Transphyseal Anterior Cruciate Ligament Reconstruction Research Articles

Allograft or autograft in skeletally immature anterior cruciate ligament reconstruction: a prospective evaluation using both partial and complete transphyseal techniques

ObjectiveWe compared autografts and allograft using partial and complete transphyseal anterior cruciate ligament (ACL) reconstruction techniques among skeletally immature individuals.MethodsMale and females younger than 18 and 16 years old, respectively, diagnosed with ACL tear from April 2006 to March 2012 entered the study. One group had four-strand hamstring autograft, and the other had tibialis posterior allograft reconstruction. Those who had allografts either had hyper-laxity or recurvatum.ResultsAchieved mean (± SD) 2000 International Knee Documentation Committee subjective score was not statistically different (P = 0.385) between allograft (n = 13) (84.3 ± 3.2) and autograft groups (n = 18) (85.6 ± 4.4). Mean Knee injury and Osteoarthritis Outcome Score (KOOS) subscale Knee-Related Quality of Life at 2 years was 78.0 ± 7.2 and 75 ± 7.4 for allograft and autograft groups, respectively (p = 0.261). Mean 2-year KOOS subscale Sports and Recreation was 82.1 ± 5.8 and 84.8 ± 6.6 for allograft and autograft groups, respectively (p = 0.244).No patient reported instability, giving way, or locking of the knee. Pivot shift test was negative in all patients; however, a minor positive Lachman test was found in six cases (46%) within the allograft group and seven cases (39%) in the autograft group. One postoperative septic arthritis was documented in the autograft group.ConclusionConsidering existing concern that joint laxity and recurvatum are among the precursors of non-contact ACL injury in adolescents, bone-patellar-bone autografts are not applicable in this age group because of the open physis; furthermore, considering that hamstring autografts are insufficient (size thickness and stretchability), we recommend soft tissue allografts for ACL reconstruction in skeletally immature patients.

FEMORAL NERVE BLOCK VERSUS ADDUCTOR CANAL BLOCK FOR ANTERIOR CRUCIATE LIGAMENT RECONSTRUCTION IN PEDIATRIC AND ADOLESCENT PATIENTS

Background Adductor canal block (ACB) is an alternative method to femoral nerve block (FNB) for post-operative analgesia for anterior cruciate ligament reconstruction (ACLR) in pediatric and adolescent patients. Prior studies have suggested that FNB is associated with persistent strength deficits at 6 months after ACLR in this population. Proponents of the ACB consider that this method may result in a decreased incidence of quadriceps strength deficits during post-operative rehabilitation. The purpose of this study was to compare knee strength and function at 6 and 9 months after ACLR in pediatric and adolescent patients who received FNB versus ACB peri-operatively. Methods Patients 18 years or younger who underwent primary ACLR between 2002 and 2017 at a single institution were identified. ACLR was performed with either a patellar tendon autograft or hamstring autograft. A transphyseal ACLR was performed in patients with open physes. All patients participated in a comprehensive rehabilitation program which included isokinetic strength testing and functional testing at 6 and/or 9 months postoperatively. Patients were excluded if they underwent multiligamentous knee reconstruction, concomitant cartilage restoration procedures, did not receive perioperative FNB or ACB, or if they did not complete isokinetic strength and functional testing at 6 or 9 months. The included cohort was separated into FNB group and ACB group for comparison. Isokinetic extension and flexion strength deficits and functional deficits in vertical jump, single hop, and triple hop between the two groups were compared at both time points. A strength deficit of 15% or less and a functional deficit of 10% or less compared to the contralateral side were considered satisfactory. Univariate analysis was performed to assess for differences in patient demographics and surgical variables. A 1:1 matched subgroup analysis between the two groups was performed to account for possible differences in outcomes associated to graft types, concomitant meniscus repair, and BMI. Results Of the 240 patients identified, 85 patients (64 FNB, 21 ACB) with a mean age of 15.9 years (Range: 11-18) met inclusion criteria for comparison at 6 months and 76 patients (40 FNB, 36 ACB) with a mean age of 15.5 years (Range: 12-17) met inclusion criteria for comparison at 9 months. Univariate analysis showed significantly greater deficits at 6 months in the FNB with respect to fast isokinetic flexion strength (7.7% vs. -4.9%; p = .03). There were no differences in slow isokinetic flexion (10.5% vs. 6.8%; p = .79) and fast isokinetic extension (11.9% vs. 13.9%; p = .68) strength deficits between the groups. There were clinically relevant greater deficits in the FNB group with respect to slow isokinetic extension (19.3% vs. 12.0%; p = .24), but this did not reach statistical significance. This clinical difference in satisfactory scores between the groups with respect to slow isokinetic extension was accentuated with the 1:1 matched outcome trial (23.9% vs. 12.1%; p = .20). With respect to function, there were no differences in deficits for vertical jump (8.4% vs. 4.3%; p = .55), single hop (7.4% vs. 9.3%; p = .65), or triple hop (6.0% vs. 7.1%; p = .77) between the two groups. Univariate analysis showed significant greater deficits at 9 months in the FNB with respect to slow isokinetic flexion strength (9.6% vs. 0.4%; p = .01). There were no differences in fast isokinetic flexion (-0.2% vs. 0.7%; p = .87) and fast isokinetic extension (6.0% vs. 2.7%; p = .51) strength deficits between the groups. There were clinically relevant greater deficits in the FNB group with respect to slow isokinetic extension (17.3% vs -14.0%, p = .19), but this did not reach statistical significance. With respect to function, there were no differences in deficits for vertical jump (5.2% vs. 6.5%, p = .85), single hop (7.7% vs. 6.2%; p = .79), or triple hop (1.9% vs. 3.9%; p = .35) between the two groups. Conclusion Because previous studies have shown a significant delay in return of strength with FNB, ACB began to be employed at our center for post-operative pain control following ACLR in pediatric and adolescent patients. This study showed that pediatric and adolescent patients treated with FNB as a method of post-operative analgesia after ACLR had significantly greater deficits in fast isokinetic flexion at 6 months and slow isokinetic flexion at 9 months compared to those who received ACB. These differences may or may not have clear clinical relevance. However, patients treated with FNB showed clinically relevant greater deficits in slow isokinetic extension strength at 6 and 9 months postoperatively compared to those who received ACB if 85% strength return is used as criteria to return to sport. Pediatric and adolescent patients could benefit from undergoing perioperative analgesia with ACB instead of FNB, but comparison between these two methods of regional anesthesia may require a prospective trial. Level of Evidence Retrospective cohort study, Level IV [Table: see text][Table: see text]

