Search the Community

View this email in your browser Peak Performance Physical Therapy & Sports Training EVIDENCE-BASED PRACTICE UPDATE September 2018 Return-to-play hop testing: Are we being fooled? CURRENT EVIDENCE Wren TA, Mueske NM, et al. Hop Distance Symmetry Does NOT indicate normal landing biomechanics in adolescent athletes with recent ACL reconstruction. JOSPT. 2018; 48(8): 622-629. by Karen Napierala, PT, AT, MS, CAFS Background: The purpose of this study is to compare single-leg hop biomechanics following ACLR to both the contralateral non-operative limbs and a normal knee control group. They wanted to determine whether the gold standard of 90% hop distance symmetry should be used for return to sport readiness following ACLR surgeries in adolescents, and if it is associated with normalized biomechanics. Method: Forty-six 12-to-18-year-old patients along with 38 age-matched contralateral controls. ACLR at mean average following surgery of 7.2 months. Single Anterior Hop test (best of three) along with 3-D motion-analysis data were recorded in all three planes at initial contact and between initial foot contact and maximum knee flexion of the weight-bearing limb on landing. All subjects were tested before being cleared for full return to play. Thirty-eight controls of the same age, who participated in 3/week sporting activities, with no injury history, were tested to provide normative data. Patients were grouped for data analysis based on limb symmetry index (LSI) as symmetric (> 90%) or asymmetric (< 90%). Results: Thirty-eight percent of all patients tested were asymmetric hoppers, having similar contralateral non-operative hop distances to controls but significantly reduced hop on the reconstructed limb. The average LSI for asymmetric patients was 77%. The symmetric hop group, despite an LSI > 90%, only hopped an intermediate distance on both the operative and non-operative limbs. Asymmetric patients had lower operative side knee flexion moments and knee energy absorption compared with their contralateral side and with uninjured limbs. They also had lower peak hip and knee flexion angles on the operative side compared with their contralateral side and both sides of symmetric patients, greater plantar flexion at initial contact compared with contralateral side and controls. Peak dorsiflexion was less than both limbs of the symmetric hop group of patients. Symmetric patients had lower knee flexion moments (vs contralateral and controls) and lower knee energy absorption (vs contralateral). Symmetric patients had greater hip flexion angles and moments bilaterally (vs controls) and hip energy absorption. Both symmetric group limbs and operative limb of asymmetric patients showed lower average knee adduction moments (vs controls). The conclusion was that they used more ankle, and less knee on landing post operatively, and thus landed more stiffly after their surgeries. Take-off mechanics showed lower peak knee and hip flexion ROM on the operative side compared with the contralateral side. THE PEAK PERFORMANCE PERSPECTIVE ACLR is not uncommon in sports these days. At our clinic alone we have seen more than 200 such cases in the past 13 years. According to research, 7.7% of ACLR patients have revisions in the first 6 years, and 6% have contralateral ACL injuries (Hetrich et al AJSM 2013). The return to play (RTP) decision making factors following ACLR can include strength, endurance, proprioception/balance, dynamic stability, power. Objectively measuring these variables is crucial. A common example is hop testing. Wren et al chose the single Anterior Hop Test. We prefer the three-hop or three-hop crossover tests to better assess multiple acceleration/deceleration episodes for both distance and quality. However, Wren et al found that 8 of 11 patients who went on to second ACL injuries had passed 90% LSI criteria for Anterior Hop Test with the comparison only to contralateral limb post operatively. Is the contralateral leg that has been only semi-active for six months a valid comparison? Is the athlete’s ability to safely control landing mechanics of greater or lesser importance than pure distance values (i.e. LSI)? Wren et al addressed both the numeric distance comparisons along with a number of objective “quality” measures. In this study, the landing on a force plate allowed for calculating the quality measures above (kinetics/kinematics). Some key weaknesses remain that potentially cloud this data. Without proper verbal cuing, we see athletes, and the risk remains in studies like Wren's, which don’t specify that they used specific verbal cuing. The athlete may use opposite leg swing, or the bilateral arm swing can easily be used to gain distance. If not controlled for this, it could easily affect the LSI. Wren et al’s study did NOT indicate that these were controlled for. At Peak, hop tests are performed with the patient's hands on their hips to limit arm swing and verbal cuing to limit trunk and opposite leg swing. Wren et al’s study clearly shows that all ACLR patients (whether symmetric or asymmetric) hoppers compensate. We expect that limiting some of these compensations may provide more accurate distance data and we the PTs can focus on the quality of the landing. This study showed that the non-operative limb failed to return to normal hop function performance based on control group comparisons. Without pre-injury reference data, this study confirms that there is a risk of a skewed comparison that leads to prematurely defining the operative limb as successful. That begs the question as to reliance on LSI for RTP decision making risks