Anterior cruciate ligament reconstruction with patellar autograft tendon

There are many techniques, graft choices, and outcome studies evaluating anterior cruciate ligament reconstruction. The current authors specifically look at reconstruction with the patellar tendon from a scientific perspective. Miniopen, endoscopic, and two-incision operative techniques in addition to hamstring versus patellar tendon autograft reconstructions are compared via randomized prospective studies. A review of all studies evaluating arthroscopically-assisted anterior cruciate ligament reconstruction with patellar tendon was conducted. The authors found arthroscopically-assisted anterior cruciate ligament reconstruction to have a high short-term stability rate, extremely high patient satisfaction level, and a low postoperative complication rate. When the endoscopic technique was compared with the two-incision technique, there were no major differences. The difference between patellar tendon and hamstring autograft reconstruction can be described best as subtle, except for the consistent finding of an increased activity level in the patellar tendon group. When the principles of anterior cruciate reconstruction are followed, one can expect consistent results with patellar tendon autograft reconstruction.     

Anterior cruciate ligament reconstruction with hamstring tendons

Reconstruction of the anterior cruciate ligament using hamstring tendons can be successfully accomplished.Semitendinosus and gracilis tendon autografts offer advantages over other commonly used autografts in that they are strong, have stiffness characteristics similar to a normal anterior cruciate ligament, have a large surface area for revascularization, and are adaptable to precise intraarticular positioning. The use of hamstring tendon autografts for anterior cruciate ligament reconstruction avoids the potential surgical morbidity associated with the harvest of autogenous patellar tendon grafts. As with all anterior cruciate ligament reconstructive procedures, attention to detail is essential for a predictable successful outcome, Attention must be paid to graft preparation, tunnel placement, graft fixation and tensioning, and postoperative rehabilitation. When proper attention to detail is performed, restoration of normal anterior laxity with a full range of knee motion can be expected. This technique is particularly applicable in those cases where avoidance of the extensor mechanism is desirable.     

PT-12, a putative ras-activated proliferation-dependent gene, is expressed in patellar tendon and not in anterior cruciate ligament.

We describe a gene (PT-12) that is expressed in the patellar tendon and not in the anterior cruciate ligament. We used a recently developed polymerase chain reaction-based subtractive cDNA analysis to discover genes that are overexpressed in the patellar tendon but not expressed in the anterior cruciate ligament; the long-term objective was to find genes that are central to the self-repair of the patellar tendon, in contrast with the inability of the anterior cruciate ligament to launch a repair response following injury. PT-12 is a homologue of human S2 or mouse LLRep3 ribosomal genes, which are known to be overexpressed in highly proliferating cells. This study opens a new vista to the development of techniques and reagents to study the differences between two periarticular tissues (i.e., the patellar tendon and anterior cruciate ligament) that differ primarily in their ability to self-repair.     

髌腱复合体重建创伤性前后交叉韧带

目的：为了评价髌腱复合体(带骨块的髌韧带，即骨—髌膜—骨)对前后交叉韧带断裂后重建的手术疗效。方法：1995—2001年，收治32例前后交叉韧带损伤的患者给予髌腱复合体重建术。结果：所有病人患膝关节稳定性明显增强，术后抽屉试验全部阴性。结论：带骨块的髌韧带具有强抗牵拉力，固定可靠，等长重建，功能改善明显等优点。髌膜复合体是理想的前后交叉韧带替代材料。     

Anterolateral rotatory instability of the knee. Cadaver study of extraarticular patellar-tendon transposition

A cadaver knee-testing system was used to analyze the effect of an extraarticular reconstruction for anterolateral rotatory instability in which the lateral one third of the patellar tendon with a patellar bone block was transposed to the lateral femoral condyle. Ligament and reconstruction tendon forces were measured using buckle transducers, and joint motion was measured using an instrumented spatial linkage as 90 N anteriorly directed tibial loads were applied to seven knee specimens at 0 degree, 30 degrees, 60 degrees, and 90 degrees of flexion by a pneumatic load apparatus. This was done for each knee with first an intact, then an excised anterior cruciate ligament, and finally the extraarticular reconstruction. Forces in the transposed graft exhibited an isotonic pattern over the flexion range, unlike the intact anterior cruciate ligament, which was more highly loaded in extension than in flexion. The transposition of the patellar tendon led to external rotation of the tibia in both unloaded and anterior load conditions throughout flexion. Collateral ligament forces increased with anterior cruciate ligament excision, with the force in the medial ligament remaining higher than normal with the reconstruction, while the lateral forces became lower than normal.     