PARTIAL TRANSPHYSEAL ANTERIOR CRUCIATE LIGAMENT RECONSTRUCTION: CLINICAL, FUNCTIONAL, AND RADIOGRAPHIC OUTCOMES

BACKGROUND Partial transphyseal anterior cruciate ligament (ACL) reconstruction is a technique utilized in the skeletally immature population. The femoral tunnel is placed in the distal femoral epiphysis whereas the tibial tunnel is placed in a transphyseal fashion medial to the tibial tubercle. This technique was introduced in an effort to lessen insult to the distal femoral physis of skeletally immature adolescents while also avoiding the technical difficulty of placing an intra-epiphyseal tunnel in the proximal tibia which at times can be non-anatomic. There is limited literature examining this technique. In this study we analyzed the concurrent surgical procedures, re-operation and graft failure rates, and radiographic outcomes in adolescents undergoing partial transphyseal ACL reconstruction. METHODS Consecutive patients undergoing partial transphyseal ACL reconstruction by the two senior authors (NP and CA) were retrospectively reviewed. Inclusion criteria consisted of patients with symptomatic ACL rupture with open distal femoral physes and at least two years of growth remaining by chronologic and physiologic age as determined by growth and pubertal history. All patients received hamstring autograft. Femoral tunnels were drilled in an intra-epiphyseal location utilizing small angle guides under fluoroscopic guidance. Transphyseal tibial tunnels were drilled in standard fashion with a tip-aiming guide while minimizing thermal damage from slow reaming, avoiding horizontal tunnel placement, and using extraphyseal graft fixation to lessen insult to the proximal tibial physis. Radiographic outcomes including bilateral limb length (LL) and alignment as judged by mechanical axis deviation (MAD), mechanical lateral distal femoral angle (mLDFA), and medial proximal tibial angle (MPTA) were measured on long standing anterior-to-posterior (AP) view radiographs. Growth disturbance was defined as = 1 cm leg length discrepancy, = 1 cm difference in MAD, or 5-degree difference in mLDFA or MPTA as compared to the non-operative side and MAD/mLDFA/MPTA outside of established range of normal values. Clinical outcomes including graft failure and need for repeat operation were recorded at each follow-up visit. Operative extremity alignment measurements were compared to non-operative extremity measurements utilizing a paired students t-test. RESULTS Twenty-four patients with average follow up of 31.5 ± 17.1 months met inclusion criteria for this study. Five female and 19 male patients were enrolled consisting of 13 left and 11 right knees. Average age at time of surgery was 12.3 ± 0.9 years (10.1-13.8 years). The average ACL graft size was 7.8 mm ± 0.5 mm (6-9 mm). Ten patients (41.7%) had concurrent meniscal surgery, with seven (29.2%) undergoing partial lateral meniscectomy, two (8.3%) lateral meniscus repairs, and one patient (4.2%) with medial and lateral meniscal repairs. Six patients (25.0%) required re-operation at an average of 29.2 ± 17.3 months (1.5-49.5 months) for removal of hardware (n=3), revision ACL reconstruction (n=2), and meniscus surgery (n=1). Two patients had ACL graft failure (8.3%) during sporting activity and underwent revision ACL reconstruction at 19.7 months and 49.5 months post-operatively. There were no contralateral ACL tears. As shown in Table 1, comparison of the mean alignment and limb length measurements between all patients’ operative to nonoperative extremity revealed no significant difference in femur length, MAD, MLDFA, or MPTA. There was a small but statistically significant difference in operative versus non-operative tibia length (390.2 cm versus 392.4 cm, p=0.0004) and limb length (880.9 cm versus 884.0 cm, p=0.02). In analyzing individual patients’ limb length or alignment differences, five patients (20.8%) were identified with a growth disturbance. One patient had isolated shortening of the operative extremity, two with significant lateral deviation of the MAD, and two with both shortening and lateral MAD translation. No patients had significant side-to-side difference in mLDFA or MPTA. Femoral shortening accounted for the majority of the limb length discrepancy in two of the three patients with significant limb length discrepancy. All patients returned to sport. CONCLUSIONS / SIGNIFICANCE Partial transphyseal ACL reconstruction has a 25.0% re-operation rate, most often for hardware removal, and an 8.3% graft failure rate. Overall, approximately 20% of patients undergoing partial transphyseal ACL reconstruction had a growth disturbance but none required surgical intervention for these disturbances. While the partial transphyseal technique spares the distal femoral physis, femur-dominant limb length discrepancy can still occur. Drilling and graft placement across the tibial physis appears to be safe. Further studies are needed to directly compare the radiographic, functional, and clinical outcomes of partial transphyseal ACL reconstruction with transphyseal and all-epiphyseal techniques in the pediatric population. [Table: see text]

