Unfortunately, too many athletes who recover from ACL tears go on to suffer another injury within a short period of time. Click here to read a prior post on secondary injuries. There are differing opinions on when or if there is an exactly “right time” to clear an athlete for return to play.

We already know that athletes have persistent weakness and asymmetry at 1 year post-op and even beyond. I recently had one of my collegiate soccer players re-tear while helping out with a youth soccer camp. She had not yet done hop testing with me or been cleared for full soccer, but as she was 1 year out she did not think it would be an issue playing with 12 year-old girls. It only took 20 minutes before she suffered a non-contact re-injury and lateral meniscus tear.

Consider the following paper that reveals low rates of patients meeting return to sport (RTS) criteria at 9 months post-op:


Another paper recent published in the Journal of Sports Rehabilitation revealed marked deficits in balance and hop testing at 6 and 9 months post-op:


A recent paper in the American Journal of Sports Medicine (https://www.ncbi.nlm.nih.gov/pubmed/29659299) lists positive predictors of a return to knee-strenuous sport 1 year after ACL reconstruction were male sex, younger age, a high preinjury level of physical activity, and the absence of concomitant injuries to the medial collateral ligament and meniscus.

In 2016, research in the American Journal of Sports Medicine revealed delaying return to sport at least 9 months markedly reduced re-injury risk in those who passed RTS testing. Click below for more on that study:


So, where are we now? I employ multiple functional tests including the Y-Balance Test, FMS, single leg squatting, hand held dynamometry, hop testing, qualitative movement assessment and jump landing assessments. But, is that enough?

According to a recent paper published in The International Journal of Sports Physical Therapy, the standard hop testing and isokinetic testing may not give us the whole picture in terms of readiness for RTS. Ebert et al. compared the ‘Back In Action’ test to the the more standard measures described in the past for return to play testing. They evaluated 40 subjects (25 men, 15 women) at a mean of 11.3 months after ACLR utilizing a hamstring autograft. The man age of participants was 23.8 years old. Patients had undertaken rehabilitation at different clinics from various therapists so that should be noted.

The participants all performed the 4 hop tests (single, triple, triple cross-over and 6 meter timed) Isok strength testing was done at 90 degrees/second. Then, they did the BIA battery. The BIA test package comes with a laptop, accelerometer and waistband, MFT Challenge Disc, and the Speedy Basic Jump Set.

The ‘Back In Action’ battery consists of:

  • Double leg stability test
  • Single leg stability test
  • Double eleg counter-movement jump (CMJ)
  • Single leg CMJ
  • Plyometric jump test (4 consecutive plyometric jumps)
  • Speedy jump test
  • Quick feet test


While using a 90% or greater cut-off for passing the hop testing, only 67.5% passed. While combining this along with the same criteria of the isokinetic testing, only 42.5% passed both. When employing the BIA battery, only one participant (2.5%) passed all criteria to return to sport. Collectively, the participants’ limb symmetry indices for the 4 hop tests were significantly higher than for the two BIA functional single limb test (single leg CMJ and speedy jump test).

When considering the single limb CMJ in the BIA, 29 participants were below average in the operated limb, while 15 participants were still below average on the non-operated limb. This was also the case for the Speedy test as 28 (70%) and 24 (60%) were below average on the operated and non-operate limbs. Event he four-jump plyometric test revealed that 63% of participants were below average.


  1. This paper only looked at HS autografts in patients who did not have uniform rehab across multiple providers, so these results cannot be generalized beyond the group in the study.
  2. Standard isokinetic and traditional hop testing may not be enough to evaluate readiness for level 1 jumping/cutting sports (e.g. volleyball, basketball, soccer). We must continue to refine our functional testing parameters. There are several assessments available indulging the LESS, tuck jump assessment and others. Work to find a system that works for you and your clients.
  3. We should not be in a hurry to send athletes back onto the field if we measure or see asymmetry as it only increases their risk for a secondary injury.
  4. We must consider many factors including psychological readiness, male versus female, overlying quad strength, concomitant injuries and graft choice as we make RTS decisions.
  5. Work with the MD, ATC, and patient/family to communicate collectively as a team to ensure the safest, most effective return to play transition possible, while setting realistic expectations from the beginning. This should be an individual process as no two rehabs are exactly alike.