sending athletes back prematurely. Surgeons are dependent on PT testing data to contribute to RTP data. We need to be discerning. Clinically, without this force plate video, and EMG data, we have to rely on visual assessment to determine some of the quality measures that Wren et al described, as best as possible. Distance alone is inadequate. Even symmetric hoppers were not symmetric at their knee. That emphasizes the need to control for compensations during testing, and provide observational assessments. Other studies have shown dynamic valgus landing mechanics to be a risk factor. We commonly see this as over pronation, or increased femoral IR/ADDuction when we see athletes showing excellent hop distances, but abnormal mechanics. That must be understood as a risk factor for RTP and pointed out to the surgeons. (Wren et al pointed out that LSI has limited value.) Suggestions: All athletes should undergo pre-season hop testing that would provide excellent comparison for a true normal and comparisons down the road for a potential injury. We need to have an increasing awareness of the quality of the tests without such extreme reliance only on the numeric distance. While “hanging our hat” only on numbers, Wren et al show in their study that “symmetric” distances still don't equal normal performances at that limb. Even the control groups in this study had 38% or more than 1/3 showing greater than 10% asymmetry. While the single anterior hop test is an option, more demanding tests of three rep anterior hop, or the three rep anterior crossover version are better indicators of function. Because of the well-understood side-to-side twisting mechanisms reported for ACL injuries, we use side to side (frontal) and rotational (*transverse) hop testing to more specifically mimic the athletic demands needed on the field. These tests allow us to qualitatively, qualitatively assess the readiness for dealing with those forces. We find these key, and these are not reported in literature. This allows us to directly analyze the ability to decelerate or control landing mechanics involving at-risk positions that will be necessary when they return to the field or court. Rehab and testing in this specific manner increases the athlete's confidence when returning because they have been properly prepared for the forces and tasks necessary to play. THE PEAK PERFORMANCE EXPERIENCE Katie stated: “I was disappointed at first in not returning quicker, but now I know that I really needed the extra time to get my ACL leg able to control running, cutting and stopping. I feel so much more confident now, and sometimes i even forget that my leg was injured!” History: Katie underwent bone-patellar tendon-bone ACLR. She progressed steadily but slowly, with her quad function lagging behind slightly. As the 6-month mark rolled around, she assumed that she was ready. She knew it didn't feel right, but all her friends had returned at six months. But she was not ready. We tested her at seven months and then four weeks later: Before 4 weeks later 90 degree rotational hop for 15 seconds: L22 R 29 L 26 Step down 6” 20# weights L 16 R 30 L 25 Calf raise 15# L 25 R 31 L 29 Anterior hop and stick L 22 in. R 34 in. L 29 Triple hop and land L 42 in. R 67 in. L 57 Hop landings showed asymmetric over pronation and related dynamic valgus upon impact. Katie subjectively reported feeling the asymmetries in testing, which explained the difficulty she was having with cutting to the right while on the left leg and left leg deceleration. We set her goals and gave her four more weeks to get closer. After continuing intense physical therapy focused on quad strength, power, frontal and transverse stability, she was able to demonstrate the substantial differences in testing shown above. The quality and quantity of her testing improved enough that she was ready to progress to soccer practice. She felt more confident and and looked much more competent when in the clinic, and on the field. I saw her play the next year and she was quick and confident on the soccer field. This year, two years after her surgery, I watched her triple jump and high jump, and she is still pain free. You can trust the Physical Therapists at PEAK PERFORMANCE to do a thorough evaluation, to search for related but underlying contributing factors to kinetic chain dysfunction, and to design exercise progressions that both respect tissue healing and creatively use biomechanics principles to prevent symptoms and optimize carryover to your patients' functional goals. Call us at 218-0240 to discuss your patient's specific needs. Karen Napierala, PT, AT, MS, CAFS Peak Performance is just minutes away from your patients in Penfield, Fairport, Pittsford, Brighton, Rochester and, of course, East Rochester. We promise Individualized, hands-on and biomechanically appropriate Physical Therapy for your patients. No "one-size-fits-all" approaches. We WILL go the extra mile and "dig deeper" to discover underlying causes for injury risk and delayed recovery using the most advanced Evidence Based methods available and, we’re able to make unique adjustments to exercise prescriptions to speed the return to function and to minimize or prevent symptoms from interfering. No surprises. No hassles. Confident your patient is in the right place.  COME VISIT US AT 161 E Commercial St Just 1 mile off 490 exit (585) 218-0240 www.PeakPTRochester.com This email was sent to << Test Email Address >> why did I get this? unsubscribe from this list update subscription preferences Peak Performance Physical Therapy · 161 East Commercial Street · East Rochester, NY 14445 · USA