1] theorized that inflammation occurs at the medial calcaneal tuberosity when the fascia is strained by either excessive pronation or a rigid pes cavus foot that prevents normal pronation. A spur protruding from the plantar calcaneal tuberosity in an anterior direction is sometimes associated with this condition and may be seen on a lateral radiograph of the foot. This spur is thought to be due to traction from tight muscles or ligaments inserting into the calcaneus. It has been shown that plantar fasciotomy alone, leaving the spur intact, is an effective treatment for heel pain associated with plantar fasciitis [2,3,4].

Conservative therapy is effective for about 70% to 90% of patients with plantar fasciitis [2]. Conservative treatment methods include taping, padding, stretching, rest, application of ice, corticosteroid injections, heel cups, orthotic devices, nonsteroidal anti-inflammatory drugs, hydrotherapy, ultrasound, night splints, and below-the-knee casts.

Surgical treatment is usually employed after a 6-month course of conservative therapy has failed to provide adequate relief of pain. Surgical treatment is not always 100% successful. A variety of surgical procedures have therefore been developed, including radiofrequency lesioning of the plantar fascia [5], midfoot plantar fasciotomy, calcaneal rotational osteotomy, surgical decompression or neurectomy of the medial calcaneal nerve (Baxter’s nerve) [6,7], open plantar fasciotomy with heel spur resection, and endoscopic plantar fasciotomy [2,8,9]. The last two procedures have probably been the most widely used and debated procedures described in the literature of the 1990s [1,8,10,11].

Barrett et al [12] introduced the endoscopic plantar fasciotomy in 1991. Barrett et al [12] and Stone and Davies [13] argued that this procedure was superior to the open technique because it minimized surgical trauma, thus resulting in a higher success rate and faster return to full activities. Although the procedure has been used successfully, it has not been free of complications [14]. Among these complications are infection, continuation or return of heel pain, metatarsal stress fractures [15], ball and toe pain, reflex sympathetic dystrophy, fatigue and stiffness of the arch, painful scarring, numbness, tract pain caused by the endoscopic cannula beneath the plantar fascia, traumatic pseudoaneurysm of the lateral plantar artery [16], and lateral column or cuboid pain, which is the most common complication [13]. With this last complication in mind, modifications have been recommended since the introduction of the original procedure by Barrett et al [12], which released the entire plantar fascia by means of a two-portal technique and allowed the patient to bear weight in a shoe postoperatively. Stone and Davies [13] suggested that only the medial half of the plantar fascia be released and that patients wear a short-leg cast for 4 to 6 weeks postoperatively to avoid biomechanical complications and to increase patient satisfaction. In a recent study, Stone and McClure [17] concluded that consistent use of these modifications would probably yield better postoperative results.

Building on the work of Stone and McClure [17], the authors undertook the current study to determine which course of postoperative management following endoscopic plantar fasciotomy was most effective in reducing pain, provided the fastest recovery time, was associated with the fewest complications, and resulted in the greatest patient satisfaction. The authors compared three types of postoperative management: one group of patients wore a weightbearing below-the-knee cast with a molded arch for 2 weeks following surgery, another group was allowed immediate plantigrade weightbearing, and a third group was nonweightbearing without a cast for 2 weeks.

Subjects and Methods

A retrospective study was performed of 38 patients (45 feet) who had undergone endoscopic plantar fasciotomy from 1995 to 1998 to correct plantar fasciitis. Surgery was performed on 17 right and 28 left feet. There were 9 male and 29 female patients. The average age of patients in the three groups was 45.3 years for the below-the-knee cast group, 43.0 years for the weightbearing group, and 44.0 years for the nonweightbearing group. The average weight and height were 196.5 pounds and 66 inches, 207.6 pounds and 67 inches, and 168.2 pounds and 65 inches for the below-the-knee cast, weightbearing, and nonweightbearing groups, respectively. All patients had received at least 6 months of some form of conservative treatment before surgery, including taping, padding, orthotic devices, steroid injections, ultrasound, heel cups, application of ice, rest, stretching, nonsteroidal anti-inflammatory drugs, night splints, and hydrotherapy. Four different surgeons performed the procedures (M.D.C., M.D.C., J.W.L., K.A.S.). The surgical technique performed on all patients was the same as that described by Barrett [11] and Barrett and Day² except that the lateral third of the plantar fascia was left intact.

