Arthroscopic Surgery for Patellar Tendonitis: A One to Four Year Follow Up Study

D P Johnson

The histological appearances of patellar tendonitis were reported by Martens in 1982, and assumed to represent a micro fracture or a partial rupture of the tendon. Surgical techniques are sometimes required in the management and include detachment of the patella tendon from the inferior pole, excision of the degenerative nodule, drilling, or excision of the inferior pole, which are all reported to be successful in 60 - 90% of cases. In a previous study of the radiological and MRI appearances in this condition, a normal morphology of the patella, and an increased high signal intensity in the superior, central and posterior aspect of the tendon was noted. It was, proposed that a possible pathogenesis for this condition may in fact be an impingement or compression of the inferior pole of the patella onto the posterior aspect of the tendon in flexion. If correct, the surgical rational should be to release the deeper fibres of the tendon from the inferior pole and to surgically excise the tip. An inital study of 20 patients treated by arthroscopic decompression and marginal excision of the inferior pole was first presented 2 years ago. This study analysed the 1-4 year results in a larger population.

We analysed a population of 35 patients with patella tendonitis resistant to conservative treatment undergoing release of the deep central aspect of the tendon and excision of the inferior pole undertaken as a wholy arthroscopic procedure with a 1-4 year follow up. The patients had significant grade III patella tendonitis. The technique included elevation and partial excision of the superior central part of the fat pad to reveal the bare area of the patella. Elevation of the patella tendon fibres from the anterior 5 millimetre surface of the inferior pole of the patella, and excision of the exposed inferior pole. Patients were mobilised and discharged as a day case in over 50 per cent of cases. The average operating time was 45 minutes. There was no instance of instrument breakage. No conversion to an open procedure or operative complications. There were no re-admissions for haemarthrosis. Final review revealed that 90% of patients had good or excellent results. One patient had a fair result, one had a poor result. Patients returned to work on average in 2 weeks, sport on average in 9 weeks, became symptom free in 10 weeks, and returned to competition on average in 13 weeks following surgery.

We, therefore, concluded that decompression of the inferior pole of the patella by elevation of the central portion of the tendon from the inferior pole and excision of the inferior pole without specific excision of the degenerative lesion was successful in 90% of cases. It was technically feasible to undertake this as a day surgery arthroscopic procedure with rapid rehabilitation. We are currently analysing histological specimens from 8 cases of patellar tendonitis, but the previously reported appearances are compatable with a chronic repetative posterior impingement on the tendon. We have previously suggested a new patho-aetiology of patellar tendonitis; of a posterior impingement to the tendon and subsequent degeneration. The results of this study certainly support this aetiology of the condition. The condition is best investigated by MRI, surgical treament should be aimed at release of the deep fibres of the tendon from the patella and excision of the tip of the inferior pole. This can reliably, safely and successfully be undertaken as an arthroscopic day surgery procedure.

<<back to research index

+ top

© The Bristol Orthopaedics and Sports Injuries Clinic 2003. The Bristol Knee Clinic is a trading name of the Bristol Orthopaedic Clinic Ltd. privacy / copyright | contact | Powered By Create Medical