Tibial tunnel enlargement after anatomic anterior cruciate ligament reconstruction with a bone–patellar tendon–bone graft. Part 2: Factors related to the tibial tunnel enlargement

BackgroundFactors related to tunnel enlargement after anterior cruciate ligament (ACL) reconstruction should be evaluated by multivariate analysis, because the phenomenon has multifactorial characteristics. The purpose of this study was to elucidate the factors related to the tibial tunnel enlargement rate after anatomic ACL reconstruction with a bone–patellar tendon–bone (BTB) graft using multivariate analysis.MethodsEighteen patients with unilateral ACL rupture were included. The anatomic rectangular-tunnel (ART) ACL reconstruction with a BTB autograft was performed. 3D CT models of the tibia, the tibial tunnel, and the bone plug at 3 weeks and 1 year after surgery were reconstructed and superimposed using a surface registration technique. The cross-sectional area (CSA) of the tibial tunnel perpendicular to the tunnel axis was evaluated at the aperture. The CSA was measured at 3 weeks and 1 year after surgery, and the tunnel enlargement rate at the aperture was calculated. Multiple linear regression analysis was performed to detect the significantly related factors to the tibial tunnel enlargement rate at the aperture among potential factors consisting of preoperative demographic factors and predisposing factors with the tibial tunnel.ResultsThe tibial tunnel enlargement rate at the aperture was 21.9 ± 14.1% (mean ± standard deviation). Multiple linear regression analysis detected the tendon length inside the tunnel as a significantly independent factor related to the tibial tunnel enlargement rate at the aperture (standardized β = 0.726, P = 0.008). There was no significant relationship between the tibial tunnel enlargement rate at the aperture and postoperative side-to-side difference (SSD) of the anterior knee laxity or Tegner activity level scale under single linear regression analysis.ConclusionThe greater tendon length inside the tunnel was independently related to the higher tibial tunnel enlargement rate at the aperture 1-year after anatomic ACL reconstruction with a BTB graft under multiple linear regression analysis.     

Quadriceps tendon-patellar bone autograft for anterior cruciate ligament reconstruction: a technical note

The quadriceps tendon autograft can be used for primary and revision anterior cruciate ligament (ACL) reconstruction. Despite several successful clinical reports, graft fixation issues remain, and the ideal technique for fixation continues to be controversial. We present a technique of ACL reconstruction with quadriceps tendon autograft (QTA) using a patellar bone block. The tendon end is fixed in the femoral tunnel and the bone plug in the tibial tunnel using reabsorbable interference screws. The advantages of this technique are related to the increase in stiffness of the graft, the achievement of a more anatomic fixation, and a reduction in synovial fluid leakage.     

Tibial tunnel enlargement following anterior cruciate ligament reconstruction with patellar tendon autograft

Purpose: The purpose of this study was to prospectively evaluate changes in the tibial bone tunnel following endoscopic anterior cruciate ligament (ACL) reconstruction with patellar tendon autograft. We used computed tomography (CT) sequentially to monitor the time course of these changes over a 2-year period and correlated the results to clinical outcome and instrumented laxity measurements. Type of Study: Case series. Methods: Thirty-four patients (11 women, 23 men; mean age, 26.4 ± 4.5 years) who underwent endoscopic patellar tendon ACL reconstruction, were evaluated clinically according to IKDC, Lysholm, and Tegner scores as well as with respect to changes in tibial tunnel morphology over a 2-year period. Subsequent CT scans were performed at 1 and 6 weeks and at 3, 6, 12, and 24 months postoperatively. The tibial bone tunnel was measured in the sagittal and coronal planes at 5 different levels (L1 to L5). Results: The diameters of the tibial tunnel increased an average overall by 30.6% in the sagittal plane and 16.4% in the coronal plane within 2 years. The enlargement was significantly higher (P <.05) in the mid portion of the tunnel (L 2/3: 44.0% and 47.9% in the sagittal and 29.8% and 29.9% in the coronal plane, respectively), which resulted in a uniform cavity-type appearance. The percentage of change in tunnel size was significantly higher (P <.05) within the first 6 weeks following surgery compared with all other time intervals. No correlation between the amount of tunnel enlargement and the clinical results or between tunnel enlargement and KT-1000 measurements could be detected. Conclusions: Endoscopic ACL reconstruction is associated with tibial tunnel enlargement, which is already present within weeks following surgery. However, no negative effects on the clinical results were found over a 24-month period in our study population.Arthroscopy: The Journal of Arthroscopic and Related Surgery, Vol 17, No 2 (February), 2001: pp 138–143     

