Isolierter Bündelersatz bei Partialruptur des vorderen Kreuzbandes

Objective

Partial augmentation of isolated tears of the anteromedial and posterolateral bundle of the anterior cruciate ligament (ACL) with autologous hamstring tendons. The intact fibers of the ACL are preserved.

Indications

Symptomatic isolated tear of the anteromedial or posteromedial bundle of the ACL or rotational instability after ACL reconstruction with malplaced tunnels (e.g., high femoral position)

Contraindications

In revision cases: loss of motion due to malplaced ACL and excessive tunnel widening of the present tunnels with the risk of tunnel confluence.

Surgical technique

Examination of anterior–posterior translation and rotational instability under anesthesia. Diagnostic arthroscopy, repetition of the clinical examination under direct visualization of the ACL, meticulous probing of the functional bundles. Resection of ligament remnants, preparation/preservation of the femoral and tibial footprint. Harvesting one of the hamstring tendons, graft preparation. Positioning of a 2.4 mm K-wire in the anatomic center of the femoral anteromedial/posterolateral bundle insertion, cannulated drilling according to the graft diameter. Positioning of a 2.4 mm K-wire balanced according to the femoral tunnel at the tibia, cannulated drilling. Insertion of the graft and fixation.

Postoperative management

Analogous to that for ACL reconstruction.     

Effect of PEEK polymer on tunnel widening after hamstring ACL reconstruction

The purpose of this study was to evaluate the effect of the AperFix device (Cayenne Medical, Inc, Scottsdale, Arizona), composed of polyetheretherketone (PEEK) polymer, on tunnel widening after hamstring anterior cruciate ligament (ACL) reconstruction as compared with 2 other fixation devices: the TransFix (Arthrex, Inc, Naples, Florida) and the EndoButton (Smith & Nephew Endoscopy, Mansfield, Massachusetts). Sixty-seven patients with isolated total ACL ruptures who underwent arthroscopically assisted reconstruction using hamstring autografts at the authors' institution were included in the study. Patients were assigned into 1 of 3 groups in a nonrandomized fashion: AperFix (n=18), TransFix (n=29), and EndoButton (n=20). Mean follow-up was 30 months. Tunnel widening measurements were performed on anteroposterior and lateral digital plain radiographs taken in postoperative week 1 and at final follow-up. Laxity testing, Lysholm scoring, and arthrometric evaluation were performed.All 3 graft fixation devices resulted in significant tunnel widening in both tibial and femoral tunnels at final follow-up when compared with the immediate postoperative period. Tunnel widening between groups was not significantly different in terms of coronal and sagittal femoral tunnel diameters. Tibial tunnel diameter increase in the sagittal plane in the EndoButton group was significantly smaller than that in the TransFix and AperFix groups. No correlation was found between the amount of tunnel enlargement and clinical outcomes of ACL surgery. This study's findings suggest that tunnel enlargement after ACL reconstruction is influenced by the type of graft fixation on the tibial side irrespective of clinical outcome, and PEEK polymer does not have an effect on tunnel widening after hamstring ACL reconstruction.     

前交叉韧带重建术后骨隧道扩大的产生及转归的MRI随访结果

目的 观察前交叉韧带重建术后骨隧道扩大的发生及随时间的演变。方法 对58例（58膝）接受自体胭绳肌腱移植、挤压螺钉固定的前交叉韧带重建病例进行了2年随访。于术后1、3、6、12和24个月分别进行患肢MRI检查,测量矢状位股骨隧道和胫骨隧道的宽度并与术后1个月数值进行比较,增宽≥2mm为隧道扩大。记录骨隧道扩大出现的时间及不同时间段隧道宽度的改变。结果9膝（15．5％）出现股骨隧道扩大,12膝（20．7％）出现胫骨隧道扩大。2膝术后3个月内出现扩大,16膝3～6个月出现扩大,3膝6～12个月出现扩大。隧道扩大的病例术后1、3个月隧道宽度比较差异无统计学意义（P〉0．05）,术后6、12、24个月隧道宽度大于1、3个月（P〈0．05）,而6、12和24个月之间隧道宽度比较差异无统计学意义（P〉0．05）。结论 前交叉韧带重建术后骨隧道扩大主要出现于术后3～6个月之间,并在术后12～24个月保持稳定。     

