Abstract
Arthroscopic procedures for ruptured anterior cruciate ligament (ACL) tears are a common standard. However, there are strong alternatives to this standard. The purpose of this study is to present a precise, fast, and minimally invasive but open procedure for reconstruction of the ruptured ACL. The torn ACL is substituted by a widely used bone–patellar tendon–bone (BPTB) autograft. After the BPTB graft has been harvested, the Hoffa body is exposed and mobilized ventrally. The surgeon then has a free view of the remnants of the torn ACL, which are to be removed completely. Through the tibial and femoral footprints of the ACL, a tunnel is drilled under a direct view, thus ensuring optimal anatomic positioning of the BPTB graft. The described approach is simple in handling and advantageous because all steps are performed under a direct view, which improves overall precision and intraoperative functional control.
Ruptured anterior cruciate ligaments (ACLs) are among the most common diagnoses of the knee joint—especially in young patients.1 Therefore a broad spectrum of techniques describing treatment options and procedures have been published.2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12 Commonly used methods are based on either a hamstring graft or autograft or a bone-tendon-bone (BTB) autograft.13 However, there is controversy regarding which technique guarantees the best outcome in terms of functionality and stability (including long-term stability) because each technique offers certain advantages and pitfalls.12, 14, 15, 16, 17, 18, 19
One major pitfall is diminished biomechanical functionality due to incorrect positioning of the graft. Therefore we sought to combine certain advantageous features such as a good (direct) view and easy handling. These features are essential for precise insertion of the graft, satisfactory functional results, sustainment of stability, and fast recovery (Table 1, Table 2, Table 3).
Table 1.
Pearls and Pitfalls
| Pearls |
| Precise placement of jig onto tibial footprint |
| Easy to perform ROM control with direct observation of BTB graft |
| Principally femoral fixation could also be achieved with other techniques (EndoButton, interference screw, and so on) |
| Easy to perform drilling of femoral tunnel to defined length |
| Pitfalls |
| Incorrect positioning of femoral cross-pins (e.g., inside tendon instead of bone) |
| Breaking of K-wire because of overbending |
| Washing-out effect and tunnel enlargement |
| Fracture or pull-off of one of the bony ends |
BTB, bone-tendon-bone; ROM, range of motion.
Table 2.
Indications and Contraindications
| Indications |
| Traumatic or degenerative ACL tears in physically active, young, mobile patients |
| Contraindications |
| Limited capability of participating in rehabilitation program |
| Tibial or femoral fracture corresponding with planned insertion tunnel |
| Malpositioned axes of femur and tibia |
ACL, anterior cruciate ligament.
Table 3.
Treatment Algorithm
| 1. Arthroscopic examination |
| 2. Midline skin and fascia incision |
| 3. BTB graft edge marking and drilling of suture thread holes |
| 4. Harvest of BTB graft |
| 5. Mobilization of Hoffa body |
| 6. Removal of ACL remnants |
| 7. Placement of jig |
| 8. Insertion of K-wire through both original footprints of ACL |
| 9. Drilling of insertion tunnel and placement of BTB graft |
| 10. Femoral fixation with cross-pins |
| 11. Tibial fixation with interference screw |
| 12. Wound closure |
ACL, anterior cruciate ligament; BTB, bone-tendon-bone.
Surgical Technique
Patients are anesthetized by spinal anesthesia or, in some cases, by intubation anesthesia and peridural anesthesia. They are then laid in the supine position, allowing the knee to be moved passively over the entire range of motion (ROM).
The affected knee joint is examined arthroscopically to detect—and, if necessary, treat—concomitant injuries such as meniscal lesions or cartilage defects.20 This is performed only if there are typical, suspicious radiologic or clinical signs of further damage.
After the arthroscopic examination, the skin and the underlying fascia are split with a straight midline incision. When the skin incision is started above the distal third of the patella and ends at the tibial tubercle, the patellar ligament is exposed just at the length of the future graft (Fig 1).18 Thereafter the dimensions of the future BTB graft are defined by marking its edges. The BTB graft should have an approximate diameter of 8 to 9 mm (Fig 2). The osseous parts of the patella, as well as of the tibia, should have a length of approximately 20 mm. One hole (0.8 mm) is drilled into each osseous part of the future BTB graft. The surgeon then resects the BTB graft, primarily mobilizing it using a bone cutter and, eventually, levering it with chisels. Through the previously drilled holes, 2 No. 3-0 vinyl sutures are placed to improve the handling of the BTB graft.
Fig 1.
To tighten the patellar tendon, the knee is positioned at 90°. The patellar tendon is exposed, while the skin and fascia are held aside. The desired measurements of the bone-tendon-bone (BTB) graft are marked, and the graft is harvested with a mini-saw (and chisels). To guarantee high tear strength, the BTB graft should be resected following the fiber orientation of the patellar tendon.
Fig 2.
To achieve a good fit, the bone-tendon-bone (BTB) graft is stretched and pulled through a mold with a certain diameter (normally 8 to 9 mm); this will be the diameter of the insertion tunnel as well. In this case a press-fit technique should be avoided because the BTB graft will not pass through the tunnel.
The assisting surgeon simultaneously shapes and smoothes the BTB graft on an extra table. To achieve a good fit, the correct diameter of the BTB graft is controlled using a mold. Meanwhile, the surgeon mobilizes the Hoffa body ventrally (Fig 3). However, it is not completely resected but is only swung out, thus conserving its blood supply. Now, the remnants of the ruptured ACL are exposed and removed completely. A jig (DePuy Mitek, Raynham, MA) is placed onto the tibial footprint of the ACL. In addition to visual control, the correct position can be checked while controlling the ROM to avoid future impingement. Then, a K-wire is inserted, imitating the exact course of the former ACL. The insertion tunnel is drilled in accordance with the diameter of the BTB graft, with the K-wire used as a guide (Fig 4). The tunnel depth on the femoral side should be limited to 20 to 25 mm to guarantee an optimal fit of the graft. Another jig (DePuy Mitek) is placed to prepare the insertion channels for the Rigidfix cross-pins (DePuy Mitek) in the femur.
Fig 3.
After resection of the bone-tendon-bone graft, the Hoffa body (yellow) is mobilized and remnants of the anterior cruciate ligament are removed. A jig (gray) is placed exactly onto the original tibial footprint, and a K-wire (red) is inserted. The K-wire now exactly imitates the course of the former ACL and serves as a guidewire for the further steps.
Fig 4.
The previously placed K-wire guides the drilling of the insertion tunnel. The femoral part of the tunnel corresponds to the length of the osseous end of the bone-tendon-bone graft (approximately 20 mm).
The BTB graft is then attached to the K-wire and pulled into its final position (Fig 5, Fig 6). The insertion channels for the cross-pins are deepened into the osseous part of the BTB graft. The femoral part of the BTB graft is then mounted by placing two 2.7-mm Rigidfix cross-pins in a parallel manner from laterally into the osseous part through the already drilled insertion channels. Again, ROM is tested. To fix the tibial part of the BTB graft, an Absolute Interference screw (DePuy Mitek) is inserted from distally. The joint is again controlled for complete ROM. The Hoffa body is then replaced in its original position. The wound is closed in layers starting with the split patellar ligament (Fig 7). A single injection of gentamicin and tranexamic acid is administered through the patellar ligament. Finally, the skin is closed with single stitches (Video 1), and the sutures and joint are covered with sterile wound dressing.
Fig 5.
The bone-tendon-bone (BTB) graft (orange) is attached to the K-wire that is pulled out through the femur, thus bringing the graft into its position. The indicated jig (gray) is used for femoral fixation of the BTB graft using Rigidfix pins (blue).
Fig 6.
The bone-tendon-bone (BTB) graft is shown in its final position. Before and after final fixation of the tibial part, range of motion is performed to make small adjustments to the tension of the BTB graft if necessary.
Fig 7.
Final position of the bone-tendon-bone (BTB) graft with a double, parallel fixation through Rigidfix cross-pins (blue) on the femoral part and an interference screw on the tibia. Wound closure has already been performed with single stitches.
Technical Considerations
The following technical considerations should be made (Table 1):
-
1.
The restoration of the highly vascularized Hoffa body into its original position maintains proprioception and supports the nutrition of the BTB graft. Therefore the resection edges should be as small as possible.
-
2.
The insertion points and depth of the femoral part of the ligament tunnel are prepared with high precision through the direct sight. This allows easy and quick repositioning of the jig before the placement of the K-wire.
-
3.
For satisfactory functionality, ROM has to be controlled intraoperatively.21 Corrections of the tension can be made by either pulling the tibial component of the BTB graft more distally or pushing it more proximally before fixation. However, for smaller corrections, it may also be sufficient to tighten or loosen the interference screw.
-
4.
If the patient's occupation demands working on his or her knees, refilling of the patellar and tibial defects with cancellous bone is recommended.
-
5.
Although in some cases the previous arthroscopic examination was deemed unnecessary, it is generally recommended to perform such an arthroscopic examination.
Postoperative Treatment
After the operation, the knee joint is mobilized on a continuous passive motion machine and a Cryo/Cuff (DJO, Vista, CA) is provided. However, we apply a knee joint brace with limited flexion of 60° for 4 weeks. Sutures are removed after 10 days. After 4 weeks, patients are encouraged to gain full active ROM. This is accompanied by a physiotherapeutic progression-to-strengthening program that focuses on the isometric reinforcement of the quadriceps.
Discussion
After harvesting of the BTB graft, the only anatomic structure keeping the surgeon from directly accessing the damaged ACL is the Hoffa body. Thus functional mobilization of the Hoffa body seems to be a logical consequence. As a result, our approach represents a fast and secure way to achieve the replacement of the ruptured ACL. Exact placement of the BTB graft in the original position of the ACL is essential for satisfactory functional outcomes because biomechanical demands on the BTB graft only can be met in this way. This approach enhances this principle through the direct sight and the possibility of easy-to-perform ROM control. Although arthroscopic methods can deliver results that are just as exact in terms of graft placement, the process may be exhausting because of awkward handling of arthroscopic devices during ROM control before fixation of the graft. Compared with previously described open approaches, our approach can be considered minimally invasive because the joint is not subluxated nor are the soft tissues—apart from the Hoffa body—more manipulated than in arthroscopic procedures. In our experience, the time to recovery is as fast as that with arthroscopic procedures.
Although no absolute data are yet available, it can be assumed that the described approach is more cost-efficient than arthroscopic methods because the operation time is short (approximately 40 minutes) and cost-intensive arthroscopic surgical devices may not be required. One major advantage is the fast-tracked “de-hospitalization,” which allows daycare hospital treatment or release on the first postoperative day.
The preparation of the tunnel at the tibial site is not yet optimal because the entire volume is not filled out by the BTB graft. This contributes to the phenomenon of tunnel enlargement. Although this may have no impact on the clinical outcome,22 we believe that it procrastinates long-term recovery. However, because this problem also occurs with arthroscopic procedures, it does not represent a specific shortcoming of our technique. Another potential pitfall of this technique is incorrect placement of the cross-pins because of shifting of the jig. In such a case, the cross-pins might not enter the BTB graft properly. To resolve this problem, the surgeon could push the jig tightly into the desired position or optionally change the fixation method (femoral interference screw, EndoButton system [Smith & Nephew Endoscopy, Andover, MA], and so on). If the K-wire becomes bent on insertion, it can break off. Therefore the correct position has to be previously anticipated using the jig. Although a scrupulous surgical technique is of great importance to structural integrity, a successful intervention can only be achieved under a closely supervised physiotherapeutic rehabilitation protocol.
Footnotes
The authors report that they have no conflicts of interest in the authorship and publication of this article.
Supplementary Data
The patient is placed in the supine position, and the affected knee is flexed to 90°. (1) After explorative arthroscopy and consequent treatment of concomitant injuries such as meniscal tears or cartilage lesions, the skin and underlying fascia are incised between the distal pole of the patella and the tibial tubercle. (2) The edges of the bone-tendon-bone (BTB) graft are marked; 2 small holes are drilled in the osseous parts, and the graft is lifted and prepared on an extra table. (3) After removal of the BTB graft, the Hoffa body is mobilized ventrally. (4) The ruptured anterior cruciate ligament (ACL) is exposed and removed completely. (5) By use of a jig, a K-wire is drilled through the original footprints of the former ACL. (6) The K-wire directs the drilling of a 9-mm tunnel. (7) Through the tunnel, another jig is placed to prepare the femoral fixation of the BTB graft with pins. (8) The BTB graft is then brought into its final position. (9) Through the previously drilled insertion channels, pins are inserted to fix the femoral part of the BTB graft. (10) An interference screw is placed from distally into the tibia to fix the BTB graft completely. (11) A Redon drain is inserted, the Hoffa body is pushed back into its original position, and all portals are closed.