The Impact of Transphyseal Anterior Cruciate Ligament Reconstruction on Lower Extremity Growth and Alignment

To evaluate the effect of transphyseal anterior cruciate ligament (ACL) reconstruction on lower extremity radiographic growth and alignment. We retrospectively reviewed patients who underwent transphyseal ACL reconstruction and were followed to skeletal maturity or at least 2years, with the nonoperative limb used as an internal control. Changes in coronal plane alignments and tibial slope of the operative limb were compared with a Wilcoxon test. Associations among sex, tunnel, and graft characteristics and failure; changes in coronal plane measures and tunnel size; and tunnel angles and the development of deformity were examined by χ-square and correlation coefficients. Fifty-nine patients (41 boys and 18 girls) underwent surgery at a mean age of 12.5years (range, 6.8-16.0years). There were differences in changes in the mechanical lateral distal femoral angle comparing operative and nonoperative limbs (decreased 1.1° in girls and 1.9° in boys ≤13years of age, P= .0008 and .025, respectively) and in changes in tibial slope of the operative limb (decreased 2.1° in male patients >13years, P= .012). No patient developed a new limb length difference >1cm. Two boys were treated for deformities. Eight additional patients developed >5° difference in alignment for a rate of radiologic deformity of 10 of 59 or 17%. Neither graft failure nor the presence of deformity was associated with sex, tunnel size, mode of femoral tunnel positioning, inclination of tunnels, or the use of allograft. Radiographically evident limb deformities following transphyseal ACL reconstruction occurred at a rate of 17%, although these deformities were clinically evident in only 5% of patients. Tunnels intersecting physes near cortical margins may increase the risk of developing deformity. Regular follow-up should include alignment radiographs to detect deformities despite the clinical appearance of neutral limb alignment. Level III, case-control study.

The reliability of full-length lower limb radiographic alignment measurements in skeletally immature youth.

PurposeReliable radiographic measurement techniques are important for investigating limb alignments prior to and following paediatric anterior cruciate ligament (ACL) reconstruction. We investigated the inter- and intraobserver reliability of alignment measurements from lower extremity anteroposterior and lateral radiographs of adolescents having undergone transphyseal ACL reconstructionMethodsA total of 15 of 90 patients who had undergone transphyseal ACL reconstruction were randomly selected for alignment measurements of radiographs of operative and nonoperative limbs. Radiographs were de-identified, randomized to three varying sequences and made available in electronic format to three blinded investigators: a junior orthopaedic resident, a senior orthopaedic resident and a paediatric orthopaedic attending. Coronal measurements comprised the mechanical lateral distal femoral angle (mLDFA), mechanical medial proximal tibial angle (mMPTA) and mechanical axis deviation (MAD), measured from standing teleoroentgenograms of the lower extremities. Tibial slope was measured on lateral knee radiographs of operative limbs. The intra-class correlation coefficient (ICC) was calculated for each of the three coronal measures and for tibial slope.ResultsIntraobserver reliability was excellent across all measures (ICC > 0.75) except for tibial slope in one investigator’s measurements (good or ICC = 0.68 for the operative limbs) and mLDFA in another investigator’s measurements (fair or ICC = 0.49 for the operative limbs, and poor ICC = 0.27 for the nonoperative limbs). Interobserver reliability was excellent across all investigators for all measurements for operative and nonoperative limbs.ConclusionsRadiographic measurements of lower extremity alignment may be reliably measured on teleoroentgenograms in a subset of youth who underwent transphyseal ACL reconstruction.Level of EvidenceIII

Primary Allograft ACL Reconstruction in Skeletally Immature Patients-A Systematic Review of Surgical Techniques, Outcomes, and Complications.

The purpose of this systematic review is to ascertain the risk profile of allografts in primary anterior cruciate ligament reconstruction (ACLR) of skeletally immature patients. Three databases (PubMed, EMBASE, and MEDLINE) were searched for articles addressing primary ACLR in skeletally immature patients (i.e., open femoral and tibial physes). Inclusion criteria encompassed the use of allograft tissue with available postoperative outcomes data. The methodological index for non-randomized studies (MINORS) was used to assess all studies. Descriptive statistics such as means, 95% confidence intervals and standard deviations are presented where applicable. A total of 3,852 studies were screened, with 9 studies of a total of 406 skeletally immature patients (mean age 14.9 ± 1.2 years) satisfying inclusion criteria. The majority (98%) of included patients underwent complete transphyseal ACLR. Where specified, allograft options included Achilles tendon (AT) (66.5%), tibialis anterior tendon (7.6%), bone-patellar tendon (2.5%), and fascia lata (1.0%). The use of a bone block for the AT was reported in one patient (0.2%). Postoperatively, and where specified, patients achieved full range of motion (12.1%), had good Lysholm scores of 94 to 100 (8.1%), and a return to preinjury level athletic participation of 82.9% (8.4%). Complications (13.3%) included graft failures (7.9%), nonrevision reoperation (4.7%), and a combined leg length discrepancy and angular (valgus and extension) deformity (0.2%). There were no reported incidences of disease transmission. Although failure rates of primary allograft ACL reconstruction are acceptable compared with other studies of mainly autograft use in this young, high-risk population, there was a very low rate of clinically significant physeal damage. However, the relatively low quality of the included studies limits the ability to recommend routine use of allograft for ACLR in the skeletally immature patient. More robust studies with long-term follow-up data are necessary to better ascertain the influence of allograft choice on postoperative outcomes for these young patients. This is a Level IV study, systematic review of Levels III and IV studies.