All-Inside Anterior Cruciate Ligament Reconstruction

Anterior cruciate ligament (ACL) reconstruction is one of the most commonly performed knee operations. An “all-inside” technique creates bone sockets for ACL graft passage, as opposed to more traditional full bone tunnels, and typically incorporates suspensory fixation instead of screw fixation to secure the graft. This technique may be indicated for any ACL reconstruction surgery, where adequate bone stock exists to drill sockets and to use cortical fixation. The technique may be used with all soft tissue, as well as bone plug ACL grafts and autograft hamstring or quadriceps tendon; most allograft tendon options may be performed with an all-inside technique. Advantages include anatomic tunnel/socket placement, decreased postoperative pain and swelling, minimal hardware, appropriate graft tensioning and retensioning, and circumferential graft to bone healing. Tips for successful all-inside surgery include matching graft diameter to socket diameter, drilling appropriate length sockets based on individual graft length, so as not to “bottom out” the graft and confirming cortical button fixation intraoperatively. Potential complications include graft-socket mismatch, full-tunnel reaming, and loss of cortical fixation. Multiple studies have shown the all-inside technique to have similar or superior biomechanical properties and clinical outcomes compared to the more traditional full-tunnel ACL reconstruction techniques.     

Tunnel expansion after hamstring anterior cruciate ligament reconstruction with 1-incision EndoButton femoral fixation

Summary: In this study, we compared a study group of 20 patients who underwent anterior cruciate ligament (ACL) reconstruction with hamstring autografts using a 1-incision endoscopic technique verses a control group of 20 patients using a 2-incision technique. The patient groups were compared based on increase of bone tunnel diameter seen radiographically, physical examination, and arthrometer measurements. The 1-incision technique differed from the 2-incision technique in 2 ways: an EndoButton femoral fixation system and drilling of the femoral tunnel through the tibial tunnel (transtibial). This study shows that the majority of tunnel diameter measurements for the 1-incision ACL reconstruction technique were greater than those of the 2-incision ACL reconstruction technique using autologous hamstring tendons, at both 3 and 12 months of follow-up. Between 3 and 12 months follow-up, there was no statistical differences in tunnel enlargement between the 2 groups of patients. The measured tunnel enlargement, therefore, would have occurred before the 3-month follow-up. There was no significant difference in the Lachman or arthrometer testing in either group of patients at the termination of this study. This indicates that, although tunnel expansion is significant, the increased expansion is not related to increased knee laxity in the first year.Arthroscopy: The Journal of Arthroscopic and Related surgery, Vol 16, No 7 (October), 2000: pp 707–714     

前十字韧带双束重建术后CT测量骨隧道大小的价值

目的 探讨前十字韧带(ACL)双束重建术后CT测量骨隧道大小的价值.方法 47例单纯ACL断裂自体胭绳肌腱双束重建患者,男42例,女5例;年龄18～52岁,平均26.8岁.采用双束四隧道八股肌腱重建ACL方法 ,隧道外悬吊式固定.术后分别在X线及CT片上测量胫骨、股骨骨隧道的直径,并与术中钻孔值比较.结果 术中胫骨浅束钻孔直径平均(0.5979±0.0521)cm,胫骨深束钻孔直径平均(0.7479±0.0651)cm,股骨浅束钻孔直径平均(0.5734±0.0487)cm,股骨深束钻孔直径平均(0.6947±0.0732)cm.X线测量结果 示:胫骨浅束直径为0.545±0.762 cm,平均(0.6369±0.0638)em;胫骨深束直径为0.601±0.987 cm,平均(0.7784±0.0841)em;股骨浅束直径为0.534±0.644 cm,平均(0.5780±0.0305)cm;股骨深束直径为0.488～0.817 cm,平均(0.6723±0.0754)cm.CT 测量结果 示:胫骨浅束直径平均(0.6009±0.0502)cm,胫骨深柬直径平均(0.7497±0.0677)cm,股骨浅束直径平均(0.5662±0.0375)cm,股骨深束直径平均(0.7002±0.0709)cm.CT 测量值与术中钻孔值比较差异无统计学意义(P＞0.05).结论 CT 测量方法 可以真实反映胫骨、股骨骨隧道大小,适用于ACL重建术后骨隧道扩大的研究.     

