A player suffered an ACL tear and you decided to explore the use of the Internal Brace. Can you tell us a little bit about that technique and how it differs from a traditional graft?

A traditional ACL reconstruction involves either removing or bypassing residual ACL tissue, with no attempt to repair the ligament, despite the fact that in the majority of cases sufficient tissue remains to at least consider a repair [1].

Historically, isolated ACL repairs have had high revision rates of up to 24%, so they are not normally considered for ACL tears [2]. However, traditional ACL reconstructions using autograft harvest (patella or hamstring) are commonly associated with anterior knee pain [3] and hamstring weakness, respectively [4].

The surgical technique used in this case was a bone-patellar tendon-bone autograft. This is a hybrid ACL reconstruction-repair using a small patellar tendon graft to reinforce the repaired ACL. In addition, an Internal Brace was used with suture FiberTape® to augment the reconstruction and provide extra protection during the healing and remodelling phases [5].

This type of procedure is biomechanically superior to the graft alone [6]. The Internal Brace allows for sufficient healing while protecting the ligament during the crucial period of remodeling. It thereby acts as a scaffold, where the ligament grows through the lattice structure of the Internal Brace supporting the regeneration of the injured ACL [1].

Because this procedure repairs the patient’s ACL, it retains its natural tissue, including nerves and blood cells, which maintains its proprioceptive properties.

Can you briefly describe the exit and entry criteria of the task-based rehab protocol that you used in this ACL rehab?

The task-based rehabilitation protocol is split into four distinct phases following surgery: post operative recovery, progressive limb loading, unilateral load acceptance, and sports specific task training [7]. The programme required the player to complete certain tasks that would enable progression to the next stage of rehabilitation.

For the player to progress from the post op recovery phase, he had to have full range of movement, be able to squat to parallel, have a normal gait pattern and have sufficient gluteal and hamstring capacity, measured by short and long lever double leg bridges (>10).

To progress from the progressive limb loading phase, the player should be able to single leg squat for 10 reps and perform a bilateral drop jump test with a Quantitative Analysis of Single Leg Loading (QASLS) score of 0-1. We assessed gluteal, hamstring and calf capacity via unilateral short and long lever bridge positions from a 30cm box and heel raises off a step, with the pass mark being >25 with less than a five rep difference between limbs.

Progressing into the sports specific task training required symmetrical reach distance during a Star Excursion Balance Test, a QASLS score of 0-1 during a tuck jump test and a single leg hop, a triple hop and a crossover hop test with the threshold being <5% deficit compared to the uninjured limb and his pre-season baseline testing.

Finally, before progressing to unrestricted training, the player would need to complete isokinetic testing, change of direction and agility test and T-test as well as performing sports specific tasks with alignment control under random practice and fatigue scenarios.

Given this new surgical technique, can you describe the difference in time frames between key rehab outcomes in this case versus more traditional surgical RTP cases?

A recent study found that the mean RTP time for elite UEFA soccer players after ACL reconstruction was 216 days (7.1 months) [8]. The player in this case study played his first match on day 171 (5.6 months). It is difficult to describe the difference in time frames around other key rehab outcomes, though, as current literature outside of this case study does not go into detail regarding the timing of key outcomes and exit criteria.

I believe that part of the reason the player returned significantly earlier than average is that the surgical technique used in this case gave him the best possible start to his rehabilitation programme. The player had minimal post-operative swelling, which meant he had a normal gait pattern after only nine days. Due to the ability to load his knee early, thanks in part to the Internal Brace, the player suffered minimal atrophy during the initial phase of rehab. That meant he was able to return to a traditional strength programme much sooner than expected.

There were other contributing factors that enabled this, too, including pain management, compression, cryotherapy, blood flow restriction training (BFR) and BFR combined with neuromuscular electrical stimulation.

Also remember that the player was 100% committed to this rehabilitation protocol. Prior to his injury, he was one of the quickest and strongest athletes. He was also a tee-totaller, had a good family support network and was extremely motivated to return to football as soon as possible due to being in the final year of his contract.

How did the return to training and return to competition go for this athlete following the ACLR?

Following the player’s surgery, we designed an RTP macrocycle with the end goal at the forefront of the process, then reverse engineered different elements of the rehabilitation process, mapping out rough timing estimates for each stage of rehab. That way, if the player progressed ahead of schedule, we could bring his RTP date forward. Conversely, if the player had not reached a stage in the expected timeframe, then we could shift the RTP date back.

The player began his RTP early but gradually. His first involvement in team training was on day 111, when he took part in controlled passing drills. He then progressed to SAQ drills and modified Rondo games with the team over the following 2-3 weeks, while continuing to work on single leg landing under fatigue, as well as progressing his reactive change of direction and cutting drills.

Then, upon completion of the majority of his RTP exit criteria, he took part in a non-contact training session on day 144. Shortly after this and upon completion of his final exit criteria, he took part in his first unrestricted session on day 149. He then completed three weeks of unrestricted training before taking part in a friendly match during the Scottish Premier Leagues winter break on day 171, where he was limited to 45 minutes.

He returned to competitive action for his new team on day 193 following a loan move at the end of the winter transfer window. This loan move would ultimately lead to the player signing for that club on a three year contract, securing his long term future.

What results have you seen in the period following the athlete’s return to competition in the medium / long term?

Thankfully, the player has not suffered a recurrence of his ACL in the 4.5 years since his return to play. Having spoken to him recently, he also reports that he has not missed a day’s training due to any other soft tissue injury. Although he has not been part of the match day squad for matches since his return from injury, this has been for tactical reasons only.

Since his return from his ACL injury, the player has played 132 professional matches and continues to play professionally at 36 years old.

Reflecting on the rehab process, could you have done anything to accelerate the RTP process even further?

I remember our department put every resource we had into the planning and the delivery of this rehabilitation. We met regularly as a department, but we also met regularly with the player to discuss his progress and how to continue to push towards the best possible outcome. This was based on a BJSM editorial by King et al, who suggested involving the athlete in the multi-disciplinary team and putting them at the centre of the decision making process would empower the athlete and subsequently improve rehabilitation outcomes [9].

With regards to accelerating the RTP process, at the time we did not have any Forcedecks equipment that is now commonplace in most professional training grounds.

Upon reflection and based on how I rehabilitate ACL now and the additional exit criteria I use, having access to this type of equipment may have helped us with our decision making processes along the way. However, given the athlete would still have been required to complete all the previously mentioned exit criteria, I am undecided whether this could have helped accelerate the player to return any sooner than he did.

Video link to entire rehab below: