ISAKOS: 2019 Congress in Cancun, Mexico
ISAKOS

2019 ISAKOS Biennial Congress ePoster #725

 

Factors Affecting the Achievement of Symmetrical Six-Month Isokinetic Muscle Strength and Single Leg Hop Test Performance: A Cohort Study of 4,093 Patients with Primary Anterior Cruciate Ligament Reconstruction

Riccardo Cristiani, MD, Stockholm SWEDEN
Christina Mikkelsen, PT, Stockholm SWEDEN
Magnus Forssblad, MD, PhD, Stockholm SWEDEN
Bjorn Engstrom, MD, PhD, Assoc. Prof., Spanga SWEDEN
Anders Stalman, MD, PhD, Saltsjöbaden SWEDEN

Capio Artro Clinic, Stockholm Sports Trauma Research Center, Karolinska Institute, FIFA Medical Centre of Excellence, Stockholm, SWEDEN

FDA Status Not Applicable

Summary

Demographic factors, graft choice, concomitant meniscal surgery and cartilage injury affect the achievement of symmetrical isokinetic muscle strength and single leg hop test performance 6 months after primary anterior cruciate ligament reconstruction (ACLR).

Abstract

Purpose

To identify factors affecting the achievement of symmetrical isokinetic muscle strength and single leg hop test performance 6 months after primary ACLR.

Methods

Data, from 2000 to 2015, were extracted from our database. Patients who underwent primary ACLR and were assessed with the isokinetic quadriceps and hamstring strength tests and single leg hop test 6 months after surgery were included. Demographic data, information regarding graft used, cartilage injuries, and concomitant meniscal surgery were reviewed. Patients with a limb symmetry index (LSI) => 90% were considered to have achieved symmetrical isokinetic strength or single leg hop test performance. A logistic regression analysis was used to determine whether patient age (=>30 years vs. <30 years), gender, time from injury to surgery (delayed >3 months vs. not delayed <=3 months), pre-injury Tegner activity level (high =>6 vs. low <6), graft type (HT vs. BPTB autograft), cartilage injury, and the presence of medial meniscus (MM) or lateral meniscus (LM) resection or repair were factors associated with the achievement of symmetrical isokinetic quadriceps or hamstring strength and single leg hop test performance.

Results

A total of 4,093 patients (54.3% males) with a mean age of 28.3 ± 10.7 years were included. The proportion of patients that achieved a LSI=> 90% was 35.7%, 47.3% and 67.9% for isokinetic quadriceps strength, hamstring strength and single leg hop test respectively. Age => 30 years (OR, 0.47; 95% CI, 0.47-0.55; P<0.001), female gender (OR, 0.80; 95% CI, 0.70–0.91; P=0.001) MM repair (OR, 0.60; 95% CI, 0.43–0.84; P=0.003) and LM repair (OR, 0.61; 95% CI, 0.42–0.89; P=0.01) decreased the odds whereas the use of HT autograft (OR, 3.41; 95% CI, 2.48–4.69; P<0.001) increased the odds of achieving symmetrical quadriceps strength. Age => 30 years (OR, 0.85; 95% CI, 0.74–0.97; P=0.02), delayed (>3 months) ACLR (OR, 0.81; 95% CI, 0.68–0.97; P=0.02), HT autograft (OR, 0.40; 95% CI, 0.31–0.51; P<0.001) and cartilage injury (OR, 0.82; 95% CI, 0.69–0.97; P=0.02) reduced the odds of achieving symmetrical hamstring strength. Age => 30 years (OR, 0.60; 95% CI, 0.51–0.70; P<0.001), female gender (OR, 0.64; 95% CI, 0.55–0.75; P<0.001), delayed (>3 months) ACLR (OR, 0.70; 95% CI, 0.57–0.87; P<0.001), MM resection (OR, 0.73; 95% CI, 0.60–0.90; P=0.003), MM repair (OR, 0.71; 95% CI, 0.51–0.99; P=0.04) and cartilage injury (OR, 0.78; 95% CI, 0.65–0.95; P=0.01) decreased the odds whereas high pre-injury Tegner activity level (=> 6) (OR, 1.59; 95% CI, 1.26–1.99; P<0.001) and HT autograft (OR 1.95; 95% CI, 1.48–2.56; P<0.001) increased the odds of achieving symmetrical single leg hop test performance.

Conclusion

Demographic factors, graft choice, concomitant meniscal surgery and cartilage injury affect the achievement of symmetrical isokinetic muscle strength and single leg hop test performance 6 months after primary ACLR. Knowledge of these factors provides clinicians and physiotherapists with valuable information to counsel patients about their expected functional recovery and should be used to optimize rehabilitation and maximize knee function after primary ACLR.