Anterior cruciate ligament reconstruction using semitendinosus and gracilis tendons,bone patellar tendon,or quadriceps tendon-graft with press-fit fixation without hardware. A new and innovative procedure

BONE--PATELLAR TENDON: The "no hardware" technique for ACL reconstruction is a new method that offers many advantages and is straightforward to perform. Its main innovative feature is that it does not require bone-block harvesting from the patella. This reduces donor site morbidity and prevents patellar fractures. The bone tunnels are made using tube harvesters and compaction drilling. This minimizes trauma and obviates the risk of bone necrosis. The articular entrance of the tibial tunnel is completely occupied by the grafts. This prevents a windshield-wiper effect and synovial fluid ingress into the tunnel, and enhances graft incorporation. The fact that no hardware is used with both patellar tendon or hamstring grafts significantly reduces the overall cost of the operation and facilitates revision surgery. The quadriceps tendon is also a very good graft. It is thick and has good biomechanical properties and low donor site morbidity. Its disadvantages are: weakness of quadriceps after the operation, an unsightly scar, and some difficulty in graft harvesting [58]. Also, postoperative MRI is not fraught with the problem of metal artifacts. It is difficult to decide which of the methods currently available for ACL reconstruction is the best because most of them give satisfactory results. In the future, assessments of knee ligament reconstruction techniques should look at long-term stability combined with low complication rates. Ease of revision surgery and low cost should also be taken into consideration, given the large annual volume of knee ligament reconstructions (50,000 in the United States alone) [59]. We believe that our technique addresses most of these issues, and that it constitutes a useful alternative method for ACL reconstruction. SEMITENDINOSUS--GRACILIS: This technique, which was used with 915 patients from June 1998 to February 2002, shows a particularly low rate of postoperative morbidity. The reason is probably to be found in the "waterproofing" of the bone tunnels, which lead to less postoperative bleeding and swelling. No drains were used. Rehabilitation follows the same protocol as used for the reconstruction using patellar tendon grafts (accelerated/functional). As expected, there was no widening of the femoral tunnels and little widening of the tibial tunnels. Interestingly, tibial tunnel enlargement was significantly less in a nonaccelarated rehabilitation group than in the accelerated group [60] without affecting stability. The measured internal torque of the hamstrings, as well as their flexion force, already had returned to normal 12 months postoperatively. In a prospective randomized (unpublished) study comparing this technique with ACL reconstruction with BPT grafts with medial or lateral third with only one bone plug (from the tibial tuberosity, see technique described above), we found no significant difference between both groups in subjective scores, stability, KT-1000 values, Tegner activity score, and IKDC at 1-year follow-up. Only the results of kneeling and knee walking testing were significantly better in the hamstring group [61]. In summary, the advantages of this presented technique are: (1) the knot of the graft is close proximally to the anatomic site of the insertion of the ACL, thus avoiding the Bungee effect.; (2) the press-fit tunnel fixation prevents synovial fluid entering the bone tunnels, windshield-wiper effect, and longitudinal motion within the tunnel; the intensive contact between the bony wall of the tunnel and graft collagen over a long distance without any suture material results in quick and complete graft incorporation; and (3) no fixation material means no hardware problems, facilitates revision surgery, and lowers overall costs.     

In vitro comparison of elongation of the anterior cruciate ligament and single- and dual-tunnel anterior cruciate ligament reconstructions.

This study evaluated strain in the normal anterior cruciate ligament (ACL) and compared it to four different double-strand hamstring tendon reconstructive techniques. Seventeen fresh-frozen knees from 11 cadavers were tested. The strain in the anteromedial and posterolateral bands of the native ACL and their equivalents in four autograft techniques were measured using differential variable reluctance transducers. The anteromedial band of the intact ACL shortened from 0 degree -30 degrees of flexion, then lengthened to 120 degrees; the posterolateral band of the intact ACL shortened from 0 degree - 120 degrees of flexion. Following ACL excision, these knees underwent reconstruction with double-strand hamstring tendons with either single tibial and femoral tunnels, single tibial and dual femoral tunnels, dual tibial and single femoral tunnels, or dual tibial and dual femoral tunnels. With the exception of the dual-band, dual-tunnel technique, all of the procedures placed greater strain on the reconstructive tissues than was observed on the native ACL, after approximately 30 degrees of flexion. These results indicate that dual-band hamstring tendon reconstructions placed with single tibial and femoral tunnels do not address the complexity of the entire ACL. Rather, these procedures appear to only duplicate the effect of the anteromedial band, while perhaps overconstraining the joint as a result of its inability to reproduce the function of the posterolateral band. During rehabilitation following ACL reconstruction, therefore, only from 0 degree - 30 degrees of the graft tissues are not significantly strained. Dual tibial and femoral tunnel techniques should be evaluated further to more closely recreate knee kinematics following ACL reconstruction.     