Extensor Mechanism Disruption After Contralateral Middle Third Patellar Tendon Harvest for Anterior Cruciate Ligament Revision Reconstruction

The contralateral central third patellar tendon autograft is a reliable graft choice for revision, and recently, for primary reconstruction of the anterior cruciate ligament (ACL). We report 2 complications including a lateral third tibial tuberosity fracture and a distal patellar tendon avulsion with contralateral patellar tendon autograft with disruption of the extensor mechanism of the donor knee. A patient sustained a lateral tibial tuberosity fracture of the donor knee and underwent open reduction and internal fixation. At 1-year follow-up, she had no extensor lag and full range of motion. Another patient sustained a distal patellar tendon avulsion of the donor knee and underwent primary repair. Three years postoperatively, she had a full range of motion and no extensor lag. Although contralateral middle third patellar tendon autograft for primary and revision ACL reconstruction is established in the literature, extensor mechanism complications can occur. Technical considerations are important to avoid weakening the remaining patellar tendon insertion. Postoperative nerve blocks or local anesthetics may alter pain feedback for regulation of weight bearing and contribute to overload of the donor knee.     

自体和异体肌腱移植重建前十字韧带后止点转归的组织学研究

目的：比较自体和异体肌腱移植重建前十字韧带后韧带止点的组织学转归。方法：取12只健康成年杂种犬，切除双膝前十字韧带，切取伸趾肌腱，对折成双股后移植重建前十字韧带，韧带的两端分别通过胫骨和股骨骨隧道后用缝线和螺钉固定．将每条犬的左右侧膝关节随机建成自体或异体的腱-骨愈合模型，采用HE染色，观察比较韧带重建后其止点在6周、12周、6个月时的组织学表现。结果：正常犬的前十字韧带止点具有四层移行结构，即致密结缔组织、纤维软骨、钙化纤维软骨和骨组织，在纤维软骨和钙化纤维软骨之间可见清晰连续的“潮线”。术后6周，自体和异体肌腱重建韧带止点均可见韧带与骨隧道之间充满疏松结缔组织。12周时．自体韧带与骨隧道之间胶原纤维排列有序．并已形成明显的“潮线”．但不连续．四层结构不清；异体韧带与骨隧道之间胶原纤维排列无序，无明显的“潮线”形成，6个月时，自体韧带与骨隧道之间形成明显的“潮线”．且连续，四层结构清晰；异体韧带与骨隧道之间也已形成“潮线”，但“潮线”的起伏性、连续性及结构均较自体韧带差，结论：无论是自体肌腱还是异体肌腱移植重建前十字韧带．6个月后均可初步形成韧带-软骨止点：但在相同时间点．自体肌腱止点的组织学形态优于异体肌腱。     

Histological comparison of after reconstruction of fate of ligamentous insertion anterior cruciate ligament： autograft vs allograft