Nerve regeneration during patellar tendon autograft remodelling after anterior cruciate ligament reconstruction: An experimental and clinical study

The innervation of the rat and human anterior cruciate ligament, patellar tendon, and patellar tendon autograft after reconstruction of the anterior cruciate ligament was investigated by immunohistochemical and histological methods. A rat model of reconstruction with patellar tendon autograft was evaluated during active graft remodelling (2–16 weeks) and compared with normal ligament and tendon. The knees of 10 patients who had undergone reconstruction with patellar tendon autograft were examined 5–37 months postoperatively (remodelling fully completed) with arthroscopy and biopsy. As a control, biopsies from normal ligament and tendon were obtained from four patients. Nerve fibers were identified using antisera for protein gene product 9.5, a general neural marker. Neuronal regeneration was assessed by the expression of growth-associated protein 43/B-50. The sensory type of innervation was characterized by assessing the distribution of nerves containing the sensory neuropeptides calcitonin gene related peptide and substance P. Immunoreactivity for all neural markers was found in both rat and human anterior cruciate ligament and patellar tendon. Two weeks after reconstruction, the rat autograft was acellular and no innervation could be identified. After 4 weeks, the grafts were viable, and immunoreactivity for protein gene product 9.5, growth associated protein 43/B-50, and calcitonin gene-related peptide was found until the 16th week postoperatively. Immunoreactivity for substance P was found in rat autografts at 4 weeks postoperatively only. All biopsies of human patellar tendon autograft showed signs of the remodelling process being fully completed, with revascularization and a sinusoidal collagen pattern with fibroblast repopulation. Neuropeptide immunoreactivity, however, was not found. The presence of immunoreactivity to sensory neuropeptides in the anterior cruciate ligament and patellar tendon may indicate a nociceptive and neuromodulatory function of these structures. The expression of sensory neuropeptides in the rat patellar tendon autograft suggests a possible involvement of sensory innervation during healing of the graft.     

骨—髌腱—髌前骨膜—肌四头肌腱条骨块嵌入法重建前交叉韧带

为充分有效利用髌腱组织重建前交叉韧带,确保移植关节内段均为髌腱组织,增加移植物的有效长度,同时在关节外矫正前内旋不稳及改进移植物的固定方法,作者设计应用骨－髌腱－髌前骨膜－股四头肌腱条游离移植骨块嵌入法重建ＡＣＬ３８例。术后经平均２年７个月随访,效果良好,优良率８９．７％。     

Simultaneous ipsilateral ruptures of the anterior cruciate ligament and patellar tendon: a case report

The simultaneous diagnosis of ipsilateral patellar tendon rupture and anterior cruciate ligament tear is rare. Surgical repair is complicated by different rehabilitation regimens as well as anterior cruciate ligament graft choices. We present a case where at the same operative setting, the patellar tendon was repaired, and the anterior cruciate ligament reconstructed with autologous hamstring graft.     

Anterolateral rotatory instability of the knee: Cadaver study of extraarticular patellar-tendon transposition

A cadaver knee-testing system was used to analyze the effect of an extraarticular reconstruction for anterolateral rotatory instability in which the lateral one third of the patellar tendon with a patellar bone block was transposed to the lateral femoral condyle. Ligament and reconstruction tendon forces were measured using buckle transducers, and joint motion was measured using an instrumented spatial linkage as 90 N anteriorly directed tibial loads were applied to seven knee specimens at 0°, 30°, 60°, and 90° of flexion by a pneumatic load apparatus. This was done for each knee with first an intact, then an excised anterior cruciate ligament, and finally the extraarticular reconstruction.

Forces in the transposed graft exhibited an isotonic pattern over the flexion range, unlike the intact anterior cruciate ligament, which was more highly loaded in extension than in flexion. The transposition of the patellar tendon led to external rotation of the tibia In both unloaded and anterior load conditions throughout flexion. Collateral ligament forces increased with anterior cruciate ligament excision, with the force in the medial ligament remaining higher than normal with the reconstruction, while the lateral forces became lower than normal.     