Bone tunnel enlargement after anterior cruciate ligament reconstruction with semitendinosus tendon using Endobutton fixation on the femoral side

We evaluated 29 knees with a minimum follow-up of 2 years after anterior cruciate ligament (ACL) reconstruction using doubled autogenous semitendinosus tendons. On the femoral side, a 5-mm Mersilene tape (Ethicon, Norderstedt, Germany) with an Endobutton (Acufex Microsurgical, Mansfield, MA) was used. The tendon was fixed on the tibial side with two staples. Regarding the IKDC score, 66% of the patients were graded as normal or nearly normal. The anterior laxity side-to-side difference (KT 1000, man-max-drawer) was under 3 mm in 55% and under 5 mm in 90%. Radiographs taken in the lateral and anteroposterior projections of the knee showed sclerotic bone tunnel margins. The diameter of the bone tunnels were measured, corrected for magnification, then compared with the original reamed diameter to determine any change in size. Enlargement of at least 2 mm was identified in 72% of the femoral tunnels and 38% of the tibial tunnels. No correlation was found concerning the enlargement of the tunnel and the IKDC score or the residual joint laxity. We conclude that using an Endobutton-Mersilene construct in ACL reconstruction leads to femoral and tibial bone tunnel enlargement at follow-up of 2 years. (Arthroscopy 1998 Nov-Dec;14(8):810-5.)     

Revision anterior cruciate ligament reconstruction using a unique bioabsorbable interference screw for malpositioned tunnels

Revision anterior cruciate ligament (ACL) reconstruction surgery has become increasingly common. The number of primary ACL reconstructions increases each year, and athletes are often able to return to cutting and pivoting sports. Most failed ACL reconstructions result from technical errors, commonly malpositioned tunnels. Correcting such tunnels in revision surgery requires understanding anatomy, preoperative planning, and often multiple methods of addressing bony defects. Multiple options have been described for handling these bony deficiencies, many of which are technically difficult and time-consuming to correct. We describe a simple technique for addressing a bony defect during revision ACL reconstruction using a unique bioabsorbable interference screw comprised of an osteoconductive bioceramic beta-tricalcium phosphate and poly(lactide-co-glycolide). Unique properties of this screw provide significant structural support for drilling revision tunnels through a portion of the screw or next to the screw, which allows for uncompromised tunnel placement.     

Technique of anatomical footprint reconstruction of the ACL with oval tunnels and medial portal aimers

Purpose

The purpose of this article was to demonstrate an anterior cruciate ligament (ACL) reconstruction technique using oval tunnels. Aim of this single bundle technique is to fit the footprint anatomy of the ACL as closely as possible.

Technique and patients

The presented technique is a single bundle technique using a semitendinosus graft. For femoral tunnel placement, a specific medial portal aimer (Karl Storz, Tuttlingen, Germany) is used. Aiming and drilling of the femoral tunnel are performed via the medial portal. Oval tunnels are created by stepwise dilatation with ovally shaped dilatators. The position of the femoral tunnel is visualized and controlled with the arthroscope via the medial portal. For the tibial tunnel placement, a specific aimer was used as well. With this technique, 24 patients were operated and all intra- and postoperative complications were analyzed prospectively. The tunnel position was documented postoperatively by CT scan.

Results

There were no significant intra- and postoperative complications associated with the oval tunnel technique. The postoperative 3D CT scan revealed that all femoral and tibial tunnels were located within the area of the anatomical ACL insertions.

Conclusions

This article presents an ACL reconstruction technique using oval dilatators and medial portal aimers to create oval tunnels. These oval tunnels match the insertion site anatomy much closer than round tunnels do.

Level of Evidence

Level IV, case series.     

Anterior cruciate ligament reconstruction in the immature athlete: long-term results of intra-articular reconstruction.