Objective ：To analyze the histological results and the biological remodeling of ligamentous insertion after the reconstruction of anterior cruciate ligament （ ACL ） with autograft or allograft tendon. Methods： Extensor digitorum tendon was harvested from hind limb as graft material and transplanted to reconstruct the resected ACL in 12 mongrel dogs. Each free tendon end was secured by holding sutures and then the sutures were tied to the post screw at the femoral and tibial bony tunnel outlet after transplantation respectively. Autograft was randomly performed on one side of knee while allograft on the other side of knee. After transplantation, the histological analysis was undertaken at the 6th, 12th weeks and the 6th month using hematoxylineosin （HE） stain under light microscope. Results： The insertion structure of normal ACL typically consisted of four layers, i. e. , dense connective tissue, fibrocartilage, mineralized fibrocartilage and bone. There was a distinct regular tidemark line between fibrocartilage and mineralized fibrocartilage. At the 6th week postoperatively, loose connective tissue presented in the interspace between graft and bony tunnel wall in both autograft and allograft groups. At the 12th week postoperatively, the collagenons fibers between autograft and tunnel wall became well organized and the four layers of insertion with discontinuous tidemark line were demonstrated indistinctly in autograft group but not in allograft group. At the 6th month postoperatively, both of a clear and continuous tidemark line and distinct four layers could be seen in autograft group. In allograft group, only a waved discontinuous tidemark line was shown and either the anatomic morphology or the maturity of insertion was inferior to that of autograft group. Conclusions： At the 6th month postoperatively, although the ligament-eartilage insertion is primarily formed after ACL reconstruction with autograft or allograft tendon, the histological morphology and the maturation of insertion of autograft tendon are better than those of allograft group, which suggests that postoperative rehabilitation should be paid more attention and could be safer if little delayed during ACL reconstruction with allograft tendon.     

Histological comparison of fate of ligamentous insertion after reconstruction of anterior cruciate ligament: autograft vs allograft

Objective: To analyze the histological results and the biological remodeling of ligamentous insertion after the reconstruction of anterior cruciate ligament ( ACL) with autograft or allograft tendon. Methods: Extensor digitorum tendon was harvested from hind limb as graft material and transplanted to reconstruct the resected ACL in 12 mongrel dogs. Each free tendon end was secured by holding sutures and then the sutures were tied to the post screw at the femoral and tibial bony tunnel outlet after transplantation respectively. Autograft was randomly performed on one side of knee while allograft on the other side of knee. After transplantation, the histological analysis was undertaken at the 6th, 12th weeks and the 6th month using hematoxylin-eosin (HE) stain under light microscope. Results: The insertion structure of normal ACL typically consisted of four layers, i. e. , dense connective tissue, fibrocartilage, mineralized fibrocartilage and bone. There was a distinct regular tidemark line between fibrocartilage and mineralized fibrocartilage. At the 6th week postoperativcly, loose connective tissue presented in the interspace between graft and bony tunnel wall in both autograft and allograft groups. At the 12th week postoperatively, the collagenous fibers between autograft and tunnel wall became well organized and the four layers of insertion with discontinuous tidemark line were demonstrated indistinctly in autograft group but not in allograft group. At the 6th month postoperatively, both of a clear and continuous tidemark line and distinct four layers could be seen in autograft group. In allograft group, only a waved discontinuous tidemark line was shown and either the anatomic morphology or the maturity of insertion was inferior to that of autograft group. Conclusions: At the 6th month postoperatively, although the ligament-cartilage insertion is primarily formed after ACL reconstruction with autograft or allograft tendon, the histological morphology and the maturation of insertion of autograft tendon are better than those of allograft group, which suggests that postoperative rehabilitation should be paid more attention and could be safer if little delayed during ACL reconstruction with allograft tendon.     

Arthroscopic anterior cruciate ligament reconstruction with quadriceps tendon-patellar bone autograft

BACKGROUND: Surgical reconstruction of the anterior cruciate ligament (ACL) is indicated in the ACL-deficient knee with symptomatic instability and multiple ligaments injuries. Bone patellar tendon-bone and the hamstring tendon generally have been used. In the present study, we describe an alternative graft, the quadriceps tendon-patellar bone autograft, by using arthroscopic ACL reconstruction. METHODS: From March of 1996 through March of 1997, a quadriceps tendon-patellar bone autograft was used in 12 patients with ACL injuries. RESULTS: After 15 to 24 months of follow-up, the clinical outcome for those patients with this graft have been encouraging. Ten patients could return to the same or a higher level of preinjury sports activity. According to the International Knee Documentation Committee rating system, 10 of the 12 patients had normal or nearly normal ratings. Recovery of quadriceps muscle strength to 80% of the normal knee was achieved in 11 patients in 1 year. CONCLUSION: The advantages of the quadriceps tendon graft include the following: the graft is larger and stronger than the patellar tendon; morbidity of harvest technique and donor site is less than that of patellar tendon graft; there is little quadriceps inhibition after quadriceps harvest; there is quicker return to sports activities with aggressive rehabilitation. A quadriceps tendon-patellar autograft is a reasonable alternative to ACL reconstruction in patients who are not suitable for either a bone-patellar tendon-bone autograft or a hamstring tendon autograft.     