Patellar tendon and anterior cruciate ligament have different mitogenic responses to platelet-derived growth factor and transforming growth factor β

The healing responses of the anterior cruciate ligament and the patellar tendon differ markedly. The anterior cruciate ligament fails to heal, whereas the patellar tendon heals slowly. The basis of these differences is unknown. Since cellular proliferation is a critical element of healing, we investigated the response to explants of anterior cruciate ligament and patellar tendon from sheep knees to platelet-derived growth factor-AB and transforming growth factor β1 as a function of time and dose. Explants cultured for 48, 72, and 96 hours with transforming growth factor β1 (0-100 ng/ml) or platelet-derived growth factor-AB (0-200 ng/ml) were radiolabeled for the final 24 hours with [³H]thymidine, and DNA synthesis was quantified as trichloroacetic acid-precipitable radioactivity normalized to dry tissue weight. Statistical analyses (analysis of variance) showed that transforming growth factor β1 induced a significant proliferative response in the anterior cruciate ligament at 96 hours with equivalent responses at 10.50, and 100 ng/ml, whereas the patellar tendon only responded to one condition, 10 ng/ml at 96 hours. Conversely, the patellar tendon had a significant dose-dependent response to platelet-derived growth factor-AB at 72 and 96 hours, whereas the anterior cruciate ligament showed no proliferative response to platelet-derived growth factor-AB. The minimal response of anterior cruciate ligament to platelet-derived growth factor-AB could explain, at least in part, the poor repair capacity of this tissue. The response of the anterior cruciate ligament to transforming growth factor β suggests that exogenous transforming growth factor β may promote initial healing. Although growth factors have the potential to modulate soft-tissue repair, tissue responses in tendons and ligaments may vary at different anatomic sites.     

A unique complication following arthroscopic anterior cruciate ligament reconstruction

The use of the middle third of a patellar tendon with bone blocks is a common and well-accepted technique for arthroscopic reconstruction of the anterior cruciate ligament. We report here a disconcerting fracture/avulsion pattern of the patella/patellar tendon mechanism that occurred in the early postoperative period.     

Radiographic visualization of patellar tendon grafts for the reconstruction of the anterior cruciate ligament

The new biodegradable interference screws offer very many advantages for anterior cruciate ligament replacement with patellar tendon. However, their radiolucency makes it impossible to identify the anchorage sites. We describe an imaging technique of the plasty and its anchorage sites by means of a radiopaque contrast that is commonly used in radiology (Iopamidol; Bracco, Milan, Italy). It is an easy technique that does not extend the time of surgery, it is harmless, and allows us to identify malpositioning or impingement of the plasty.     

关节镜下膝前交叉韧带重建术疗效分析

目的：探讨自体中1／3骨－髌腱－骨（B－PT－B）重建前交叉韧带（ACL）的临床效果。方法：1996年9月－2000年10月对13例膝ACL损伤，其中男9例，女4例，年龄23－45岁。均采用关节镜下自体中1／3B－PT－B重建ACL，挤压螺钉固定，治疗CAL损伤后关节不稳定，术前抽屉试验13例均为阳性，轴移试验4例阳性，Lachman试验7例阳性，术后获随访5－25个月，平均15个月。结果：术后屉试验，轴移试验和Lachman试验均转阴性。按照Bosaotta的术后临床指标评价方法，优9例，良3例，可1例，所有患者均感膝关节稳定性明显改善。结论：关节镜下自体中1／3B－PT－B重建ACL损伤疗效显著。     

前交叉韧带重建术后关节镜下股部肌力测量

目的　观察自体中1/3 骨-髌韧带-骨为供区,重建前交叉韧带后对股部肌力的影响。方法　自体中1/3 骨-髌韧带-骨移植重建前交叉韧带术后1年,关节镜下再视观察到无膝内紊乱的患者23 例;男9 例,女14 例。平均年龄为20.8岁。所有患者在关节镜再视术前使用MyretRZ-450型CybexⅡ等速肌肉功能测试器,对患侧和健侧进行股四头肌和腘绳肌的等长(60°和90°)和等速(60°/s和180°/s)肌力测定。结果　自体中1/3骨-髌韧带-骨做为供区,重建前交叉韧带之侧别的股四头肌肌力比健侧的股四头肌肌力明显降低(P< 0.01)。而获取自体中1/3 骨-髌韧带-骨移植后,对腘绳肌肌力则无影响(P> 0.05)。结论　获取自体中1/3 骨-髌韧带-骨移植重建前交叉韧带后,可严重降低股四头肌肌力     

Distribution of cellular repopulation and collagen synthesis in a canine anterior cruciate ligament autograft

