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Evaluation of Stem Cell Therapies in a Bilateral Patellar Tendon Injury Model in Rats
Published on: March 30, 2018
[The semitendinosus tenodesis for recurrent dislocation of the patella in adolescents]
M Letts1, D Davidson, P Beaule2
1Department of Surgery, Children's Hospital of Eastern Ontario, 401 Smyth Road, K1H 8L1, Ottawa, Ontario, Kanada.
Objectives:
Correction of recurrent dislocation of the patella in children using a semitendinosus tenodesis and a double breasting of the medial retinaculum.
Indications:
Recurrent lateral patellar sub- or dislocation in skeletally immature patient. Patella alta with recurrent subluxation of the patella. Patella dislocation in the presence of generalized ligmentous laxity.
Contraindications:
Degenerative changes of the patellofemoral joint. Congenital dislocation of the patella.
Surgical Technique:
First incision at the posterior aspect of the thigh: division of the semitendinosus at its musculotendinous junction. Its muscle belly is sutured to the semimembranosus. Second incision over the pes anserinus: the tendon is delivered through this wound. Third incision over the inferior pole of the patella: division of the lateral patellar retinaculum. Passing of the semitendinosus tendon through a drill hole in the patella from mediodistal to proximolateral and fixation at the proximal pole of the patella. Double breasting of the medial patellar retinaculum.
Results:
Between 1990 and 1997, 29 children (5 boys, 24 girls) were operated for a recurrent patellar dislocation. Average age at surgery: 14 years and 3 months (7 years and 8 months to 17 years and 10 months). Preoperatively, pain was present in 19 out of 34 knees, ligamentous laxity in 13, a positive apprehension sign in 12, and a patellar hypermobility in 11. Average length of follow-up: 3 years and 2 months (1 year to 7 years and 2 months). Twenty-seven out of 34 knees were asymptomatic and the children returned to normal activities. Patellofemoral pain persisted in 7 children. A medial patellar subluxation occurred in 1 child. A medial release led to a good result.