Patients in the first group (15 feet) were placed in below-the-knee fiberglass casts with a molded medial longitudinal arch (made while the cast was still wet and pliable), with the ankle at 90°, for 2 weeks. These patients were allowed to bear weight. After 2 weeks, the cast was removed and the patients were allowed to bear weight as tolerated with regular footwear and orthotic devices. A second group of patients (15 feet) was allowed to walk as tolerated with a surgical shoe on the day of surgery. The patients were allowed to wear regular footwear with orthotic devices a few days after surgery. The last group of patients (15 feet) was instructed to remain nonweightbearing with crutch- or walker-assisted ambulation for 2 weeks. At the end of this period, the patients were allowed to walk as tolerated in regular footwear and orthotic devices.

The patient charts were not evaluated until at least 6 months postoperatively. The charts were examined for age, sex, weight, height, duration of preoperative pain, extent and type of conservative treatment, and complications. The following were considered complications: continued heel pain for more than 6 months, return of heel pain, lesser metatarsalgia, stress fracture of lesser metatarsals, peroneal tendinitis, lateral column pain, tract pain, and a painful scar. All patients were contacted by telephone at least 6 months following surgery and asked questions about their preoperative period and postoperative recovery period. A satisfaction scale was incorporated into the questionnaire, based on a visual analog scale of 0 to 10 as modified from Leventeen and Pearson [18]. A score of 0 represented total dissatisfaction with the surgery; a 10 represented complete satisfaction, with 100% pain relief and no complications. The patients who wore the below-the-knee cast were asked if they had any pain during the first 2 weeks after surgery and whether they would wear the cast again if given the choice. The patients who were nonweightbearing with crutches were asked if they would use crutches again or, if given the choice, would choose a belowthe-knee walking cast. A statistical chi-square analysis with a 95% coefficient was performed to compare the data gathered from the questions asked of the patients.

Results

Before surgery, patients were able to be on their feet before developing pain an average of 4.3, 2.9, and 3.7 hours per day in the below-the-knee cast, weightbearing, and nonweightbearing groups, respectively (

Table 1. Mean Data for the Three Patient Groups.

). More than 6 months after surgery, patients in the three groups were able to be on their feet or were able to work for an average of 8.3, 8.1, and 7.6 hours, respectively. The average number of weeks until the patients experienced 80% pain relief was 4.8 for the below-the-knee cast group, 15.2 for the weightbearing group, and 10.6 for the nonweightbearing group. The difference between the belowthe-knee cast group and the weightbearing group in time needed to obtain 80% pain relief was statistically significant (χ² = 7.76), with eight feet in the former group taking 3 weeks or less to obtain relief, as compared with one foot in the latter group. The belowthe-knee cast, weightbearing, and nonweightbearing groups took an average of 10.2, 23.2, and 17.9 weeks, respectively, to return to full activities. The difference between the weightbearing group and the below-theknee cast group in time needed to return to full activities was statistically significant (χ² = 6.4), with three feet in the former group requiring 8 weeks or less, as compared with ten feet in the latter group. The belowthe-knee cast group had only two complications, significantly fewer (χ² = 7.0) than the weightbearing group, which had nine complications, and the nonweightbearing group, which had six complications.

The average satisfaction score and the number of patients with a satisfaction score of 9 or higher, respectively, were 9.2 and 11 for the below-the-knee cast group, 7.3 and 7 for the weightbearing group, and 7.6 and 5 for the nonweightbearing group. The difference in satisfaction levels between the belowthe-knee cast group and the nonweightbearing group was statistically significant (χ² = 4.84). All of the patients who wore the below-the-knee walking cast for 2 weeks after surgery stated that they were completely pain-free during this time and that they would elect to wear the cast again if the surgery were repeated. Only 5 of 13 patients in the nonweightbearing group at 2 weeks postoperatively said that they would use crutches or a walker again if given the choice between these devices and a below-the-knee walking cast.

Discussion

The average age of patients in all three groups studied was very similar, with no more than a 2-year difference between any two groups. Higher weight and short stature were not necessarily associated with a slower recovery period, more complications, or poor patient satisfaction in any of the three groups. Some of the short and obese patients had fewer complications than the tall and nonobese patients. These findings are consistent with results of Kinley et al [1], who found no correlation between obesity and time before relief of pain.

The average number of hours that patients could be on their feet before developing pain preoperatively was very similar in all three groups: the average time was between 2.9 and 4.3 hours, indicating that no one group had especially pronounced pain relative to the other two groups. Kinley et al [1] found that a duration of heel pain of less than 6 months was associated with a shorter recovery time. To avoid patients’ having a shorter recovery time as a result of a short duration of preoperative heel pain, all patients in the study had suffered from heel pain for at least 6 months before surgery. The average number of hours that patients were able to be on their feet or were able to work per day before developing heel pain at least 6 months postoperatively was approximately 8 hours for all three groups. The initial 2-week postoperative course did not seem to affect the outcome after the 6-month period, probably because all three groups were walking in regular footwear with orthotic devices after a few weeks.

