Determination of patellar tendon length for anterior cruciate ligament reconstruction using an anteroposterior knee radiograph

Background/Objective: Graft-tunnel length mismatch is a common intraoperative technical problem for anterior cruciate ligament reconstruction (ACLR) using a bone-patellar tendon-bone graft (BPTB). The patella-to-condyle and the patella-to-notch distances are two measurements in an anteroposterior knee radiograph. The objective of this study was to evaluate the sensitivities, specificities and reliabilities of those 2 measurements for detecting patients who had a patellar tendon length exceeding 45 mm. Methods: Preoperative plain radiographs of patients who underwent ACLR with a BPTB graft were evaluated independently by two orthopaedic surgeons 3 times each at 2-weekly intervals. The sensitivities and specificities of the two measurements for detecting patients who have a patellar tendon length exceeding 45 mm were calculated. The optimal cutoff point was estimated using Youden index, and the receiver operating characteristic (ROC) curve and area under the curve (AUC) were evaluated with a 95% CI. As for the inter- and intra-rater reliabilities, intraclass correlation coefficients (ICC) were determined. Results: One hundred and twenty-seven patients with an average age of 29.5 years old were evaluated. The mean patellar tendon length was 41.3 ± 5.0 mm. Patients with a length more than 45 mm (20 patients, 16%) had significantly higher patella-to-condyle and patella-to-notch distances, and more frequent use of bone staples for distal graft fixation than patients with a length ≤ 45 mm. To detect patients with a patellar tendon length over 45 mm, the optimal cutoff point for the patella-to-condyle distance was set at 14.5 mm, which had a sensitivity of 80%, specificity of 71%, and AUC of 0.76. In the case of the patella-to-notch distance, the cutoff point of 5.5 mm had a sensitivity of 80%, specificity of 66%, and AUC of 0.73. The intra- and inter-rater reliabilities of the two measurements were excellent, with ICCs of over 0.90. Conclusions: Preoperative measurements of the patella-to-condyle and the patella-to-notch distances in AP knee radiographs can be valuable tools, with good sensitivities and specificities, for the determination of the patellar tendon length when using a BPTB graft for an ACLR. They had an acceptable level of discrimination capability and excellent reliability. Keywords: Patellar tendon length, Anterior cruciate ligament reconstruction, Bone-patellar tendon-bone graft, Graft-tunnel length mismatch, Radiographic measurement, Anteroposterior knee radiograp

Quantifying anterior knee pain during specific activities after using the bone-patellar tendon-bone graft for arthroscopic anterior cruciate ligament reconstruction

Background/objective: There has been much debate about the optimal graft choice for an anterior cruciate ligament (ACL) reconstruction. Anterior knee pain is a common donor site problem when using a bone-patellar tendon-bone (BPTB) graft. However, knowledge of the characteristics of anterior knee pain during different daily activities is still limited. This study aimed to determine the incidence of anterior knee pain and to quantify the degree of pain during a range of daily living activities. Methods: Thirty-five patients who were scheduled to undergo an ACL reconstruction with an autologous BPTB graft between February 2015 and December 2016 were enrolled. A visual analogue scale (VAS) for pain was recorded during each of the following activities: ascending at 30-degree slope, ascending and descending stairs, running, jumping, squatting, kneeling, sitting cross-legged, and sitting one-legged. Demographic data, the range of motion, the area of decreased sensation, and the IKDC score were collected and compared 3 and 6 months postoperatively. Results: The 35 male patients had a mean age of 29.7 years. Postoperatively, the mean IKDC scores were 58.1 ± 9.8 at 3 months and 72.7 ± 10.5 at 6 months. The incidences of overall anterior knee pain were 62.9% and 34.3% at the 3- and 6-month time points. Kneeling was the only activity that produced severe pain. At 3 months postoperatively, kneeling's mean VAS pain score was 3.9 ± 2.9 (2.9, 4.9; 95% CI for mean for 17 patients [48.5%] with considerable pain), whereas at 6 months postoperatively, it was 2 ± 2.5 (1.2–2.9; 95% CI for mean for 9 patients [25.7%] with considerable pain). The area of numbness of the proximal leg decreased from 12.8 ± 18.3 cm2 (6.4, 19.2; 95% CI for mean) to 3.2 ± 9.1 cm2 (0.1, 6.5; 95% CI for mean) at 3 and 6 months postoperatively. Conclusions: Kneeling was the most challenging activity in terms of creating considerable levels of anterior knee pain in patients who had undergone an ACL reconstruction using a BPTB graft. Other knee activities, however, did not create moderate or severe degrees of anterior knee pain. Both anterior knee pain and numbness at the proximal leg improved over time.Trial registration number: TCTR2018–0630002. Keywords: Anterior cruciate ligament reconstruction, Anterior knee pain, Bone-patellar tendon-bone graft, Incidence and kneelin

Anterolateral ligament anatomy: a comparative anatomical study

Some anatomical studies have indicated that the anterolateral ligament (ALL) of the knee is distinct ligamentous structure in humans. The purpose of this study is to compare the lateral anatomy of the knee among human and various animal specimens. Fifty-eight fresh-frozen knee specimens, from 24 different animal species, were used for this anatomical study. The same researchers dissected all the specimens in this study, and dissections were performed in a careful and standardized manner. An ALL was not found in any of the 58 knees dissected. Another interesting finding in this study is that some primate species (the prosimians: the red and black and white lemurs) have two LCLs. The clinical relevance of this study is the lack of isolation of the ALL as a unique structure in animal species. Therefore, precaution is recommended before assessing the need for surgery to reconstruct the ALL as a singular ligament.Heinz EndowmentsUniv Pittsburgh, Dept Orthopaed Surg, Sch Med, 3471 Fifth Ave,Suite 1011, Pittsburgh, PA 15213 USAUniv Fed Sao Paulo, Dept Orthopaed Surg, Sao Paulo, SP, BrazilMahidol Univ, Dept Orthopaed Surg, Fac Med, Siriraj Hosp, Bangkok, ThailandUniv Pittsburgh, Dept Mech Engn & Mat Sci, Pittsburgh, PA 15260 USAKent State Univ, Dept Anthropol, Sch Biomed Sci, Kent, OH 44242 USAUniv Fed Sao Paulo, Dept Orthopaed Surg, Sao Paulo, SP, BrazilWeb of Scienc