The outcome of anterior cruciate ligament reconstruction in skeletally immature patients with transphyseal tunnels

Objective To evaluate the clinical outcomes after transphyseal anterior cruciate ligament (ACL) reconstruction with hamstring autograft in skeletally immature patients. Methods Ten skeletally immature pubescent patients (10 knees) with a mean age of 13.4 years underwent transphyseal ACL reconstruction with hamstring autograft between May 2004 and March 2012. There were 5 males and 5 females. The average duration from injury to surgery was 5.3 months (range 1-12 months). Arthroscopy confirmed ACL rupture in ten knees. Concurrent meniscal surgery was performed in 5 knees. The surgery was conducted via arthroscopically assisted transphyseal reconstruction of the ACL with use of an autogenous quadrupled hamstring tendon graft and fixation devices that do not cross the physes. A protective knee brace was used for 3 months postoperatively with motion limits for the first 2 weeks. The follow-up duration was 6.7 years (range 3-12 years), with evaluation for the following outcomes: physical examination, namely KT-2000 measurements and functional outcome instruments (the International Knee Documentation Committee subjective knee form, the Lysholm scoring, and the Tegner knee activity scale). Radiographs were performed for asymmetrical physeal closure, growth arrest lines and leg-length measurements. Results At the latest follow-up, the mean 2000 IKDC score improved from preoperative 75.1±5.1 to 93.3±3.0, the mean Lysholm score from preoperative 66.1±8.2 to 94.8±3.6 and the mean Tegner score from 4.4±0.8 to 8.5±0.7. All these outcomes had statistically significant difference. Lachman and pivot-shift testing were weekly positive in 3 knees and negative in 7 knees. The mean range of motion of the knee was 140°. Compared with the contralateral knee, no restriction in knee range of motion of 5° or greater was observed in any patient. All patients had normal range of motion. The mean KT-2000 manual maximum side-to-side difference was 1.5±0.7 mm, while that in 3 patients was greater than 2 mm but smaller than 3 mm. No angular deformities were reported. All leg-length measurements were symmetric bilaterally on clinical examination. The mean lateral distal femoral angle was 87.4°±0.6°, and the mean medial proximal tibial angle was 88.3°±0.7°. No patients reported traumatic graft disruption or underwent revision ACL reconstruction, whereas meniscus injury occurred in 3 patients. Conclusion Transphyseal ACL reconstruction with autogenous quadrupled hamstring graft in treating skeletally immature pubescent patients yields satisfied functional outcomes without growth disturbance at a mean follow-up of 6.7 years. Key words: Anterior cruciate ligament; Wounds and injuries; Anterior cruciate ligament reconstruction; Adolescent; Growth plate

Magnetic Resonance Imaging Evaluation of Physeal Violation in Adolescents After Transphyseal Anterior Cruciate Ligament Reconstruction

To quantify and compare the amount and location of physis violation of the distal femur and proximal tibia after transphyseal anterior cruciate ligament (ACL) reconstruction in skeletally immature patients. This study included 19 patients with open physes of the distal femur and proximal tibia who underwent ACL reconstruction with tibialis anterior allografts. Physeal tunnel volume and location on the growth plate, as well as obliquity to the growth plate, were measured by 3-dimensional postoperative magnetic resonance imaging of the distal femur and proximal tibia. The percentage of physeal violation (ratio of the tunnel to the entire growth plate area) was similar for the distal femur and proximal tibia (3.95% vs 3.65%, P= .582). There were no differences in tunnel obliquity to the growth plate in the coronal (56.1° vs 71.6°, P= .061) and sagittal (85.9° vs 74.9°, P= .092) planes. The distal femoral tunnel was located 6.2% (17.2% vs 23.4%, P= .001) more peripherally in the anteroposterior direction and 9.7% (27.1% vs 36.8%, P < .001) more peripherally in the mediolateral direction than was the tibial tunnel. The mean percentages of physeal violation of tunnel creation during ACL reconstruction in adolescent patients were 3.95% for the distal femur and 3.65% for the proximal tibia. Moreover, femoral tunnels were located more peripherally on the growth plate than were tibial tunnels, in both the anteroposterior and mediolateral directions. Level IV, case series.

Arthroscopic transphyseal anterior cruciate ligament reconstruction in adolescent athletes.