From 1986-1992, a total of 21 ACL reconstructions were completed in 20 skeletally immature athletes with an average age of 13.7 years (range: 11.8-15.6 years). Fifteen patients underwent operative reconstruction with hamstring tendons with wide open physes and 6 patients with bone-patellar tendon-bone (BPTB). All grafts were anatomically placed through transphyseal bone tunnels in the femur and tibia. Nineteen of 20 patients (20 of 21 reconstructions) returned for follow-up at an average of 34 months (range: 17-89 months). All patients had reached skeletal maturity at follow-up. No patient had limb-length discrepancy >1 cm postoperatively. No change in tibiofemoral alignment was noted (average 4.5 versus 4.25, P=.69). Modified Lysholm score was 93/95, and 19 of 20 athletes returned to preinjury level sports activity. Ligament laxity side-to-side difference was <3 mm in 16 patients, 3-6 mm in 2 patients, and >6 mm in 2 patients. One patient developed recurrent symptomatic laxity and was lost to follow-up. Two late graft ruptures (1 hamstring and 1 BPTB graft) occurred after major reinjury during sports. In this group of patients, ACL reconstruction through bone tunnels successfully eliminated instability although the failure rate, including late graft ruptures, was higher than that usually reported for adults. No limb length or angular deformity developed as a result of the transphyseal tunnels.     

ACL Reconstruction Graft Angle and Outcomes: Transtibial vs Anteromedial Reconstruction

Background

The importance of creating an anatomic anterior cruciate ligament (ACL) reconstruction has been receiving significant attention. The best technique by which to achieve this anatomic reconstruction continues to be debated. The two most common methods are the transtibial (TT) and anteromedial (AM) techniques. Each has its advantages and disadvantages, and the literature comparing the two remains uncertain.

Questions/Purposes

In this prospective comparative study, we aimed to compare the ACL graft and tunnel angles achieved using the anatomic transtibial (TT) and anteromedial (AM) techniques; compare the ACL graft and tunnel angles in knees that have undergone ACL reconstruction and knees with intact ACLs; and determine whether differences in the graft or tunnel angle produce differences in clinical outcomes, as measured using both physical exam and patient-reported outcomes, after ACL reconstruction.

Methods

Patients who underwent primary ACL reconstruction with bone–tendon–bone grafts using a TT or AM technique were included. Femoral graft angle (FGA), tibial graft angle (TGA), and sagittal orientation of the reconstructed ACL and contralateral native ACL were measured on post-operative magnetic resonance imaging. Post-operatively, patients underwent measurement of knee stability and completed the Knee Injury and Osteoarthritis Outcome Score (KOOS) survey.

Results

Twenty-nine patients were enrolled (AM group, 14; TT group, 15); at follow-up, KOOS data were available for 26 patients (13 in each group). There were no differences in sagittal ACL graft angle between groups or in comparison with the normal knee. The FGA was more vertical after TT reconstructions; the TGA was comparable between groups. There were no significant differences in 2-year post-operative physical exam measurements or in KOOS scores.

Conclusion

Anatomic ACL angle was restored after reconstruction with both the TT and AM techniques, despite different FGAs. No significant differences in clinical outcome were noted between groups on physical exam or KOOS at 2 years after surgery. These results suggest that TT reconstruction results in a graft position similar to that seen in AM reconstruction and that the location of the intra-articular tunnel aperture matters more than the orientation of the tunnel.

     

Femoral tunnel enlargement after anatomic anterior cruciate ligament reconstruction: Bone-patellar tendon-bone /single rectangular tunnel versus hamstring tendon / double tunnels

Purpose

This study aimed to prospectively compare the femoral tunnel enlargement at the aperture as well as inside the tunnel after anatomic anterior cruciate ligament (ACL) reconstruction with bone-patellar tendon-bone (BTB) graft to that with hamstring tendon (HST) graft.

