6 Month Outcome Comparison of a Potential Coper and Non-coper

Abstract

PURPOSE: To determine the effects of perturbation training on a non-coper and potential coper. METHODS: Quadriceps strength was tested using burst superimpositioning. Subjects were screened (single hop and timed hop, self-report questionnaires (KOS-ADL and global rating (GR) of perceived function), and number of knee give ways). One subject (PC) passed the screen (>80% on timed hop compared to uninvolved leg, >80% KOS, >60% GR, less than 1 episode of giving way) and the other (NC) failed due to 3 episodes of give-way. Both underwent 10 perturbation training sessions and a followup functional test, including tests in the screen plus triple and cross-over hops. Subjects could return to sport if they presented with >90% quadriceps index (QI) and each hop test (involved/uninvolved), and >90% KOS-ADL and GR. Subjects returned at 6 months for a repeat functional test. RESULTS: Post-training functional test: PC passed RTS criteria. NC passed criteria for the single and timed hop, and increased his QI, KOS-ADL and GR. 6-month follow-up: Both subjects passed all RTS criteria. Symmetry values improved for each (PC 98% - 112% in hops; NC 96% - 102% in hops). NC had a greater improvement from screen to follow-up in involved MVIC (NC +20%, PC +6%), single hop (NC +11%, PC +5%), KOS-ADL (NC +9%, PC +6%) and GR (NC +35%, PC +6%). Sport participation: Subjects were issued a de-rotational brace for use during sport. PC returned to skiing and recreational basketball, however he did not feel stable playing soccer and opted for surgery. Without first passing RTS, NC returned to basketball involving cutting, jumping, acceleration and deceleration, with only one episode of giving-way (not braced). CONCLUSIONS: The greater improvement in KOS-ADL and GR of NC may be due to a ceiling effect for PC on these measures. The greater increases in the functional scores on the single hop and MVIC are most likely due to the low level of the patient at the time of screening. The values of the timed hop are similar in both subjects (PC 1.8s, NC 1.84s) NC achieved symmetry between legs, though it took longer than PC. The instability experienced by non-copers may be controlled with a de-rotational brace and symmetrical performance on hop testing, with return to high level sports. These patients may need a longer period of training to achieve this functional status.