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Reliability of an In Vivo measure of Achilles Tendon strainR. Clark1*, K. Crossley1, L. Buckley, S. Bartold & A. Bryant1The Centre For Health, Exercise And Sports Medicine, School Of Physiotherapy, The University Of Melbourne

The aim of this experiment was to determine the repeatability of an in vivo measure of Achilles tendon strain. Ten athletic, female subjects performing >20kms per week of endurance running volunteered to participate in this study. Maximal isometric plantarflexion efforts were performed on a calf-raise apparatus whilst synchronous real-time ultrasonography of the triceps surae aponeurosis was recorded. Connective tissue length (L

o) of the triceps surae complex was measured and tendon strain was calculated

by dividing aponeurosis displacement (ΔL, mm) during plantarflexion by Lo. This test was performed three times for each subject, with a mean Achilles tendon strain value

taken from these recording. This test was then repeated after 14 days, with an absolute agreement ICC assessment of repeatability performed. The results showed a mean 5.1 + 1.9% and 5.5 + 2.4% Achilles tendon strain during the first and second tests respectively. This analysis revealed that the test was reliable, with an ICC value of R=0.891. Based on these findings, this method of assessing tendon strain was deemed acceptable for use in a test-retest situation.

Medial Patello-Femoral ligament reconstruction in the skeletally immature: a retrospective study of 15 knees in 13

children and adolescents.G. Cowen1*1Perth Orthopaedic And Sports Medicine Clinic

Treatment of patello-femoral instability is a source of much controversy, especially in the skeletally immature population where only soft tissue realignment procedures are indicated. We report the outcome of MPFL reconstructions using hamstring graft in such skeletally immature individuals operated on by the senior author (PA) between 2000 and 2006. The cohort was taken from both the private and public sector. The study group comprised of a total of 13 skeletally immature individuals, eight male and 5 female. 2 in the group had bilateral surgery. The age range of the group was 7 – 15 years. Follow up to date includes 7 knees operated on in 6 patients. Average age at time of procedure was 13.9y and at follow up 16.9y. Gracilis tendon was used in two procedures and semitendinosus tendon in the other 5 procedures. Mean stay in hospital was 2 nights. Mean return to school was 2.8 weeks and to competitive sport 8.8 months. Only 1 patient continued to complain of recurrent subluxations post-procedure and despite this reported a subjective feeling of 90% stability. There was no leg length discrepancy. All patients reported an improvement in Kujala Knee Scores and Tegner Activity Scores at final assessment. All patients had post operative MRIs at follow up to assess graft position and patency. The addition of MPFL reconstruction to lateral release demonstrates high rates of patient satisfaction and reported knee security and return to sporting activity. There has been no hamstring donor site morbidity to date.

Obturator nerve entrapment – diagnosis (including imageing) and surgical managementD. Kelly, J. Garvey, J. Reid & L. Henschke1*1Hunter New England Health (NSW)

Entrapment of the obturator nerve in the fascia deep to the Adductor longus insertion has been described as a cause of groin pain in Australian Rules Footballers (Bradshaw et al). We report here a case of an Obturator neuroma diagnosed pre-operatively by ultrasound after which surgical release resulted in an effective cure of symptoms.A forty-year-old cyclist having been hit from the side by a car 3 years previously sustaining severe blunt trauma. The cyclist complained of numbness down the inner aspect of his left thigh and a pulling sensation in the left testicle. In spite of cortisone injections into the back and anti-inflammatory medications, symptoms did not improve over a 2-3 year period. On examination, the insertion of the left Adductor longus tendon was painful and the squeeze test was positive in the 180 and 90 degree positions. There was bluntness to pin-prick sensation in the distribution of the left Obturator nerve. An Ultrasound diagnosis of left-sided Adductor tendinopathy and an entrapment neuroma of the left Obturator nerve was made. At operation a tight gritty left Adductor longus tendon was encountered which was released and the fascia overlying the Obturator nerve on Adductor brevis was incised by dissection and the nerve was released from its entrapped state. Subsequent follow up showed complete resolution of symptoms and the cyclist was able to resume his pre-injury level of activity. This case illustrates that the Obturator nerve may be entrapped by post-traumatic processes that result in ‘neuroma’ formation, and that imageing can occasionally demonstrate these changes.

The Anatomic Double Bundle ACL Reconstruction: Are two bundles better than one?J. Herald1*1Sports Doctors Australia

Introduction: There have been significant advances in ACL reconstruction over the past 30 years, however outcomes are not perfect. A critical review of the literature from the last 10 years demonstrates between 10-30% of patients complain of persistant instability following single bundle reconstruction. Double bundle reconstruction has been developed following further understanding of the functional anatomy of the ACL. Method: Eleven studies in the published literature on double bundle ACL reconstruction compared with single bundle reconstruction were reviewed and their results compiled. The level of evidence of evidence of each paper was considered when trying to draw conclusions from the paper. Results: No Long term data is available but short term data over a 2 year period suggests better restoration of kinematics and clinically better rotational stability with a trend towards a better pivot shift. A persistent pivot shift has been linked with a risk of osteoarthritis. Thus a double bundle reconstruction may result in less osteoarthritis in time, however long term data is needed to confirm this. There was no difference in the KOOS and IKDC subjective scores or AP laxity with the KT-1000 arthrometer in the short term. Conclusion: The double bundle reconstruction has better dynamic rotational stability on pivot shift and better knee kinematics than a single bundle reconstruction but does not have proven clinical superiority to date.

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