References
- 1.Griffin L.Y., Albohm M.J., Arendt E.A. Understanding and preventing noncontact anterior cruciate ligament injuries: A review of the Hunt Valley II meeting, January 2005. Am J Sports Med. 2006;34:1512–1532. doi: 10.1177/0363546506286866. [DOI] [PubMed] [Google Scholar]
- 2.Guglielmetti L., de Paula Leite Cury R., de Oliveira V., de Camargo O., Severino N., de Moraes Barros Fucs P. Anterior cruciate ligament reconstruction: A new cortical suspension device for femoral fixation with transtibial and transportal techniques. J Orthop Surg Res. 2014;9:110. doi: 10.1186/s13018-014-0110-7. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 3.Jones K.G. Reconstruction of the anterior cruciate ligament. A technique using the central one-third of the patellar ligament. J Bone Joint Surg Am. 1963;45:925–932. [PubMed] [Google Scholar]
- 4.Kartus J., Movin T., Karlsson J. Donor-site morbidity and anterior knee problems after anterior cruciate ligament reconstruction using autografts. Arthroscopy. 2001;17:971–980. doi: 10.1053/jars.2001.28979. [DOI] [PubMed] [Google Scholar]
- 5.Lee R.J., Ganley T.J. The 5-strand hamstring graft in anterior cruciate ligament reconstruction. Arthrosc Tech. 2014;3:e627–e631. doi: 10.1016/j.eats.2014.07.002. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 6.Sarzaeem M.M., Najafi F., Razi M., Najafi M.A. ACL reconstruction using bone-patella tendon-bone autograft: Press-fit technique vs. interference screw fixation. Arch Orthop Trauma Surg. 2014;134:955–962. doi: 10.1007/s00402-014-1999-3. [DOI] [PubMed] [Google Scholar]
- 7.Hirzinger C., Tauber M., Korntner S. ACL injuries and stem cell therapy. Arch Orthop Trauma Surg. 2014;134:1573–1578. doi: 10.1007/s00402-014-2060-2. [DOI] [PubMed] [Google Scholar]
- 8.Mahalingam V.D., Behbahani-Nejad N., Ronan E.A. Fresh versus frozen engineered bone-ligament-bone grafts for sheep anterior cruciate ligament repair. Tissue Eng Part C Methods. 2015;21:548–556. doi: 10.1089/ten.tec.2014.0542. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 9.Proffen B.L., Sieker J.T., Murray M.M. Bio-enhanced repair of the anterior cruciate ligament. Arthroscopy. 2015;31:990–997. doi: 10.1016/j.arthro.2014.11.016. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 10.Lenschow S., Schliemann B., Schulze M., Raschke M., Kosters C. Comparison of outside-in and inside-out technique for tibial fixation of a soft-tissue graft in ACL reconstruction using the Shim technique. Arch Orthop Trauma Surg. 2014;134:1293–1299. doi: 10.1007/s00402-014-2029-1. [DOI] [PubMed] [Google Scholar]
- 11.Dawson AG, Hutchison JD, Sutherland AG. Is anterior cruciate reconstruction superior to conservative treatment? J Knee Surg in press, available online 1 December, 2014. doi:10.1055/s-0034-1396017. [DOI] [PubMed]
- 12.Shelbourne K.D., Beck M.B., Gray T. Anterior cruciate ligament reconstruction with contralateral autogenous patellar tendon graft: Evaluation of donor site strength and subjective results. Am J Sports Med. 2015;43:648–653. doi: 10.1177/0363546514560877. [DOI] [PubMed] [Google Scholar]
- 13.Gifstad T., Foss O.A., Engebretsen L. Lower risk of revision with patellar tendon autografts compared with hamstring autografts: A registry study based on 45,998 primary ACL reconstructions in Scandinavia. Am J Sports Med. 2014;42:2319–2328. doi: 10.1177/0363546514548164. [DOI] [PubMed] [Google Scholar]
- 14.Xie X., Liu X., Chen Z., Yu Y., Peng S., Li Q. A meta-analysis of bone-patellar tendon-bone autograft versus four-strand hamstring tendon autograft for anterior cruciate ligament reconstruction. Knee. 2015;22:100–110. doi: 10.1016/j.knee.2014.11.014. [DOI] [PubMed] [Google Scholar]
