Reviews
Clain and Baxter (1992) published a review in Foot and Ankle which gave an excellent overview of Achilles tendonopathy and introduced the classification into insertional and non-insertional tendonopathy.
Epidemiology
Most epidemiological studies relate to non-insertional tendonopathy in runners. Studies by Bovens (1979), Krissoff(1979) and Clement (1981) found an incidence of between 6 and 18%. Clement found Achilles problems to be twice as common in men.
Pathology
Tallon et al (2001) carried out microscopic studies on samples obtained from patients with rupture(35), tendonopathy(13) and normal tendons(16). The normal tendons were from older persons. A semiquantitative scoring system was used, which was fairly reliable. They found waviness and separation of collagen fibres with hyalinisation, increased rounding of cell nuclei, marked varibility in cellularity with cell proliferation, random blood vessel formation, decreased collagen stainabilityand increased glycosaminoglycan staining. These features were more marked in samples from ruptured than from painful tendons.
Ohberg et al (2001) performed grey-scale ultrasound and colour Doppler examination on 21 patients with chronic non-insertional Achilles tendonopathy and 14 controls. All the patients, but none of the controls, demonstrated neovascularisation of the thickened portion of the tendon, particularly in the ventral portion.
Alfredson et al (1999) demonstrated increased levels of glutamate, a neurotransmitter often associated with pain perception, in painful Achilles tendons compared with controls.
Tallon et al (2001) carried out microscopic studies on samples obtained from patients with rupture(35), tendonopathy(13) and normal tendons(16). The normal tendons were from older persons. A semiquantitative scoring system was used, which was fairly reliable. They found waviness and separation of collagen fibres with hyalinisation, increased rounding of cell nuclei, marked varibility in cellularity with cell proliferation, random blood vessel formation, decreased collagen stainabilityand increased glycosaminoglycan with 79 abnormal tendons (from a cohort of 76 patients/92 tendons),
Rufai et al (1995) described histological and pathological findings in the insertional region of the tendon. They used 50 cadaver tendons from 30 patients aged between 57 and 96. Normal tendons were attached to bone at an enthesis which contained a zone of fibrocartilage. Fibrocartilage lined the walls of most bursae. Pathological changes included bone spurs (16 specimens), which arose from the posteroinferior part of the insertion and contained traces of the calcified fibrocartilage present in the normal enthesis; longitudinal (19 specimens) and transverse (5 specimens) fissuring in the tendon; and degeneration of the bursal fibrocartilage (28 specimens).
Scott and Winter (1990) demonstrated forces in excess of six times body mass in the Achilles tendon during running. Subtalar movement and the spiral arrangement of the Achilles tendon fibres produce torsional forces in the tendon in addition. James et al () suggest that overpronation of the foot increases the stresses in the Achilles tendon and predisposes to tendonopathy; however, no data have been offered to support this. Indeed, Angermann and Hovgaard (1999) found that 14% of their patient were overpronators and 27% had cavovarus feet.
Natural history
Paavola et al (2000) reviewed 83 of 107 patients treated non-surgically for acute/subacute non-insertional Achilles tendonopathy with a variety of interventions. Follow-up was 8+/-2 years after the initial treatment; no information is given on independent review. 59% were asymptomatic at follow-up, 35% had mild exertional pain, 5% had severe pain on exercise and one had constant pain but continued to train. 84% had returned to their previous level of activity but one patient could not run and four could not walk. Muscle strength was equal on the initially involved and uninvolved sides. 42% of the involved tendons were tender and 22% had nodules. 29% had undergone surgery, mostly for tendon decompression. One patient had ruptured the tendon 3 weeks after the onset of symptoms. A small but not clearly specified number had developed insertional tendonopathy. 41% of the uninvolved tendons had becone painful, 29% were tender, 13% had nodules and 6% had been operated on.
It is interesting that, although ruptures only occur in degenerate tendons, rupture is rarely seen in populations of patients presenting with tendonopathy and pain. Tallon et al (2001)’s study on normal, painful and ruptured tendons found that tendonopathy samples showed twice as many degenerative changes, and ruptures three times as many, as controls.
Clinical features
The demographic features of patients vary quite widely from study to study. Some clinicians seem to see a younger, more physically active population than others. For example, Paavola et al’s patients with acute peritendinitis had a mean age of 32 years and only 2% did not play sports, while those of Mafi et al with chronic non-insertional tendonopathy had a mean age of 48 years and 43% did not play sports.