ACL reconstruction by patellar tendon

In 50 knees the length of the anterior cruciate ligament (ACL), the patellar tendon, and the distance between the tibial tuberosity and the femoral origin of the ACL were evaluated by means of three-dimensional magnetic resonance imaging (MRI), which permits subsequent reconstruction of any sectional view. The measurements showed that the patellar tendon was always markedly longer than the ACL (mean 14.4 mm), but always shorter than the distance between the tibial tuberosity and the femoral insertion of the ACL (mean 19.2 mm). The mean lengths of the ACL and the patellar tendon were 38.2 mm and 52.6 mm, respectively. The mean distance between the femoral ACL origin and the tibial insertion of the patellar tendon was 71.8 mm. These results demonstrate that a distally based patellar tendon autograft alone (with the patellar bone block but without extension into the periosteum of the patella or the quadriceps tendon) cannot be placed anatomically correctly to the isometric femoral insertion of the ACL. When the patellar tendon is used for ACL reconstruction, it must be implanted as a free autograft. Nevertheless, considerable variations of length must be taken into account.     

前交叉韧带重建术后骨道增宽的临床研究

目的分析前交叉韧带（ACL）重建术后骨道增宽的发生率、增宽程度、骨道形状、相关因素及其与临床效果的关系。方法回顾性研究应用胭绳肌腱重建ACL手术后骨道的变化,通过X线片测量ACL重建术后的骨道直径。对51例患者行ACL重建手术,其中男性30例,女性21例。所有患者均获随访,平均随访时间16个月。主要研究及观察指标：患者性别、年龄、身高等因素,移植物的固定方式,随访时的关节活动度、膝关节稳定性检查（KT2000）及肌力恢复情况,以及股骨和胫骨的骨道直径、骨道位置和角度等。数据分析采用统计学卡方检验及相关性分析。结果前交叉韧带重建术后的骨道增宽率股骨85％-94％,胫骨65％;增宽程度股骨51％-53％,胫骨40％～44％。胫骨骨道增宽的形态以O型（冠位片）及V型（矢位片）最常见。骨道增宽与年龄、身高及体重指数相关。股骨骨道位置偏前会引起股骨骨道的增宽,股骨骨道角或胫骨骨道角越小,则股骨骨道越容易增宽。结论以腘绳肌腱为移植物重建前交叉韧带手术,术后骨道增宽的发生率与程度,股骨骨道较胫骨骨道明显。骨道增宽与患者年龄、身高以及骨道定位相关,其中股骨和胫骨骨道的位置及角度是引起术后骨道增宽的主要因素之一。骨道增宽与KT2000结果和术后肌力恢复情况相关。     

Tripled semitendinosus anterior cruciate ligament reconstruction with Endobutton fixation: A 2-3-year follow-up study of 35 patients

We evaluated the clinical outcome of tripled semitendinosus tendon ACL reconstruction with femoral Endobutton (Acufex, Smith&Nephew, Andover, MA) and tibial Suture Washer (Acufex, Smith&Nephew, Andover, MA) (n 29) or post screw fixation (n 6) in 35 patients on an average of 28 (20-37) months after surgery. On the basis of IKDC criteria, 22 patients showed a normal or nearly normal knee function and 25 patients had a KT 1000 maximal manual side-to-side difference of ≤5 mm at follow-up. Subjectively, 28 patients graded their knee function as normal or nearly normal. The average Lysholm score was 88 points, average OAK score 90 points and average modified HSS score 93 points. 19 patients reached their preinjury level of activity at follow-up. The postoperative Lachman test was ≤1+ in 24 patients and 24 patients also showed an absent pivot shift. Significant bone tunnel enlargement occurred in 26 patients on the femoral side and in 23 patients on the tibial side. We found no correlation between bone tunnel enlargement and clinical outcome. The clinical outcome of tripled semitendinosus tendon ACL reconstruction with Endobutton fixation on the femoral side was not entirely satisfactory. The procedure was associated with a high incidence of bone tunnel enlargement in this series.     

