The Relationship Between Tibial Tubercle-Trochlear Groove Distance and Noncontact Anterior Cruciate Ligament Injuries in Adolescents and Young Adults.
OBJECTIVE
To determine differences in tibial tubercle-trochlear groove (TT-TG) distance between patients with a history of noncontact anterior cruciate ligament (ACL) injury and an uninjured control group.


METHODS
MRI studies of 60 patients (age range, 14 to 25 years) with ACL-deficient (ACLD) knees were compared with 60 intact-ACL controls. All patients underwent MRI after a noncontact sports injury. TT-TG distances were measured on proton density-weighted axial images. Independent t-tests were used to determine differences in TT-TG distance between the ACLD and control groups.


RESULTS
The mean TT-TG distance in the ACLD group was 12.07 mm (95% confidence interval [CI], 11.11 to 13.02), compared with 10.44 mm (95% CI, 9.64 to 11.24) in the control group. The mean TT-TG distance in the male ACLD group was 12.95 mm (95% CI, 11.39 to 14.51), compared with 10.87 mm (95% CI, 9.52 to 12.21) in the male control group. The mean TT-TG distance in the female ACLD group was 11.48 mm (95% CI, 10.24 to 12.71), compared with 10.04 mm (95% CI, 9.06 to 11.02) in the female control group. There were statistically significant differences in TT-TG distance between the ACLD and control groups (P = .011) and between the male ACLD and control groups (P = .041).


CONCLUSIONS
In adolescents and young adults, the TT-TG distance was statistically larger in knees with noncontact ACL tears than in intact-ACL control knees. When the groups were stratified on the basis of sex, only the male patients showed a statistical difference, with a 2.08 mm increase in TT-TG distance between the ACLD and intact-ACL patients. No difference in TT-TG distance was found between the ACLD and control groups for female patients. Despite the findings of this study, the clinical significance of an increased TT-TG distance as an isolated risk factor for noncontact ACL injury remains unanswered.


METHODS
Level III, case-control study.
Department of Osteopathic Surgical Specialties, Michigan State University, East Lansing, Michigan, U.S.A.; Department of Orthopaedic Surgery, McLaren Greater Lansing, Lansing, Michigan, U.S.A.. Electronic address: sig1375@gmail.com.
Michael G
MG
Saper
Department of Osteopathic Surgical Specialties, Michigan State University, East Lansing, Michigan, U.S.A.; Center for Orthopedic Research, Michigan State University, Lansing, Michigan, U.S.A.
John M
JM
Popovich
Department of Radiology, Michigan State University, East Lansing, Michigan, U.S.A.
Ryan
R
Fajardo
Department of Osteopathic Surgical Specialties, Michigan State University, East Lansing, Michigan, U.S.A.; Department of Orthopaedic Surgery, McLaren Greater Lansing, Lansing, Michigan, U.S.A.
Shane
S
Hess
Department of Osteopathic Surgical Specialties, Michigan State University, East Lansing, Michigan, U.S.A.; Department of Orthopaedic Surgery, McLaren Greater Lansing, Lansing, Michigan, U.S.A.
Jeremy L
JL
Pascotto
Department of Osteopathic Surgical Specialties, Michigan State University, East Lansing, Michigan, U.S.A.; Department of Orthopaedic Surgery, McLaren Greater Lansing, Lansing, Michigan, U.S.A.; Michigan State University Sports Medicine, East Lansing, Michigan, U.S.A.; Department of Radiology, Michigan State University, East Lansing, Michigan, U.S.A.
Michael
M
Shingles
D000293:Adolescent; D000328:Adult; D000070598:Anterior Cruciate Ligament Injuries; D001265:Athletic Injuries; D016022:Case-Control Studies; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D057071:Patellofemoral Joint / Q000033:anatomy & histology*; D012189:Retrospective Studies; D012737:Sex Factors; D013977:Tibia / Q000033:anatomy & histology*; D055815:Young Adult