Investigation
Movin et al (1998) investigated 20 patients aged 27-79, who had had non-insertional tendonopathy for a mean of 12 (4-144) months. Each patient had ultrasonography (5-7mhz probe), contrast-enhanced MR (1.5T) and percutaneous biopsy. MR generally showed longer and higher-volume abnormalities than US, and was the preferred modality in 11 patients, although US was preferred in 3 and no preference in 6. Most abnormalities were medial and MR showed some asymptomatic insertional "abnormalities". Hypoechoic areas had a higher tendon pathology score and glycosaminoglycan/collagen ratio than noraml areas, although even the latter were raised.
Non-surgical management
Johnston et al (1997) described 41 patients treated with a mixed non-surgical programme. Mean previous duration of symptoms was 14 (6-60) weeks. 21 patients resolved after a mean of 18 (6-36) weeks’ treatment. There were no formal outcome measures and review was by the main treating doctor.
Angermann and Hovgaard (1999) reported 22 patients with peritendonitis for a mean of 5.4 (1-24) months. All were involved in sports. They were treated with heel raises, massage and an concentric exercise programme. 70% were improved at the end of treatment; at follow-up 33-72 months later, 13/20 were still improved. At follow-up, no patient had pain at rest, although increasing numbers had pain on higher levels of exercise, with 24% having pain on fast jogging. 13 patients were active in sports and the mean Tegner grade had increased from 6.6 before treatment to 8.8 at follow-up. One patient had had surgery for tendonopathy and two had had ruptures of the Achilles tendon.
Mafi et al randomised 22 patients with chronic non-insertional Achilles tendonopathy to eccentric and 22 to concentric exercises. Patients were reviewed 12 weeks after starting treatment; independent reviewers were not mentioned. 18/22 patients in the eccentric group compared with 8/22 in the concentric group were satisfied and resumed normal activities. Visual analogue pain scores improved more in the eccentric group and this was highly correlated with satisfaction and return to activity. No long-term results were presented.
Silbernagel et al (2001) randomised 49 patients with 69 painful Achilles tendons to eccentric or concentric exercises; 40 patients with 57 tendons completed the study. The evaluation protocol itself was assessed for reliability. The eccentric group were more likely to have no pain during or after activity, and to have returned to their previous level of activity. However, improvement in pain was similar, as was pain on walkin, stairs or jogging. The concentric group performed slightly better on physical testing. The test protocol was reproducible.
Surgery
Schepsis et al (1994) described 66 patients with 79 abnormal tendons (from a cohort of 76 patients/92 tendons), followed up a mean of 6.5(1-13) years after various tendon procedures. Mean age at surgery was 33 (17-59) years and 52 were runners. Mean duration of symptoms was 15 (5-40) months. 23 patients had paratendonitis, 15 tendinosis, 24 bursitis, 7 insertional disease and 10 mixed disease. The inflamed tendon sheath was excised. Abnormal tendon was excised through a longitudinal splitting incision. Two patients had local reinforcement procedures. Outcome was assessed non-independently, with nonspecific outcome measures. Excellent or good results were obtained in 20/23 with paratendinitis only, 10/15 with tendinodid, 18/24 with bursitis, 6/7 with insertional disease and 8/10 with combined disease. Tendinosis tended to recur 5-7 years after the original procedure.
McGarvey et al (2002) reported 21 patients (22 tendons) who underwent debridement of insertional tendonopathy through a posterior tendon-splitting approach. This is the only surgical series that concentrates on insertional tendonopathy. The mean age was 54 years (30-77); there were 8 men and 13 women. 21/22 had disease in the middle third of the tendon with lateral disease alone in only one. Three required reinsertion of the tendon with bone anchors and one reinforcement with plantaris, indicating over 50% resection. There were 2 patients with delayed wound healing, six with scar sensitivity or numbness and one superficial infection. They were reviewed at 26-40 months (mean 33 months) after surgery; the identity and independence of the examiner is not recorded. 13 had no pain at follow-up, 4 had reduced pain, 3 were unchanged and 2 worse. 13 were unrestricted in their activities, 3 could perform all desired activities but with some pain and 3 were restricted by pain. 18/22 were satisfied, though often with reservations; 17 would have the operation again. Patients under 50 recovered more quickly (90% versus 50% at work by 3 months), were more likely to be satisfied (90% versus 75%) and less likely to have residual pain (4.5% versus 36%).
