O.JARDE (1), P. DIEBOLD (2),

E. HAVET (1), G. BOULU (3), J. VERNOIS (1)

 

 

 

 

1 - Service d'Orthopédie-Traumatologie, Hôpital Nord - AMIENS,

2 – Clinique GENTILLY - MAXEVILLE

3 - Service de Radiologie B, Hôpital Nord – AMIENS,

O. JARDE, Ph D, is professor of orthopaedic surgery, CHU Nord, 80054 AMIENS, FRANCE.

 

Tel : 00 33 22 66 83 10. Fax : 00 33 22 66 85 80, jarde.olivier@chu-amiens.fr

 

Correspondence and reprints : O. JARDE, Ph D, CHU Nord, 80054 AMIENS. Place Victor Pauchet, 80054 AMIENS CEDEX 1, FRANCE.

 

Diebold Patrice MD is orthopaedic surgeon, clinique GENTILLY 54320 MAXEVILLE.

Havet Eric MD is orthopaedic surgeon, CHU Nord 80054 AMIENS FRANCE.

Boulu Gilles MD is radiographer, CHU Nord 80054 AMIENS FRANCE.

Vernois Joël MD is orthopaedic surgeon, CHU Nord 80054 AMIENS FRANCE.

 

 

From 1989 to 1999, 38 cases of degenerative lesions of the plantar aponeurosis were treated surgically. MRI revealed 8 cases of chronic aponeurositis and 30 old ruptures. Treatment was an aponeurectomy with resection of the heel spur after several months of conservative treatment. The histological examination found inflammation in all cases (aponeurositis or rupture), 4 cases of calcification of the aponeurosis, 4 cartilaginous metaplasia and 4 fibromatoses.

Patients were assessed after a minimum of 1 year and a maximum of 7 years. The post-operative results were assessed using 3 criteria: disappearance of pain, results on the static foot and patients' functional activity.

The overall score was: 24 very good and good results, 9 fair results and 5 bad results. The MRI performed at the time of follow-up revealed a good healing of the plantar aponeurosis in 16 cases, defects in 2 cases, inflammation in 7 cases and defects associated with inflammation in 13 cases.

Surgical treatment may be proposed when a conservative treatment of cases of talalgia has failed. Degenerative damage to the plantar aponeurosis, such as ruptures or aponeurositis, may benefit from an aponeurectomy. Short term results show pain disappearance in 75% of cases with a slight sagging of the plantar arch..

MRI enables us to explain precisely from where cases of talalgia originate. After the failure of conservative treatment, some cases of talalgia may benefit from an aponeurectomy.

 

 

INTRODUCTION

Talalgia is a frequently. Encountered complaint since its etiology is varied and diagnosis is often difficult, a certain number of treatment failures occur.

In 1975, Furey (9), in an analysis of 116 cases of chronic lesions of the plantar aponeurosis, noted that two of four cases that had undergone surgicical treatment, had made a complete recovery. In 1984, Lester and Buchanan (17) suggested surgery for ten patients, al though they were dealing with lesions of the fascia in patients who did not practise sports. Leach et al (15) in 1978, and then Snider et al (25) and Herrick (10) in 1983 described ruptures of the plantar aponeurosis in top-level sportsmen and women. In 1989, Poux et al (21) published a series of 30 cases of ruptures of the plantar aponeurosis, of which ten successfully under great surgical intervention. In 1993, Roger et al (22) demonstrated the value of Magnetic Resonance Imaging (MRI) for the diagnosis and treatment orientation of lesions of the plantar aponeurosis.

Pasternack and Davison (20) have stressed the value of MRI for the diagnosis of lesions of the muscular-ligamentous structures of the foot. The presents authors have, since 1989, performed MRIs to study the plantar aponeurosis in patients with talalgia and to select those patients for whom surgery would be viable.

Has performed a resection of the posterior third of the plantar aponeurosis in 48 feet, (Christel et al (5)), and we shall present here the 38 cases that have been followed up for a minimum of one year.

 

EQUIPMENT AND METHOD

- The Series :

Between 1989 and 1999, 38 feet in 12 men and 26 women were operated by the same surgeon as described below. Twenty right feet and 18 left feet were operated. Patients' ages ranged from 32 to 74 years, with an average age of 50 years. No patient was obese.

All of the patients suffered from talalgia, with localised pain at the anteromedial part of the calcaneus. In four cases pain had initially appeared during sports activities (in two cases running, in one case tennis, and in another soues football).