Anteromedial Portal Technique for Creating the Anterior Cruciate Ligament Femoral Tunnel

There has been a renewed focus on anterior cruciate ligament (ACL) insertional anatomy and its biomechanics. It has been postulated that traditional single-bundle transtibial reconstructions have placed grafts in a less anatomic location relative to the true ACL insertion site. In traditional transtibial techniques, the femoral tunnel is predetermined by the position of the tibial tunnel. It is our belief that achieving the most anatomic position for the graft requires the femoral and tibial tunnels to be drilled independently. Use of the anteromedial portal technique provides us with more flexibility in accurately placing the femoral tunnel in the true ACL insertion site as compared with the transtibial technique. Advantages include anatomic tunnel placement, easy preservation of any remaining ACL fibers when performing ACL augmentation procedures, and flexibility in performing either single- or double-bundle reconstructions in primary or revision settings. This technique is not limited by the choice of graft or fixation and offers the advantage of true parallel screw placement through the same portal as that used for tunnel drilling in the case of interference fixation.     

Double bundle revision of a malplaced single bundle vertical ACL reconstruction: ACL revision surgery using a two femoral tunnel technique

Background  Several factors influence the outcome after ACL reconstruction. One of the most important factors influencing the resulting knee kinematics and subjective instability is femoral tunnel placement. Revision can be necessary if the femoral tunnel is drilled transtibial in the roof of femoral notch (mismatch). Hypothesis  Double bundle reconstruction using two femoral tunnels and one tibial tunnel technique can be used in revision of a primary vertical ACL reconstruction. Study design  Case series (level of evidence III). Methods  ACL revision was performed in five patients complaining instability after primary transtibial ACL reconstruction. Clinical examination, X-ray and CT analysis were performed to evaluate objective knee laxity, tunnel placement and widening. In all patients a technique using two femoral tunnels in a two medial portal technique and one tibial tunnel was used. Patients were reevaluated at a follow up of 24 months. Results  Preoperatively, pivot shift tests were 2+ in three and 1+ in the remaining two patients. Lachman test was found to be positive in all patients (4 patients, 2+ firm endpoint; 1 patient, 2+ soft endpoint). X-rays showed a femoral tunnel position at 11.30 (1 patient) and 12.00 o’clock (4 patients). In one patient significant tibial tunnel enlargement was to be found. At a follow up of 24 months, KT 1000 was <2 mm side to side difference and the pivot shift test was negative in all patients. Conclusion  Revision of a primary vertical ACL reconstruction can be safely performed using a double bundle reconstruction with two femoral tunnels in a two medial portal technique and one tibial tunnel technique. The femoral tunnel need to be located in the anatomic origin of the AM and PL bundle. Clinical relevance  Femoral tunnel placement in the notch of the intercondylar notch should be avoided. In these cases without significant tunnel enlargement, a primary double bundle revision with two femoral and one tibial tunnel can be performed.     

关节镜下LARS人工韧带及4股半腱肌肌腱重建前交叉韧带

目的评价LARS人工韧带和自体4股半腱肌肌腱关节镜下重建膝前交叉韧带（ACL）的临床疗效。方法对28例膝ACL断裂患者行关节镜下ACL重建术,根据重建材料的来源分为LARS人工韧带组（13例）和自体4股半腱肌肌腱组（15例）。采用ACL解剖等长重建技术建立胫骨、股骨骨道。并对两组的关节稳定性和Lysholm膝关节功能评分进行对比研究。结果术后膝关节稳定性LARS人工韧带组优于4股半腱肌肌腱组（P〈0.05）。移植后两组Lyshrolm膝关节功能评分较移植前提高（P〈0.05）。术后6个月LARS人工韧带组Lysholm评分（90.4分±5.3分）高于4股半腱肌肌腱组（81.2分±4.7分）（P〈0.05）。结论在关节镜下重建ACL术中,LARS人工韧带可作为自体材料的良好替代物。     

Effect of compaction drilling during ACL reconstruction with hamstrings on postoperative tunnel widening