Wilcox et al (2000) reported 20 patients who had Achilles tendon debridement and reconstruction with a FHL transfer, of whom 17 (19 tendons) had a diagnosis of tendonopathy and 3 chronic ruptures. Follow-up with examination, SF-36, AOFAS hindfoot score and Cybex testing was carried out 6-30 months after surgery (mean 14 months). No statement was made about independence of reviewer. Patients spent 8 weeks in cast and 4 in a brace. Mean AOFAS score was 86 (43-100) and 11 patients scored over 90. SF-36 scores were significantly lower than norms for physical functioning but normal otherwise. Cybex measurements showed a wide range, with a small mean loss of dorsiflexion strength and gain of plantarflexion strength; there was also a minimal mean loss of range of movement. 15 patients could do stand on tiptoe on the operated side. There were no wound problems, ruptures or tendonopathy recurrences.
References
- Alfredson H et al. In situ microdialysis in tendon tissue. Knee Surg Sports Traumatol Arthrosc 1999; 7:378-81
- Angermann P. Chronic Achilles tendinopathy in athletic individuals: results of nonsurgical treatment. Foot Ankle Int 1999 May;20(5):304-6
- Astrom M et al. Imaging in chronic Achilles tendonopathy. Skeletal Radiol 1996; 25:615-20
- Kolodziej P et al. Risk of avulsion of the Achilles tendon after partial excision for treatment of insertional tendonitis and Haglund's deformity: a biomechanical study. Foot Ankle Int 1999 Jul;20(7):433-7
- Kvist M. Achilles tendon injuries in athletes. Sports Med 1994; 18:173-201
- Mafi N et al. Superior short-term results with eccentric calf muscle training compared to concentric training in a randomised prospective multicenter study on patients with chronic Achilles tendinosis. Knee Surg Sports Traumatol Arthrosc 2001; 9:42-7
- Mathiak G et al. Serum cholesterol is elevated in patients with Achilles tendon ruptures. Arch Orthop Trauma Surg 1999;119(5-6):280-4
- McGarvey WC et al. Insertional Achilles tendinosis: surgical treatment through a central tendon splitting approach. FAI 2002; 23:19-25
- Morberg P et al. Long-term results after surgical management of partial Achilles tendon ruptures. Scand J Med Sci Sports 1997; 7:299-303
- Movin T et al. Tendon pathology in long-standing achillodynia. Acta Orthop Scand 1997; 68:170-5
- Myerson MS, McGarvey W. Disorders of the Insertion of the Achilles tendon and Achilles tendonitis. JBJS(A) 1998; 80A:1814-24
- Nelen G et al. Surgical treatment of chronic Achilles tendinitis. Am J Sports Med 1989; 17:754-9
- Niessen-Vertomen SL et al. The effect of eccentric versus concentric exercise in the management of Achilles tendonitis. Clin J Sports Med 1992; 2:109-13
- Ohberg L et al. Neovascularisation in Achilles tendons with painful tendinosis but not in normal tendons: an ultrasonographic investigattion. Knee Surg Sports Traumatol Arthrosc 2001; 9:233-8
- Paavola M et al. Long-term prognosis of patients with Achilles tendonopathy. Am J Sports Med 2000; 28:634-42
- Puddu G et al. A classification of Achilles tendon disease. Am J Sports Med 1976; 4:145-50
- Rufai A et al. Structure and histopathology of the insertional region of the human Achilles tendon. J Orthop Res 1995; 13:585-93
- Sammarco GJ, Taylor AL. Operative management of Haglund's deformity in the nonathlete. Foot Ankle Int 1998;19:724-9
- Schepsis AA et al. Surgical management of Achilles tendon overuse injuries. Am J Sports Med. 1994; 22:611-9
- Silbernagel KG et al Eccentric overload training for patients with chronic Achilles tendon pain. Scand J Med Sci Sports 2001; 11:197-206
- Stanish WD et al. Eccentric exercise in chronic tendinitis. CORR 1986; 208:65-8
- Stein V et al. Quantitative assessment of intravascular volume of the human Achilles tendon. Acta Orthop Scand 2000 Feb;71(1):60-3
- Tallon C et al. Ruptured Achilles tendons are significantly more degenerated than tendinopathic tendons. Med Sci Sports Exerc 2001; 33:1983-90
- van der Linden PD et al. Achilles tendinitis associated with fluoroquinolones. Br J Clin Pharmacol 1999 Sep;48(3):433-7
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