To evaluate the 5-year outcome of arthroscopic transphyseal anterior cruciate ligament (ACL) reconstruction in 19 adolescent athletes. 14 male and 5 female adolescent athletes aged 12 to 16 (mean, 13.9) years with Tanner stage 2 or 3 open physes underwent arthroscopic transphyseal ACL reconstruction by a single surgeon and were followed up for 5 years. Patients were evaluated using the numerical rating score (NRS) for pain, knee osteoarthritis outcome score (KOOS), International Knee Documentation Committee (IKDC) score, Tegner Activity Scale, and Lysholm Score, as well as the leg length discrepancy, femorotibial alignment, varus or valgus deformities, active and passive knee range of motion. At 5-year follow-up, physes were closed in all patients. The mean NRS for pain improved from 7.2 to 1.6; the KOOS improved from 55.3 to 88; the mean IKDC score improved from 34.5 to 84; the mean Tegner Activity Scale improved from 2.7 to 8.2 and was comparable with that before injury (8.4); and the mean Lysholm score improved from 36.3 to 84.6. All except 2 patients returned to their pre-injury level of sports activity after a mean of 25 weeks. The 2 exceptions had a 2+ Jerk test and a 3+ Lachman test; one of them also had positive signs for a lateral meniscal lesion. Both had sustained a second trauma not long before the 5-year follow-up. Two patients had reduced sensitivity in the anteromedial aspect of the proximal third of the tibia. One patient had leg length discrepancy of +1.5 cm owing to overgrowth response of the physis. Transphyseal ACL reconstruction is a viable option for skeletally immature patients, with high reproducibility, a high rate of return to sport, and a low incidence of growth disturbance. Early surgery can prevent the onset of meniscal lesions and early osteoarthritis.

Functional outcome after transphyseal anterior cruciate ligament reconstruction in young patients with open growth plates

BackgroundThis study evaluates sports ability, rotational laxity and potential growth changes in children after transphyseal ACL reconstruction with metaphyseal fixation technique, considering physis biology by placing drill holes vertically in the femoral anatomic origin in order to reduce volumetric injury to the physis. MethodsIn this retrospective trial of 42 patients data were collected. Thirty-seven were reviewed measuring rotational laxity and anteroposterior tibial translation using the Laxitester (ORTEMA Sport Protection, Markgroeningen, Germany) and the KT1000. Clinical examination was evaluated with the IKDC 2000 knee examination form. Leg axis was determined with digital photography and leg length was assessed clinically. Sports ability was assessed with questionnaires including subjective IKDC, Tegner Activity Scale, Activity Rating Scale and a questionnaire on sports and level of sports. ResultsMean follow-up was 24.9months. Mean age at surgery was 13.2years in boys and 13.1years in girls. IKDC 2000 grading was A or B in 28 patients and C in nine patients. Significant increased anterior tibial translation was observed in neutral position and in external tibia rotation. No growth abnormalities were seen. Fifty-seven percent of the patients were able to participate in competitive sports at follow-up. ConclusionTransphyseal ACL reconstruction with metaphyseal fixation in children with open growth plates can be done with low risk of growth changes. Return to competitive sports is possible although low rotational laxity still exists. Level of evidenceIV.

The Risk of Transphyseal Drilling in Skeletally Immature Patients With Anterior Cruciate Ligament Injury.

Background:Anterior cruciate ligament reconstruction (ACLR) in skeletally immature patients can result in growth plate injury, which can cause growth disturbances.Purpose:To evaluate radiological tibial and femoral length and axis growth disturbances as well as clinical outcomes in skeletally immature ACLR patients treated with a transphyseal drilling technique.Study Design:Cohort study; Level of evidence, 3.Methods:A total of 39 pediatric patients with ACL injury and open physes at time of surgery, as diagnosed clinically and with magnetic resonance imaging (MRI), were treated using transphyseal ACLR using hamstring graft. Mean patient age was 11.7 years (range, 9.0-14.0 years). Patients were evaluated with full extremity radiographs measuring leg length discrepancy and malalignment, as well as clinical evaluation with KT-1000 arthrometer measurements and Tegner activity scale and Knee injury and Osteoarthritis Outcome Score (KOOS) outcomes after follow-up of 68 months (range, 29-148 months).Results:Of the 39 initial patients, 33 were evaluated both clinically and radiographically. We found a mean femoral length shortening of 3.5 mm (P = .01) on the operated leg. Eight patients (24%) had a more than 10-mm shortening of the operated leg, whereas only 1 patient (3%) had a 10-mm shortening of the nonoperated leg. In 27 of 33 patients (82%; P < .001), the anatomic femoral axes of the operated leg were found to be more than 2° of valgus compared with the nonoperated leg. The tibial anatomic axes changed into a less pronounced varus angulation (P = .02). The femoral-tibial anatomic axes were not significantly different when comparing the 2 legs. We did not find any statistical difference in growth arrest comparing patients treated surgically at the ages of 13 to 14 years to patients younger than 13 years. Tegner and KOOS scores were significantly lower among girls compared with boys. Side-to-side KT-1000 arthrometer difference improved from 5.2 mm preoperatively to 1.6 mm at follow-up.Conclusion:This study shows that transphyseal ACLR in children results in minor length growth disturbances in 24% of patients. The surgically induced distal femoral valgus angulation is counterbalanced by a proximal tibial varus angulation. Growth disturbance after surgery is not associated with a certain pediatric age group. Otherwise, transphyseal ACLR has satisfactory clinical outcomes, with good subjective outcomes, function level, and knee stability.

Tibial tunnel defect size as a risk factor in growth arrest following paediatric transphyseal anterior cruciate ligament reconstruction: an anatomical study.