In thirty four cases (89%) pain progressively appeared about the calcaneal tuberosity, and was described as a burning sensation in 13 cases and an increasingly intense diffuse pain in 21 cases. These patients teported pain and stiffness in the morning. The pain decreased after a few steps and then became worse again during the day depending on the intensity of the activity.

In all cases, clinical examination of the plantar surface revealed abnormality. Palpation on the medial tubercle of the calcaneus produced acute pain in 38 patients.

Eighteen patients had a normal footprint, 6 had a stage 1 planovalgus foot, 2 a stage 2 flat foot with a centred hindfoot, 2 had stage 1 hollow valgus foot, 6 had a stage 1 hollow foot with a centred hindfoot and 4 had stage 1 hollow varus foot. Only one patient had a general decrease in foot mobility.

Standard radiological examination showed a heel spur in 30 cases (78,9%). In 8 cases there was no radiological anomaly of the large calcaneal tuberosity. The Djian-Annonier angle was between 110° and 120° in 12 cases (32%), between 120° and 130° in 18 cases (47%), and between 130° and 140° in 8 cases (21%). The average Djian-Annonier angle was 124°.

On average, all patients had been suffering from talalgia for 2 years before surgery. During that time all had had some form of medical treatment : insoles for at least three months (in 32 cases), one to three infiltrations (in 26 cases) or a general treatment with nonsteroidal anti-inflammatory medication (in 24 cases). The duration of previous medical treatment ranged from 4 to 24 months, and was on average 10 months.

An operative indication was made after well-managed medical treatment and leated on the results of MRI. Since 1989 all patients presenting with enthesopathy in the hindfoot have been Streted with MRI. Only 35% of those pathological MRI scans led to surgical intervention.

- MRI Investigation :

The examinations were performed using a high field system with a superconductor magnet of 1.5 Tesla (Sigma.).

A knee type surface coil was used, which gave us the potential for bilateral and comparative exploration.

After axial location, three sequences were performed in the sagittal plane, with a T1-weighted spin echo technique, a T2*-weighted gradient echo technique, and then, after intravenous injection of, Gadolinium. The sections were contiguous and 4mm in width. The length of the examination was 20 minutes. (fig 1.)

MRI findings made it possible to define two types of damage to the aponeurosis:

1 - Inflammation (aponeurositis) : the plantar aponeurosis was thickened. The thickening was poorly limited and sometimes accompanied by a partial disappearance of the aponeurotic hyposignal in the T1 sequence. Continuity was found, however, in the T2* sequence with a moderate hypersignal. After injection of Gadolinium, there was a contrast.

In our series there were 8 cases of aponeurositis, of which two had calcifications (fig 2).

2 - Disruptions of continuity. These combined an aponeurotic tear, close to the calcaneal insertion and limited thickening, which was usually fusiform and sometime lamellar.

In the T1 sequence, there was a loss of the aponeurotic hyposignal ; the disruption of continuity was clearly revealed in the T2* sequence and after injection of Gadolinium.

In the latter case, there was macked contrast where there had been a recent rupture. This may have disappeared when the rupture is old.

Thirty cases of disruption of continuity were diselosed : 14 centrally located aponeurotic ruptures (fig 3a), 16 tendinous detachments at the heel spur.

- Operative technique :

The approach was through a longitudinal medial incision, at the junction of the plantar and the dorsal skin, stopping behind the antero-posterior half of the calcaneus. After detaching the abductor hallucis on the medial side of the plantar aponeurosis, progressive dissection of the plantar surface of the aponeurosis from the aponeurotic tissue to the postero-medial tubercle of the calcaneus was made. The plantar aponeurosis was incised longitudinally along the lateral side of the abductor hallucis. The deep surface of the aponeurosis was freed by gradually detaching the fibres of the flexor digitorum brevis up to its insertion into the calcaneus. The muscle was drawn upwards and backwards by a retractor protecting the lateral plantar vascular-nervous bundle. The aponeurosis was then explored by palpation in order to locate the pathological area. It was then detached from the posteromedial tuberosity, along with the heel spur, and the pathological tissue was excised as required and following the MRI findings. Closure was achieved over an aspirative drain. Weight-bearing was allowed after healing after three weeks. The excised tissue was systematically sent to the pathology laboratory.