Type of study This study investigates whether the amount of tibial and femoral bone tunnel enlargement following anterior cruciate ligament (ACL) reconstruction with hamstrings can be reduced by compaction bone tunnel drilling. Methods Patients undergoing primary ACL reconstruction with four-strand hamstrings (n = 26) were matched to either extraction drilling (n = 13) or compaction drilling (n = 13). Extracortical femoral fixation was by means of a 20 mm Endobutton CL and tibial fixation was by resorbable interference screw. A CT scan was performed on the second postoperative day and an average of 4 months (range 3.8–5 months) postoperatively in all patients. Tunnel enlargement was determined by digitally measuring the widths perpendicular to the long axis of the tunnels on an oblique coronal and axial plane. The CT measurements were compared to the intraoperative drill diameter. Results With extraction drilling the average tibial tunnel diameter proximal to the interference screw increased from 8.5 to 10.4 mm (P < 0.0001) and the average femoral tunnel from 8.0 to 10.6 mm (P < 0.0001). With compaction drilling it increased from 8.2 to 10.0 mm (P < 0.0001) and from 7.6 to 9.7 mm (P < 0.002), respectively. Tunnel widening was 22% on the tibial side for both groups and 33 versus 28% on the femoral side (P = 0.09) for extraction versus compaction drilling. Conclusion There was a significant tibial and femoral tunnel widening on CT an average of only 4 months following ACL reconstruction with hamstrings. Compaction drilling with a stepped router did not prove to reduce the postoperative tunnel widening significantly. Tunnel widening was higher on the femoral side which could be related to the extracortical femoral fixation technique. Level of evidence Level 4. No benefits in any form have been received, or will be received, from a commercial party related directly or indirectly to the subject of this article.     

Rectangular Tunnel Double-Bundle Anterior Cruciate Ligament Reconstruction with Bone–Patellar Tendon–Bone Graft to Mimic Natural Fiber Arrangement

We describe our current technique of anatomic, double-bundle (DB), rectangular tunnel anterior cruciate ligament (ACL) reconstruction with bone–patellar tendon–bone (BPTB) graft. This technique mimics the natural, or anatomic, arrangement of the native ACL fibers. This technique has the following advantages: (1) creation of a DB ACL reconstruction with a single BPTB graft; (2) maximization of graft–tunnel contact area; (3) containment of the tunnel apertures within the anatomic ACL attachment footprint; (4) rotational control of the graft within the tunnels during and after fixation; and (5) preservation of notch anatomy.     

Technical note: Anterior cruciate ligament reconstruction in the presence of an intramedullary femoral nail using anteromedial drilling

AIM To describe an approach to anterior cruciate ligament(ACL) reconstruction using autologous hamstring by drilling via the anteromedial portal in the presence of an intramedullary(IM) femoral nail.METHODS Once preoperative imagining has characterized the proposed location of the femoral tunnel preparations are made to remove all of the hardware(locking bolts and IM nail). A diagnostic arthroscopy is performed in the usual fashion addressing all intra-articular pathology. The ACL remnant and lateral wall soft tissues are removed from the intercondylar, to provide adequate visualization of the ACL footprint. Femoral tunnel placement is performed using a transportal ACL guide with desired offset and the knee flexed to 2.09 rad. The Beath pin is placed through the guide starting at the ACL's anatomic footprint using arthroscopic visualization and/or fluoroscopic guidance. If resistance is met while placing the Beath pin, the arthroscopy should be discontinued and the obstructing hardware should be removed under fluoroscopic guidance. When the Beath pin is successfully placed through the lateral femur, it is overdrilled with a 4.5 mm Endobutton drill. If the Endobutton drill is obstructed, the obstructing hardware should be removed under fluoroscopic guidance. In this case, the obstruction is more likely during Endobutton drilling due to its larger diameter and increased rigidity compared to the Beath pin. The femoral tunnel is then drilled using a best approximation of the graft's outer diameter. We recommend at least 7 mm diameter to minimize the risk of graft failure. Autologous hamstring grafts are generally between 6.8 and 8.6 mm in diameter. After reaming, the knee is flexed to 1.57 rad, the arthroscope placed through the anteromedial portal to confirm the femoral tunnel position, referencing the posterior wall and lateral cortex. For a quadrupled hamstring graft, the gracilis and semitendinosus tendons are then harvested in the standard fashion. The tendons are whip stitched, quadrupled and shaped to match the diameter of the prepared femoral tunnel. If the diameter of the patient's autologous hamstring graft is insufficient to fill the prepared femoral tunnel, the autograft may be supplemented with an allograft. The remainder of the reconstruction is performed according to surgeon preference. RESULTS The presence of retained hardware presents a challenge for surgeons treating patients with knee instability. In cruciate ligament reconstruction, distal femoral and proximal tibial implants hardware may confound tunnel placement, making removal of hardware necessary, unless techniques are adopted to allow for anatomic placement of the graft. CONCLUSION This report demonstrates how the femoral tunnel can be created using the anteromedial portal instead of a transtibial approach for reconstruction of the ACL.