There is ongoing controversy regarding growth disturbances in younger patients undergoing anterior cruciate ligament reconstructions. Animal models have shown that an injury of 7-9% of the physeal area is a risk factor for growth disturbances. A total of 39 magnetic resonance imaging studies of the knee were examined. The proximal tibial physeal area was determined using a calibrated 'region of interest' ligature encompassing the tibial physis in the axial plane. The potential defect left by commonly used drill sizes was calculated as a percentage of the physeal area. A 7-mm drill leaves a mean defect of 1.45% physeal area (range: 1.11-1.89%, SD: 0.28, 95% CI: ±0.09), 8-mm drill leaves a 1.84% mean defect (range: 1.43-2.49%, SD: 0.38, 95% CI: ±0.12) and a 9-mm drill leaves a 2.30% mean defect (range: 1.83-3.19%, SD: 0.58, 95% CI: ±0.17). At 55°, 7-mm drill leaves a mean defect of 1.96% (range: 1.32-2.28%, SD: 0.37, 95% CI: ±0.12), 8-mm drill leaves a mean defect of 2.19% (range: 1.71-2.95%, SD: 0.46, 95% CI: ±0.14) and a 9-mm drill leaves a mean defect of 2.76% (range: 2.16-3.73%, SD: 0.58, 95% CI: ±0.18). There was a statistically significant difference in the tunnel area with a change of drill angle (7-mm drill P = 0.005, 8-mm drill P = 0.001, 9-mm drill P = 0.001). On the basis of this study in the context of animal model and observational evidence, the area of physeal injury using drill tunnels for anterior cruciate ligament reconstruction would not appear to contribute to potential growth disturbances.

Transphyseal ACL Reconstruction in Skeletally Immature Patients: Does Independent Femoral Tunnel Drilling Place the Physis at Greater Risk Compared With Transtibial Drilling?

Background:Most studies examining the safety and efficacy of transphyseal anterior cruciate ligament (ACL) reconstruction for skeletally immature patients utilize transtibial drilling. Independent femoral tunnel drilling may impart a different pattern of distal femoral physeal involvement.Purpose:To radiographically assess differences in distal femoral physeal disruption between transtibial and independent femoral tunnel drilling. We hypothesized that more oblique tunnels associated with independent drilling involve a significantly larger area of physeal disruption compared with vertically oriented tunnels.Study Design:Cross-sectional study; Level of evidence, 3.Methods:We analyzed skeletally immature patients aged between 10 and 15 years who underwent transphyseal ACL reconstruction utilizing an independent femoral tunnel drilling technique between January 1, 2008, and March 31, 2011. These patients were matched with a transtibial technique cohort based on age and sex. Radiographic measurements were recorded from preoperative magnetic resonance imaging and postoperative radiographs.Results:Ten patients in each group were analyzed. There were significant differences between independent drilling and transtibial drilling cohorts in the estimated area of physeal disruption (1.64 vs 0.74 cm2; P < .001), femoral tunnel angles (32.1° vs 72.8°; P < .001), and medial/lateral location of the femoral tunnel (24.2 vs 36.1 mm from lateral cortex; P = .001), respectively. There was a significant inverse correlation between femoral tunnel angle and estimated area of distal femoral physeal disruption (r = –0.8255, P = .003).Conclusion:Femoral tunnels created with an independent tunnel drilling technique disrupt a larger area of the distal femoral physis and create more eccentric tunnels compared with a transtibial technique.Clinical Relevance:As most studies noting the safety of transphyseal ACL reconstruction have utilized a central, vertical femoral tunnel, surgeons should be aware that if an independent femoral tunnel technique is utilized during transphyseal ACL reconstruction, more physeal tissue is at risk and tunnels are more eccentrically placed across the physis when drilling at more horizontal angles. Prior studies have shown that greater physeal involvement and eccentric tunnels may increase the risk of growth disturbance.

Allograft and Autograft Transphyseal Anterior Cruciate Ligament Reconstruction in Skeletally Immature Patients: Outcomes and Complications

The purpose of the study was to evaluate outcomes, graft failure rates, and complications after transphyseal soft-tissue allograft and autograft anterior cruciate ligament (ACL) reconstruction (ACLR) in patients with open growth plates. Twenty-nine skeletally immature athletes (30 knees) with a mean age of 13.9 years (range, 9 to 16 years) underwent transphyseal ACLR (22 with quadrupled hamstring autograft and 8 with tibialis anterior allograft). Of the patients, 5 were Tanner stage I, 17 were Tanner stage II, and 7 were Tanner stage III. Outcomes included KT-1000 (MEDmetric, San Diego, CA) measurements and International Knee Documentation Committee (IKDC), Cincinnati, and Lysholm scoring. Radiographs were evaluated for asymmetrical physeal closure, growth arrest lines, and knee alignment. The mean outcomes scores, excluding the 5 graft failures, were 91.8 points for the IKDC score, 93.0 points for the Cincinnati score, and 91.5 points for the Lysholm score at a mean of 4 years' follow-up (range, 24 to 84 months). The 95% confidence intervals for the differences were-27.7 to-18.0 for the IKDC score,-26.4 to-12.1 for the Cincinnati score, and-20.1 to-6.4 for the Lysholm score. One hundred percent of patients ultimately returned to their prior level of sports, but only 76% maintained that level at most recent follow-up. The mean KT-1000 side-to-side difference at most recent follow-up was 0.4 mm (SD, 1.3 mm; range,-2 to 3 mm) (n= 25). Evaluation at a minimum of 2 years postoperatively showed 4 patients with Harris growth arrest lines and 1 genu valgum deformity that spontaneously corrected at latest follow-up. For the remaining 29 knees, there was a mean side-to-side difference of 1.3° (range, 0° to 4°) in the radiographic tibiofemoral angle and 0.2 cm (range, 0 to 1 cm) for clinical leg-length measurements. Sports-related graft failure occurred at a mean of 24 months after ACLR in 16.7% of patients (37.5% with allografts [3 of 8] v 9% with autografts [2 of 22], P= .10). In 5 patients (16.7%), a contralateral ACL injury was sustained. Transphyseal ACLR in patients with open growth plates resulted in a high rate of return to sports with a low rate of growth arrest and deformity at a mean of 4 years' follow-up. Harris growth arrest lines and a case of genu valgum deformity that spontaneously corrected, however, were observed. Graft failure rates and contralateral ACL tears were not insignificant in this young patient population. Level IV, therapeutic case series.