- Anatomopathology :

As Snider (25) has described, lesions found upon examination of the excised tissues could be divided into four stages :

- The first stage was that of collagen degeneration, with fibres losing their longitudinal arrangement and presenting a haphazard orientation, with an increase in the fibroblastic cellular density.

- The second stage was represented by pseudo-chondroid metaplasia with cells resembling chondrocytes situated within nodules which were dissociated by oedema.

- The third stage was that of an inflammatory granuloma with angiofibroblastic hyperplasia corresponding to an increase in vascularisation and to a local infiltration by cells from the inflammatory line.

The final stage was that of calcifications with patches of acidophilic necrosis in calcified areas.

These lesions were similar to those found in cases of epicondylitis, resulting from repeated microtrauma, which was responsible for the collagen degeneration. Healing did not occur because of the persisting microtrauma. None of our patients was operated on in the acute stage, which probably explains the existence of the chronic lesions we observed.

Pathological examination in our series found inflammatory lesions in all cases (aponeurositis or rupture), two cartilaginous metaplasias, two chondroid or osteoid metaplasias, four fibromatoses, two microcalcifications, two calcifications with associated cartilaginous metaplasia.

- Follow-up criteria :

The 38 patients were reviewed by the same examiner after a minimum of one year and a maximum of 7 years. The average follow-up time was 4 years.

At the time of follow-up all patients had an X-ray and an MRI scan taken of the relevant foot.

The post-operative results were assessed according to 3 criteria of KITAOKA (13) :

- the disappearance of pain,

- the statics of the foot.

- the patients functional activity. This was assessed based upon the ability to wear shoes, the distance the patient could walk before experiencing pain, and his/her home activity.

The scores that were obtained (table I) were added up in order to produce an overall result described as very good, good, fair or bad.

They were assessed according to the following :

- the disappearance or persistence of pain. Very good results gave total disappearance of pain, whereas good results had a persistence of weather pain,

- the results on the statics of the foot (whether modified or not),

- the patients' functional activity according to the ability to wear shoes, the normal or limited distance they could walk before experiencing muscle pain, and their home activity.

RESULTS

A – Complications :

Four cases of delages around healing (up to three months) were observed.

B - Results after more than one year :

The average recovery time was two months, with a sange forme one to three months. In 26 cases, pain when standing upright had disappeared (69%), in two cases the pain was rated as mied (5%), in 8 cases pain limited the activity (21%), and in two cases the pain was permanent and prevented all activity (5%).

The ability to wear shoes was normal in 28 cases (73.7%). Comfortable footwear was necessary in 10 cases (26.3%). No patient needed slippers, nor specially adapted footwear. Podiatric examination revealed :

- in five cases an unchanged footprint, of which :

            - 3 retained a normal footprint.

            - 2 retained a stage 1 flat foot.

- in 32 cases a changed footprint :

            - in 10 cases a normal footprint had changed to show slight sagging of the plantar arch, without reaching stage 1 flat foot.

            - in 5 cases a normal footprint changed to a stage 1 flat foot.

            - in 6 cases a stage 1 flat foot had changed to a stage 2 flat foot.

            - in 12 cases a stage 1 hollow foot had changed to show a normal footprint.

In 28 cases the distance patients could walk before the occurrence of muscle pain was normal. In 10 cases this distance was slightly limited, and in two of these cases it was limited to less than half of the normal distance.

4 patients had healing that was both painful and of bad quality.

Patients were absent from work for a time period ranging from 3 weeks to 8 months. The average time off work was 4 months. Three occupational modifications were noted : in one case a patient was able to work at a desk, in 2 cases patients were able to reduce the distance they were required to walk.

- Overall results :

We noted 10 very good results, 14 good results, 9 fair results and 5 poor results.

- X-ray and MRI results

X-rays showed no regrowth of the heel spur.

A slight modification of the Djian-Annonier angle was observed. After surgery it was 130°. Therefore, the average sagging after total aponeurectomy was 6°.

MRI scans showed good quality healing of the plantar aponeurosis in only 7 cases. Int the other cases, it showed :

- an almost complete reconstitution of the plantar aponeurosis with clear evidence of a slight contrast around the insertion, indicating the persistence of an inflammatory process in two cases (6%).

- an aponeurotic reconstitution around the insertion, with considerable aponeurotic thickening - probably occuring as an after-effect - in 7 cases (18%).

- no reconstitution of the plantar aponeurosis with a slight contrast at the insertion in 6 cases (16%).

- a disappearence of the plantar aponeurosis without any visible focal contrast could suggest an inflammatory process of the area having undergone surgery in 7 cases (18%).