Whether the central core of an anterior cruciate ligament autograft reconstruction is nutritionally compromised at a time when revascularization is known to be complete has not been determined by methods that detect matrix synthesis. In a canine model of anterior cruciate ligament reconstruction with patellar tendon autograft, the adequacy of the supply of metabolites for cellular matrix synthesis was determined by autoradiographic analysis. Total collagen synthesis and cellularity were also quantified. Total collagen synthesis was found to be significantly elevated (p = 0.014 by analysis of variance) in the ligament reconstructions as compared with normal anterior cruciate ligaments or patellar tendons, but cellularity was not (p = 0.13 by analysis of variance). Autoradiography demonstrated even distribution of [³H]proline incorporation throughout the graft and normal tissue. When revascularization was complete, there was an adequate supply of metabolites for cellular synthesis of protein macromolecules within all regions of the ligament reconstruction. At 3 months after reconstruction, the grafts were found to be actively remodeling their collagen matrix. Since the long-term function of an anterior cruciate ligament autograft is dependent on viable fibroblasts to maintain the collagen matrix, the canine anterior cruciate ligament reconstruction contains living cells that are able to remodel the matrix under appropriate conditions.     

Bollen's jig and anterior cruciate ligament reconstruction

We report the design of a surgical instrument that facilitates the harvest of the autologous patellar tendon in anterior cruciate ligament (ACL) reconstruction. The advantage of this jig is that it is a simple, self-centring device resulting in a reproducible and consistent autograft. Its use also minimises the potential risks of donor site morbidity such as patellar fracture and tendon rupture. We briefly describe our technique and discuss its advantages.     

History of surgery of the anterior cruciate ligament

Early comments on the anterior cruciate ligament were found in ancient literature, and the first scientific reports were published in the nineteenth century. The first surgical treatment of a ruptured anterior cruciate ligament was carried out in 1895 by Robson performing a primary suture of the torn ligament. In 1903 F. Lange suggested a complete replacement of the injured ligament using silk ligaments and in 1914 Grekow was probably the first who recommended autogenous transplants by using a fascia lata strip. In 1917 Hey-Groves presented his surgical technique that was the fundament for reconstruction surgery in the following years. Today, the autogenous transplant is accepted to be the golden standard for replacement of the injured anterior cruciate ligament. The bone-tendon-bone transplant of the patellar ligament and the semitendinosus or gracilis tendon are recommended by most surgeons. In the history of anterior cruciate ligament surgery, the surgical technique of the operative procedures has also changed. The evolution started with open arthrotomy followed by mini-arthrotomy and led to arthroscopically assisted replacement of the anterior cruciate ligament.     

Patellar tendon autograft harvesting using a mini vertical incision.

Patellar tendon autograft is a commonly used graft for anterior cruciate ligament reconstruction. Harvesting the patellar tendon graft typically entails using a longer incision than other graft options. We describe a technique for harvesting bone-patellar tendon-bone autograft using a smaller more cosmetic incision.     

Effect of Donor Age on Patellar Tendon Allograft ACL Reconstruction

Anterior cruciate ligament reconstruction with patellar tendon allograft tissue is a common orthopedic procedure. It is unknown what effect, if any, the donor age has on clinical outcomes. Biomechanical studies have shown the strength of cadaveric patellar tendon to be independent of age, but no clinical studies have evaluated patient outcomes related to this variable. The purpose of this study was to evaluate the effect of allograft donor age on clinical outcomes of patients undergoing allograft anterior cruciate ligament reconstruction with patellar tendon allograft.Case logs were reviewed to identify primary anterior cruciate ligament reconstruction with allograft patellar tendon by a single surgeon using a standard endoscopic transtibial technique with interference screw fixation. Revision and multiligamentous surgeries were excluded. Seventy-seven patients who met these criteria were identified. Allografts were fresh-frozen, aseptically harvested patellar tendons from a single tissue bank. The donor age was obtained. Clinical outcomes were obtained by contacting patients by telephone and retrospective chart review. Pre- and postoperative Lysholm and Tegner knee scores were used for comparison.Data from 75 patients with an average follow-up of 24 months were obtained. Average donor age was 44 years (range, 14-65 years), and average patient age was 37 years (range, 18-60 years). Statistical analysis of pre- and postoperative Lysholm scores demonstrated statistically significant improvement (P?.001). Using donor age as a continuous variable, no effect was found on postoperative improvement in Lysholm score or Tegner score (P=.6).