Patients who have persistent pain and disability after adequate non-surgical treatment may be offered surgical debridement of the tendon. We would not normally offer surgery for persistent swelling of the tendon as this is not usually a problem in itself.
Most surgical series describe debridement for non-insertional tendonopathy. Others focus on excision of paratenon for peritendonitis, usually in athletes. However, many include some patients with insertional tendonopathy and pathologies are often mixed in the same series.
Outcome measures tend to be vague, although with the introduction of the validated VISA-A score this is improving.
The extent of debridement varies from paper to paper. Some excise most abnormal tissue; others simply remove the worst sections, or only remove thickened paratenon, leaving tendon abnormalities alone.
At one extreme, some authors do not remove abnormal tendon at all, but simply incise it expecting this will encourage vascular ingrowth and healing. Testa (2002) described a percutaneous, ultrasound guided technique of incision, under local anaesthetic. 47/63 (75%) obtained excellent or good results and over half the others underwent open surgery.
At the other extreme is Martin's (2005) technique of total excision of the diseased segment and FHL grafting. Three years post-operatively in 44 patients, SF-36 scores were US norms and mean AOFAS in a subgroup who were re-examined was 91.6/100, although the mean strength deficit was 30%.
Probably the most informative series is that of Schepsis (1994). This included 73 procedures with very little loss to follow-up at a mean of 6.5 years. However, the pathology was mixed. Thickened paratenon was excised and abnormal tendon excised conservatively. Outcome measures were non-specific. Excellent or good results were obtained in 87% with peritendonitis and 67% with tendonopathy. Tendonopathy tended to recur 5-7 years after the original operation - it is important to tell patients this.
Vulpiani (2003) reported 76 patients at a mean of 13 years after surgery. Once again this was a heterogenous group, with 50/52 patients having little or no pain and back to the previous levels of sport after surgery for paratendonitis, non-insertional tendonopathy or mixed insertiona/non-insertional tendonopathy; only pure insertional tendonopathy did less well, with 26/34 achieving such results.
Nelen (1989) described 93 tendons with paratendonitis who had release of the paratenon and fascia, and 50 with tendonopathy who had resection of the abnormal tendon and simple suture (26 tendons) or flap reinforcement (24 tendons). Seventy-nine other patients were lost to follow-up, making it difficult to draw conclusions. Excellent or good results were obtained in 88% of paratendonitis and 80% of tendonopathy.
Vega (2008) described endoscopic debridement and longitudinal incision of the Achilles tendon in 8 patients. At 27 months' follow-up, all were pain-free and had returned to their previous sports. Vega worked from the subcutaneous surgface of the tendon, while Thermann (2009) worked from the deep surface as this is closer to the neovascularisation. Thermann's series also consisted of 8 patients followed for 6 months. Mean VAS pain score improved from 40-97.5/100 and VAS function score from 22.5-90/100. There were no infections or nerve injuries. Endoscopic debridement needs to be further defined in larger series.
An alternative method was described by Costa (2006). 21 patients with non-insertional tendonopathy had open Achilles tendon lengthenings of 1cm, followed up for 1-16 years. No tendon resection was done. Post-operatively patients wore a BKW cast for 6 weeks. Results are not very clearly presented, but visual analogue pain score improved by a median of 20/100 for rest pain, 40/100 for walking pain and 50/100 for running pain (all significant). The Euroquol generic health score also improved significantly. The operated ankles had a mean of 5deg extra dorsiflexion, but this did not affect any measured gait parameters. There was one pulmonary embolus, three wound problems and one sural nerve injury. Possibly this result represents a rather extreme version of incision of the tendon to encourage regneration. However, it is interesting that Mahieu (2007) found that eccentric exercise also resulted in increased dorsiflexion - it might be that this changes the biomechanics of Achilles function in a beneficial way which is yet to be understood.