- continuity of the plantar aponeurosis in 7 cases (18%), of which two with a slight contrast indicating persistent inflammatory phenomena.

- a slight aponeurotic defect over a few millimetres in the area having undergone surgery in 2 cases (6%).

DISCUSSION

Like Christel et al (5), we think that the heel spur must no longer be considered as the cause of pain but as both an indicative of a problem affecting the plantar aponeurosis, and the sign of an existing enthesopathy. The constant presence in our series accords with this view. Unlike in Christel et al’s series (5), our were masney mature subjects (the average age was 50 years) who had a degenerative lesion causing talalgia. There were only four young subjects, each of whom practised a sport and for whom the lesion was a side-effect of the regular practice of that sport.

Froman and Green (8) have suggested that the formation of the spur is due to the compensatory role played by the intrinsic foot muscles in stabilising the foot during abnormal pronation. The abductor hallucis and the flexor digitorum brevis, which partially originate from the plantar aponeurosis, are placed under great tension as they try to stabilise the hypermobile foot. This tension brings about periostitis and then the formation of a spur at the insertion of the plantar aponeurosis into the medial tuberosity of the calcaneus. It appears that in the case of the hypermobile foot both the plantar aponeurosis and the intrinsic muscles play a part in the development of plantar aponeurositis.

By showing the type of aponeurotic lesion, MRI enabled us to select the optimal treatment. In the absence of any objective indication of the plantar aponeurosis being affected, conservative treatment is advised. However, the distinction between aponeurositis and rupture of the plantar aponeurosis has not altered our surgical standpoint. Unlike Roger et al (22), we have not noted that the level of damage (medial or lateral) to the plantar aponeurosis is, on the whole, harmful.

This series and pathological investigation seem to show that enthesopathies of the plantar aponeurosis do indeed exist.

Zingas et al (28), have studied the histopathological changes of the plantar aponeurosis in 48 cases of common talalgia. They found degenerative changer in all specimen. In 12% of cases there was infiltration of the aponeurosis with inflammatory cells. There was damage to muscle groups through continuity. They found no difference between patients who had had infiltrations and those who had not.

These authors advised a medial approach. The plantar approach must be avoided because of painful after-effects.

As Sarrafian has said (24), surgical excision of the plantar aponeurosis modifies the static plantar arch. Like Salathe and Arannio (23), we have wondered about the responsability of the plantar aponeurosis in the maintenance of the arch. In fact, the deepest elements, such as the calcaneo-cuboid ligament, are, by themselves, capable of ensuring the maintenance of the architecture of the foot, as Poux et al (21) have shown through both cadaver dissections and podometric and radiological observations on patients having undergone surgery.

Like Kwong et al (14), we think that a tendency towards flat foot is often associated with a lesion of the plantar aponeurosis because the arch is crushed, causing persistent tension on the aponeurosis. Moreover, 8 of our patients had a flat foot. The hollow foot is relatively rigid, and poorly adapted to the accumulation of impact stresses from running. Moreover, a hollow foot was found 12 times in our series. The superficial plantar aponeurosis is compared by Kwong et al (14) to the string of a bow where tension is increased in the hollow foot.

For Lutter (18), by maintaining the heel for too long in forced supination, the hollow foot prevents the local cushioning provided by the bursa, the curve of the calcaneus and the ligamentous structures of the midfoot. Likewise, the shortening of the Achilles-ankle-plantar system leads to continuous traction on the calcaneal insertion of the superficial plantar aponeurosis.

The role of infiltrations may also be raised as contributing factor for ruptures of the plantar aponeurosis. Balasubramaniam and Prathap (3) have demonstrated, in experiments on the Achilles' tension of rabbits, that a local injection of corticoid causes localised necrosis of collagen tissue and predisposes to rupture of the tendon or fascia. There were infiltrations in 26 of our patients. Leach et al (16) concluded that injections into the plantar aponeurosis must be avoided.

The pain associated with rupture of the plantar aponeurosis is acute, whilst that involved in musculo-aponeurositis is more progressive, more fasciitis profound, and more insidious in the way in which it appears.

Anderson and Foster (2), in their article on surgical treatments for heel spurs, quota five different authors (Ali [1]; McBryde [19]; Snider et al [25]; Tanz [26]; Ward and Clippinger [27]) having performed a total of 63 plantar aponeurectomies without removal of the spur. Of these 61 are rated as excellent or good results, but the follow-up is less than 10 years.