There were statistically significant differences among the three groups in number of weeks until 80% pain relief following surgery. The group that wore the below-the-knee cast for 2 weeks following surgery obtained 80% pain relief three times as fast as the weightbearing group and twice as fast as the nonweightbearing group. A possible explanation for this is that the molded arch of the cast prevented reattachment of the plantar fascia in a contracted state by continually stretching it and keeping the foot out of an equinus position for 2 weeks. Also, the cast may have helped off-load the heel, so that surgically traumatized tissue did not scar, resulting in less pain postoperatively [19,20].

The below-the-knee cast group was able to return to full activities following surgery almost twice as fast as the other two groups. This fact is attributed to the patients needing less time to obtain 80% pain relief and having fewer complications following surgery.

There were four times more complications in the weightbearing group and three times more complications in the nonweightbearing group than in the below-the-knee cast group. The high complication rate in the weightbearing group is probably due to the fact that those patients were walking on unsupported, traumatized tissue. Because these patients have more heel pain, they are probably trying to offload their heels, thus altering their foot biomechanics and placing stress on other structures.

The most common complication was lateral column pain or peroneal tendinitis in the weightbearing group. This is consistent with the findings of Barrett et al [21] in their study of 652 cases of endoscopic plantar fasciotomy. The nonweightbearing group had a 40% complication rate, with the most frequent complications being return of heel pain and a painful scar. This finding is probably due to the patient’s hanging the foot in an equinus position for 2 weeks, thus allowing the plantar fascia to reattach in a contracted state [20]. Two complications occurred in the weightbearing cast group. Tract pain was found in one patient who had had bilateral endoscopic plantar fasciotomies within 6 months of each other; the tract pain occurred after the second procedure. This complication was probably due to the patient’s trying to rush her recovery period after the second procedure because she had recovered so quickly after the first. The other complication was lesser metatarsalgia in an obese female patient who was 63 inches tall and weighed 202 pounds. She stated that she walked on the ball of her foot because she developed some heel pain after removal of her cast. Both patients who had complications did recover fully following a steroid injection and insertion of some accommodative padding in footwear.

The below-the-knee cast group tended to be more satisfied than the other two groups with their postoperative treatment course and outcome. This may be attributed to the patients obtaining 80% relief of heel pain within a shorter amount of time, a faster return to full activities, and a lower incidence of complications.

The findings of this study were very similar to those in the recent study by Stone and McClure [17]. However, this study differed in that all patients compared had at least the lateral third of the plantar fascia intact following their endoscopic plantar fasciotomy, whereas the Stone and McClure [17] study included a comparison of results with those of a previous study by Stone and Davies [13] that included patients who had the entire plantar fascia released. Because it has been found that not releasing all of the plantar fascia reduces biomechanical complications [22], it is difficult to believe that the below-the-knee walking cast that was used postoperatively was the major reason for the better results in the study by Stone and McClure [17].

Another difference with this study was that the short-leg walking cast that was applied had a molded arch and was worn for only 2 weeks, which resulted in a faster return to full activities: the time to return to full activities in this group was 10.2 weeks, as compared with 13.5 weeks for patients in the study of Stone and McClure [17]. The difference is probably due to the molded arch, which helps support the reattachment of the plantar fascia in a contracted state. Evidence for this theory is provided by the lack of complications involving return of heel pain or fatigue and stiffness in the arch.

Even though this study demonstrated that patients wearing a below-the-knee walking cast for 2 weeks following endoscopic plantar fasciotomy did better postoperatively during the first 6 months, the study does have certain shortcomings. First, this is a preliminary study involving only 45 feet; therefore, a much larger patient sample is needed. Also, because this study is a retrospective study, patients may have had trouble recalling exact time frames and postoperative complications. A prospective study is needed to evaluate and question patients during specific time periods following surgery.

Conclusion

This retrospective study found that patients who wore a below-the-knee walking cast for 2 weeks following surgery took less time to obtain 80% pain relief, needed less time to return to full activities, and had fewer complications than patients who were allowed plantigrade weightbearing immediately after surgery. Furthermore, patients who wore a belowthe-knee walking cast were more satisfied than patients who were nonweightbearing for 2 weeks. Thus the authors recommend that patients who undergo endoscopic plantar fasciotomy wear a below-theknee walking cast with a molded arch for 2 weeks following surgery.