Anterior Cruciate Ligament Reconstruction Using the Transphyseal Technique in Prepubescent Athletes: Midterm, Prospective Evaluation of Results

To evaluate the efficacy, results, and complications of transphyseal technique of anterior cruciate ligament (ACL) reconstruction in prepubertal patients and to assess a possible influence of children's growth on the outcome. Between 2005 and 2009, 22 (16 boys and 6 girls) prepubescent patients, Tanner stage 1 and 2, underwent ACL reconstruction and the follow-up 6, 12, and 24months after surgery and after growth plate closure. The average age of the girls was 11.2years, and of the boys, 12.3years. The average follow-up period was 77.2months. Clinical outcome was evaluated by Lysholm, Tegner, and International Knee Documentation Committee (IKDC) objective and subjective knee scores. Standard radiograms were performed for potential axial growing disturbance. The average follow-up period was 77.2months (range, 54 to 102months), and IKDC subjective scores changed from 58 (range, 44 to 69) before surgery to 87 (range, 86 to 87; P= .00) at 6months, 93 (range, 88 to 97; P= .00) at 12months, and 95 (range, 92 to-98; P= .5) at final examination. Lysholm score increased from 58 (range, 53 to 64) before surgery to 89 (range, 85 to 92; P= .00) at 6months and 96 (range, 94 to 100; P= .00) at 12months, 24months (P= .9), and final examination (P= .8). Before injury, all patients were graded 7 on the Tegner scale. Nineteen athletes reached at least grade 7 and returned to the level of activity a meanof 9months after the surgery. No patient had deformity or growth disturbances observed clinically. Arthroscopic-assisted transphyseal ACL reconstruction in prepubescent patient is a promising technique, provided that all technical details are respected. It gives excellent subjective and objective knee scores and provides a very good function of the knee joint in the midterm period with no or only minor effect on the leg length. The rate of growth after surgery did not influence the results. Level IV, therapeutic case series.

Intraarticular hamstring graft diameter decreases with continuing knee growth after ACL reconstruction with open physes.

To evaluate the graft diameter size after one-year follow-up or more of patients Tanner II, III, and IV who were submitted to anterior cruciate ligament reconstruction. Ten patients [five males (mean age: 14.4 years) and five females (mean age: 13.6 years)] with open physis and anterior cruciate ligament tear were submitted to transphyseal anterior cruciate ligament reconstruction with quadruple hamstrings graft. During the procedure, graft and tunnel size were recorded. After last clinical follow-up (range 1-11 years), an MRI study was requested and their measurements near the tibial tunnel were compared with the graft diameter measured and used during primary procedure. Four patients had Tanner stage II, four patients Tanner stage III, and two Tanner IV. There were statistically significant decreases in the quadruple hamstrings graft diameter size (average of 25.3%). Mean size at time of surgery was 7.9 mm (±0.87), and mean size measured at different points of follow-up evaluation was 5.9 mm (±0.65). Diameter size of hamstring graft in skeletally immature patients is smaller in most cases. If there is a decrease in the diameter of the graft along postoperative time, the risk of a re-rupture is theoretically further increased. Quadruple hamstring graft decreases a mean 25.3% in diameter from time of anterior cruciate ligament reconstruction surgery until reassessment period in skeletally immature patients. IV.

Functional Movement Competency and Dynamic Balance After Anterior Cruciate Ligament Reconstruction in Adolescent Patients.

Adolescent patients undergoing anterior cruciate ligament (ACL) reconstruction may not adequately recover safe movement patterns before returning to sport participation. The aims of this study were to assess functional movement and dynamic balance 9 months after primary ACL reconstruction in adolescent patients, and to assess for any maturity-specific differences that may guide rehabilitation strategies. A series of 39 adolescent patients who underwent primary, anatomic, transphyseal ACL reconstruction using hamstrings autograft from October 2009 to January 2013 were identified from a research database: 17 skeletally immature (SI) patients (mean age 13.6±1.6 y) and 22 skeletally mature (SM) patients (mean age 16.6±1.2 y). An adult reference population of 16 primary ACL reconstruction patients (mean age 27.4±4.0 y) was also identified. All patients followed a standardized operative and rehabilitation protocol. The 3 patient groups were compared 9 months postoperatively using the Functional Movement Screen (FMS) to assess movement competency and the Lower Quarter Y-Balance Test (LQYBT) to assess single-limb dynamic balance. Nine months postoperatively, the FMS scores for all 3 groups indicated an increased risk for lower extremity injury (total score ≤14). With respect to specific movement patterns, the SI group displayed inferior active straight leg raise score (P=0.006) despite a lower incidence of pain with this movement. With the LQYBT, there was no significant difference in mean anterior (P=0.987), posterolateral (P=0.349), or posteromedial (P=0.870) reach asymmetry between the 3 groups; however, the adolescent groups demonstrated wider ranges of anterior reach asymmetry than the adult group indicating an increased risk for injury. Adolescent patients undergoing primary ACL reconstruction do not consistently recover adequate functional movement patterns by 9 months postoperatively to permit a safe return to sport. We have identified unique functional movement deficits in SI and SM adolescents, which highlight the need for maturity-specific rehabilitation strategies for adolescent patients undergoing ACL reconstruction. Level IV—retrospective cohort

Articular Sinus Tract with Mycobacterium fortuitum Osteomyelitis After Anterior Cruciate Ligament Reconstruction: A Case Report.

