Thermal modification of partial tears of the anterior cruciate ligament.
OBJECTIVE
Partial tears of the anterior cruciate ligament (ACL) are common, representing 10% to 28% of all ACL tears. Untreated partial tears of the ACL may go on to complete rupture in up to 42% of cases, and as few as 30% of patients return to their preinjury activity level. The purpose of this study was to evaluate the effectiveness of thermal modification for the treatment of partial tears of the ACL.


METHODS
A prospective, nonrandomized consecutive case series.


METHODS
Thirteen patients with a partial tear of a native ACL were treated with thermal modification of the ACL. All patients had a preoperative office examination significant for an end-point to Lachman examination and pivot-glide. All patients had bilateral preoperative KT-1000 measurements. All tears were confirmed by arthroscopy to constitute a 50% or less loss of structural integrity of the ligament. The ACL underwent thermal modification using the Oratec thermal probe (Oratec Interventions, Menlo Park, CA), and was examined by intraoperative KT-1000 testing. Patients were evaluated postoperatively at 6 weeks, and at 3, 6, 12, and 24 months by office examination and functional outcome scoring.


RESULTS
KT-1000 arthrometer testing revealed a mean side-to-side difference of 4.35 mm preoperatively (SD = 1.1 mm). At the most recent follow-up, averaging 23 months (range, 18 to 28 months), 10 patients had a negative Lachman examination and no pivot-shift. Two patients had persistent grade II Lachman and complaints of giving way 3 months postoperative. Both patients underwent ACL reconstruction. One patient was lost to follow-up. Of the remaining 10 patients, all patients achieved full extension, and the average flexion range of motion was 131 degrees (SD = 5.6). Compared with the preoperative KT-1000 arthrometer testing, the most recent evaluation revealed a decrease in mean side-to-side difference to 1.9 mm (SD = 1.5 mm). At most recent follow-up, the mean Lysholm score was 96.3 (SD = 4.4), the mean Tegner score was 6.1 (SD = 1.2), and the mean Cincinnati score was 94 (SD = 3.0).


CONCLUSIONS
With cautious application, thermal modification may be a viable treatment option for partial tears of the ACL in a select subset of patients. Further investigation is necessary to determine the long-term effectiveness of this procedure.


METHODS
Level IV, Therapeutic Case Series Study (no or historical control group).
Lamar
Daniel S
DS
Department of Orthopaedic Surgery, University of Pennsylvania, Pennsylvania, USA.
Bartolozzi
Arthur R
AR
Freedman
Kevin B
KB
Nagda
Sameer H
SH
Fawcett
Clifford
C
D000328:Adult; D016118:Anterior Cruciate Ligament / Q000601:surgery*; D000070598:Anterior Cruciate Ligament Injuries; D001182:Arthroscopy / Q000379:methods*; D003131:Combined Modality Therapy; D005500:Follow-Up Studies; D006801:Humans; D006979:Hyperthermia, Induced; D007718:Knee Injuries / Q000601:surgery* / Q000628:therapy; D008875:Middle Aged; D016119:Posterior Cruciate Ligament / Q000293:injuries* / Q000601:surgery*; D019651:Plastic Surgery Procedures / Q000379:methods*; D017211:Treatment Failure; D016896:Treatment Outcome