My evolution in the use of UTC

Ultrasound Tissue Characterisation (UTC) is an ultrasound that provides a 2D image in all 3 planes (transverse, sagittal & coronal), helping to try and provide a 3D image of the tendon. Based on the signals that it receives back, it helps to provide insight on how well the collagen fibres are aligned. Green represents straight, well aligned fibres, blue represents less continuous fibres, red represents a mainly fibrillar matrix, and black represents complete disorganisation with tendon being replaced by amorphous matrix and fluid (Rosengarten 2013). It was a tool that was originally utilised in the horse racing community to objectively monitor the integrity of tendon collagen (Docking 2012)

Sam Rosengarten alongside Jill Cook around 10 years ago brought over the UTC to Carlton FC in Australia and performed a longitudinal study in AFL. What it showed was that when high volumes of load (an AFL game) were performed there was evidence of a transient change in tendon integrity (Rosengarten 2013). This returned back to baseline within 72 hours. This is no different to the work from Magnusson (2010) that showed the turnover of tendon following a long distance run returning back to baseline in 72 hours. I remember Sam telling me that he performed 300 hops in a single night to see if there were any changes. He saw that it wasn’t enough to elicit acute tendon changes that appeared on the UTC. Whether the resolution wasn’t high enough back then or there is a certain threshold that needs to be reached in order for observable changes to be seen is yet to be completely known. However, I think it’s the latter as tendon mechanical adaptations require a certain threshold to be achieved in order for material properties to change (Arampatzis 2007). 

My journey and philosophy over the use of UTC has certainly evolved throughout the years. I started getting involved with it in late 2014 when Sam asked me to help out with analysing and scanning individuals and athletes that would come into the clinic. I’d also use it with my own patients. For me it was a great learning curve as you’d hear why clinicians had referred in and get to hear some of the patient’s stories. We also had a lot of tendon rupture repairs come through and you’d see the longitudinal changes. It was interesting to see how much disorganisation there was even in those returning to high level function. In those days I really thought it was a great tool for the use of assessing progression in tendon healing following rupture, identifying intra-substance tears, and assessing if there was plantaris tendon involvement. One interesting case was a person who had an Achilles tendon rupture 18 months ago but was still extremely fearful of activity. The scan was able to show how well organised their tendon was and gave confidence to the individual to progress. In athletes it was often used as an exclusion tool. For some of the athletes it showed there was no disorganisation or reactivity that may have lead them down a more aggressive route or different interventional pathway. 

Although currently my feelings from previous have stayed the same, but I definitely see its use in the mitigation and prevention of tendinopathy or ruptures. Being now involved with serially scanning NBA players throughout the season you definitely see longitudinal changes. We know from previous work that although you don’t have to have pathology to have pain (tendinopathy & ruptures), those that do have pathology are at a higher risk of having symptoms (Malliaris 2006. Our role in the NBA now is to advise teams on at risk players and provide a monitoring system for them. An example was a time where we advocated for a player to either change his load or include tendon-loading interventions as we saw disorganisation in a high-risk area. Unfortunately due to the schedule and injuries to other players they weren’t able to intervene the athlete ruptured their Achilles tendon. Now I’m not saying we can predict with certainty as there have been other players with a similar UTC presentation that don’t rupture, but it is about identifying risk and looking to mitigate this. 

Arampatzis A, Karamanidis K, Albracht K. Adaptational responses of the human Achilles tendon by modulation of the applied cyclic strain magnitude. J Exp Biol. 2007;210(Pt 15):2743‐2753. doi:10.1242/jeb.003814

Docking SI, Daffy J, van Schie HT, Cook JL. Tendon structure changes after maximal exercise in the Thoroughbred horse: use of ultrasound tissue characterisation to detect in vivo tendon response. Vet J. 2012;194(3):338‐342. doi:10.1016/j.tvjl.2012.04.024 

Magnusson SP, Langberg H, Kjaer M. The pathogenesis of tendinopathy: balancing the response to loading. Nat Rev Rheumatol. 2010;6(5):262‐268. doi:10.1038/nrrheum.2010.43

Malliaras P, Cook J, Ptasznik R, Thomas S. Prospective study of change in patellar tendon abnormality on imaging and pain over a volleyball season. Br J Sports Med. 2006;40(3):272‐274. doi:10.1136/bjsm.2005.023846

Rosengarten SD, Cook JL, Bryant AL, Cordy JT, Daffy J, Docking SI. Australian football players' Achilles tendons respond to game loads within 2 days: an ultrasound tissue characterisation (UTC) study. Br J Sports Med. 2015;49(3):183‐187. doi:10.1136/bjsports-2013-092713