Kenzora (11) emphasizes the number of post-operative neuromas (15 patients out of 27). These neuromas, all painful and difficult to treat, are due to an inadequate approach to, and dissection of, the posterior elements. The use of mini-incision surgery to try to "rip out" the heel spur seems to be the worst therapeutic solution.

Contompasis (6) has produced a three-year retrospective study of 126 cases of surgery for plantar aponeurositis. In 115 cases freeing of the plantar aponeurosis was performed with removal of the heel spur, whereas in 11 cases, the heel spur was left intouched. The two procedures produced excellent results, but follow-up was only three years.

Surgical treatment is indicaded in cases where conservative treatment has failed. For Poux et al (21), an old rupture that remains painful after two to three months of well-managed conservative treatment is an indication for surgery. Our results are clearly worse than those in his series as, he reported good results for the 10 patients having undergone surgery with a follow-up time of 26 months. However, the subjects are different, because Poux et al's series (21) is composed only of young subjects having had a traumatic rupture. On the contrary, our series shows degenerative lesions in mature patients with an average of 50 years. Thirty of these lesions developped after a rupture.

Lester and Buchanan (17) recommend simple disinsertion of the plantar aponeurosis. We prefer freeing the plantar aponeurosis with excision of the abnormal areas in order to remove the scar tissue witch may be at the origin of the pain.

Open surgery is not without complication. There are problems with post-operative healing, pain caused by the wearing of shoes, and neuromas.

For these reasons, Barrett et al (4), in 1991, suggested that the aponeurectomy should be carried out endoscopically. At first, this was performed with just one medial approach. Subsequently, the authors have opted for a technique using two approaches. This allows for a better view of the medial anatomy with less damage to the tissue than in the original technique. Some studies have shower that endoscopic plantar aponeurectomy is associated with less post-operative morbidity and has better functional results, a shorter recovery time and a more rapid return to normal activity than is the case for open surgery. The series are still too recent to evaluate sagging of the plantar arch after endoscopic intervention.

Aponeurectomy allows for better regrowth of the aponeurosis. There is, therefore, less risk of recurrence. This is an area which, with the aid of endoscopy (allowing only aponeurectomy), is still open to study. According to Kinley et al (12), the ideal instruments of the future would be double cannulas that would allow for partial removal of a portion of the plantar aponeurosis, and thus reduce the recurrence rate.

The surgical indications and courtable-indications of endoscopic plantar aponeurectomy are the same as for traditional surgery. However, this surgical technique is recommended by the authors for suitable patients. Patients must be informed about the etiology of the syndrome and of the relative insignificance of the heel spur. Patients who are unable to understand this message should preferably undergo traditional surgery with exostosectomy.

Endoscopic plantar aponeurectomy is a very precise technique, which, in the authors' opinion, must not be attempted without training.

The use of endoscopy is still new. Many aspects of this type of surgery need to be refined once more detailed functional and biomechanical studies have been completed.

However Davies et al (7) assert the mainstay of treatment for plantar fasciitis remains nonoperative. In the small percentage of patients who fail to nonoperative treatment over a period of at least 12 months, surgical treatment should be considered. It is essential however, that patients be warned of the potential benefits ansdlimitations of surgery. The operation should be seen as a last resort treatment, if regarded as such, it has an acceptable such rate.

Fig. 1: Normal MRI of the plantar aponeurosis.

 

Fig. 2: Musculo-aponeurositis with enthesopathy on T2.

 

Fig. 3: A - Rupture of the middle third of the plantar aponeurosis on T2.

            B - Enthesopathy with disinsertion of the plantar aponeurosis on T2.

 

Fig. 4: A - Post-operative MRI showing continuity of the aponeurosis with, however, a modification of the signal and a slight contrast indicating persistent inflammatory phenomena.

 

            B - Post-operative MRI showing a small defect of a few millimetres, located 0.5cm from the calcaneal insertion.

 

 

SCORE	PAIN	STATIC FOOT	FUNCTIONAL ACTIVITY
			FOOTWEAR	Distance walking before pain
0	Permanent, prevents all activity	Secondary flat foot	Slipper	Limited to home environment
1	Limits	Slight sagging of the plantar arch	Adapted footwear	Less than half of the normal distance
2	Meteorological	Very light modification	Standard footwear	Equal to or more than the normal distance
3	None	Unchanged	Normal	Normal

 

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