Three weeks after transphyseal anterior cruciate ligament reconstruction with a hamstring autograft, a fourteen-year-old boy presented with fevers, joint effusion, and elevated inflammatory markers. Cultures from an operative debridement grew Mycobacterium fortuitum, for which he received six months of antibiotics. Continued drainage prompted magnetic resonance imaging, which revealed osteomyelitis of the tibial tunnel. This case report describes a postoperative infection with an atypical organism that had a protracted course despite early diagnosis. Complete resolution was achieved following tibial tunnel debridement with a high-speed burr and bone-grafting with an antibiotic-laden allograft.

Femoral Nerve Block Is Associated With Persistent Strength Deficits at 6 Months After Anterior Cruciate Ligament Reconstruction in Pediatric and Adolescent Patients

Background: Femoral nerve block (FNB) has become a popular method of postoperative analgesia for anterior cruciate ligament (ACL) reconstruction in pediatric and adolescent patients. Successful rehabilitation after surgery involves return of quadriceps and hamstring strength. Purpose: To compare knee strength and function 6 months after ACL reconstruction in pediatric and adolescent patients who received FNB versus patients with no nerve block. Study Design: Cohort study; Level of evidence, 3. Methods: Patients 18 years or younger who underwent primary ACL reconstruction between 2000 and 2010 at a single institution were identified. If the patient was skeletally immature, a transphyseal ACL reconstruction was performed. Of these patients, 68% underwent reconstruction with a patellar tendon autograft, and in 32% of patients a hamstring autograft was utilized. There were 124 patients who met the study inclusion criteria, including 62 in the FNB group (31 males, 31 females) and 62 patients in the control group (25 males, 37 females). All study patients participated in a comprehensive rehabilitation program that included isokinetic strength and functional testing at 6 months postoperatively. Results: Univariate analysis showed a significantly higher deficit at 6 months in the FNB group with respect to fast isokinetic extension strength (17.6% vs 11.2%; P = .01) as well as fast (9.9% vs 5.7%; P = .04) and slow (13.0% vs 8.5%; P = .03) isokinetic flexion strength. There was no difference in slow isokinetic extension strength deficit between the 2 groups (FNB, 22.3% vs control, 18.7%; P = .20). With respect to function, there were no differences in deficit for vertical jump (FNB, 9.4% vs control, 11.3%; P = .30), single hop (7.6% vs 7.5%; P = .96), or triple hop (8.0% vs 6.6%; P = .34) between the 2 groups. A significantly higher percentage of patients in the control group met functional and isokinetic criteria for return to sports at 6 months (90.2% vs 67.7%; odds ratio, 4.37; P = .002). Conclusion: Pediatric and adolescent patients treated with FNB for postoperative analgesia after ACL reconstruction had significant isokinetic deficits in knee extension and flexion strength at 6 months when compared with patients who did not receive a nerve block. Patients without a block were 4 times more likely to meet criteria for clearance to return to sports at 6 months.

Transphyseal Anterior Cruciate Ligament Reconstruction in Patients With Open Physes

Background: The treatment of anterior cruciate ligament (ACL) injuries in skeletally immature patients is controversial. Current evidence supports the view that surgical techniques restore knee stability and prevent progressive articular damage. However, most of the studies on this topic are small case series or they have short- or medium-term follow-up times. Purpose: To determine the long-term functional outcomes and secondary complications of transphyseal intra-articular ACL reconstruction with hamstring graft in skeletally immature patients. Study Design: Case series; Level of evidence, 4. Methods: Transphyseal ACL reconstruction with autograft hamstrings was performed in 27 skeletally immature patients. The average age at surgery was 13 years (range, 12-16 years), and the average follow-up time was 10.6 years (range, 10-13 years). Clinical outcomes were assessed with preoperative and final follow-up Tegner, International Knee Documentation Committee (IKDC) subjective, and Lysholm scores. Surgery details, return to sports, and ACL reconstruction failures were collected. The anteroposterior knee laxity was assessed by arthrometry, and the presence of deformities and lower limb length discrepancies were evaluated by radiographs. The presence of degenerative signs on anteroposterior and lateral knee radiographs at final follow-up was also evaluated. Results: Transphyseal ACL reconstruction was performed with vertically oriented tunnels, 7 to 10 mm in diameter, using semitendinosus-gracilis autograft. The average preoperative Tegner, IKDC, and Lysholm scores were 7, 55, and 40, respectively. Significant differences in these scores were observed at the time of the final assessment (Tegner, 6 [P = .026]; IKDC, 94 [P < .001]; Lysholm, 92 [P < .001]). Two patients reported instability during sports activity. Three patients had a rupture of the ACL graft. No leg length discrepancy, axis malalignment, or degenerative changes were observed. Conclusion: The transphyseal ACL reconstruction in skeletally immature patients is a safe option, with high functional and satisfaction results, without significant growth plate damage in this series of patients.