- 15.Sohn O.J., Lee D.C., Park K.H., Ahn H.S. Comparison of the modified transtibial technique, anteromedial portal technique and outside-in technique in ACL reconstruction. Knee Surg Relat Res. 2014;26:241–248. doi: 10.5792/ksrr.2014.26.4.241. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 16.Slone H.S., Romine S.E., Premkumar A., Xerogeanes J.W. Quadriceps tendon autograft for anterior cruciate ligament reconstruction: A comprehensive review of current literature and systematic review of clinical results. Arthroscopy. 2015;31:541–554. doi: 10.1016/j.arthro.2014.11.010. [DOI] [PubMed] [Google Scholar]
- 17.Andernord D., Desai N., Bjornsson H., Ylander M., Karlsson J., Samuelsson K. Patient predictors of early revision surgery after anterior cruciate ligament reconstruction: A cohort study of 16,930 patients with 2-year follow-up. Am J Sports Med. 2015;43:121–127. doi: 10.1177/0363546514552788. [DOI] [PubMed] [Google Scholar]
- 18.Kartus J., Ejerhed L., Sernert N., Brandsson S., Karlsson J. Comparison of traditional and subcutaneous patellar tendon harvest. A prospective study of donor site-related problems after anterior cruciate ligament reconstruction using different graft harvesting techniques. Am J Sports Med. 2000;28:328–335. doi: 10.1177/03635465000280030801. [DOI] [PubMed] [Google Scholar]
- 19.MARS Group Effect of graft choice on the outcome of revision anterior cruciate ligament reconstruction in the Multicenter ACL Revision Study (MARS) Cohort. Am J Sports Med. 2014;42:2301–2310. doi: 10.1177/0363546514549005. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 20.Cox C.L., Huston L.J., Dunn W.R. Are articular cartilage lesions and meniscus tears predictive of IKDC, KOOS, and Marx activity level outcomes after anterior cruciate ligament reconstruction? A 6-year multicenter cohort study. Am J Sports Med. 2014;42:1058–1067. doi: 10.1177/0363546514525910. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 21.Biggs A., Jenkins W.L., Urch S.E., Shelbourne K.D. Rehabilitation for patients following ACL reconstruction: A knee symmetry model. N Am J Sports Phys Ther. 2009;4:2–12. [PMC free article] [PubMed] [Google Scholar]
- 22.Weber A.E., Delos D., Oltean H.N. Tibial and femoral tunnel changes after ACL reconstruction: A prospective 2-year longitudinal MRI study. Am J Sports Med. 2015;43:1147–1156. doi: 10.1177/0363546515570461. [DOI] [PubMed] [Google Scholar]
Associated Data
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Supplementary Materials
The patient is placed in the supine position, and the affected knee is flexed to 90°. (1) After explorative arthroscopy and consequent treatment of concomitant injuries such as meniscal tears or cartilage lesions, the skin and underlying fascia are incised between the distal pole of the patella and the tibial tubercle. (2) The edges of the bone-tendon-bone (BTB) graft are marked; 2 small holes are drilled in the osseous parts, and the graft is lifted and prepared on an extra table. (3) After removal of the BTB graft, the Hoffa body is mobilized ventrally. (4) The ruptured anterior cruciate ligament (ACL) is exposed and removed completely. (5) By use of a jig, a K-wire is drilled through the original footprints of the former ACL. (6) The K-wire directs the drilling of a 9-mm tunnel. (7) Through the tunnel, another jig is placed to prepare the femoral fixation of the BTB graft with pins. (8) The BTB graft is then brought into its final position. (9) Through the previously drilled insertion channels, pins are inserted to fix the femoral part of the BTB graft. (10) An interference screw is placed from distally into the tibia to fix the BTB graft completely. (11) A Redon drain is inserted, the Hoffa body is pushed back into its original position, and all portals are closed.