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.     

Tripled semitendinosus anterior cruciate ligament reconstruction with Endobutton fixation: a 2-3-year follow-up study of 35 patients

We evaluated the clinical outcome of tripled semitendinosus tendon ACL reconstruction with femoral Endobutton (Acufex, Smith&Nephew, Andover, MA) and tibial Suture Washer (Acufex, Smith&Nephew, Andover, MA) (n 29) or post screw fixation (n 6) in 35 patients on an average of 28 (20-37) months after surgery. On the basis of IKDC criteria, 22 patients showed a normal or nearly normal knee function and 25 patients had a KT 1000 maximal manual side-to-side difference of < or =5 mm at follow-up. Subjectively, 28 patients graded their knee function as normal or nearly normal. The average Lysholm score was 88 points, average OAK score 90 points and average modified HSS score 93 points. 19 patients reached their preinjury level of activity at follow-up. The postoperative Lachman test was < or =1+ in 24 patients and 24 patients also showed an absent pivot shift. Significant bone tunnel enlargement occurred in 26 patients on the femoral side and in 23 patients on the tibial side. We found no correlation between bone tunnel enlargement and clinical outcome. The clinical outcome of tripled semitendinosus tendon ACL reconstruction with Endobutton fixation on the femoral side was not entirely satisfactory. The procedure was associated with a high incidence of bone tunnel enlargement in this series.     

Evaluation of bone incorporation of patellar tendon autografts and allografts for ACL reconstruction using CT

Anterior cruciate ligament (ACL) reconstruction is a relatively common orthopedic procedure, with patellar tendon frequently a graft source. However, controversy exists regarding the decision to use autograft or allograft patellar tendon tissue. This experimental study used computed tomography (CT) to compare the percentage of bone graft incorporation following ACL reconstruction using autografts and allografts. Fifty consecutive patients undergoing ACL reconstruction were included in the study. The tibial bone plug was imaged with CT 1 week, 2 months, and 5 months postoperatively. Four images from each completed scan were analyzed for percentage of incorporation of the bone graft. The results of autograft and allograft incorporation for each of the time intervals were compared. No statistically significant difference was found in the amount of bone incorporation at the tibial bone plug 1 week, 2 months, and 5 months. Clinical concerns regarding slower or less complete healing of allograft bone tissue compared to autograft are not supported with regard to the grafts studied.     

前交叉韧带重建失败的原因分析

目的 探讨前交叉韧带（ACL）重建失败后行翻修手术的主要原因以指导临床。方法 回顾性分析2001年11月至2006年7月收治的因ACL重建失败需要行翻修术的13例患者的临床资料,其中男性9例,女性4例,年龄16～46岁,平均29岁。结合临床病例研究分析ACL重建失败的原因。结果 本组13例患者中,初次手术选用自体骨-髌腱-骨移植物（B-PT-B）7例,自体半腱股薄肌腱（STG）4例,同种异体STG2例。翻修原因上、下两端骨道均偏前4例,单独上骨道偏前4例;同种异体STG重建出现明显排异反应取出移植物1例,骨道明显扩大而失败1例;自体B-PT-B重建固定上骨道内骨块的挤压螺钉位置异常2例;术后感染1例。翻修术中重建的ACL完全断裂和吸收7例,韧带有部分连接但已明显松弛失张力4例,内固定物位置异常2例。行膝关节粘连松解手术1例;因骨道骨质缺损严重而行一期植骨术,准备二期翻修2例;其余10例均行一期翻修手术,其中用同侧STG4例、对侧STG4例、同侧B—PT-B1例、髂胫束1例。结论 前交叉韧带重建手术失败的原因较多,但主要与手术骨道位置异常、固定失效、同种异体腱的排异反应与骨道扩大以及感染和术后粘连等有关。     

Patellar tendon rupture 3 years after anterior cruciate ligament reconstruction with a central one third bone–patellar tendon–bone graft

Use of the central one third bone–patellar tendon–bone autograft is an accepted technique for anterior cruciate ligament (ACL) reconstruction. Patellar tendon rupture following ACL reconstruction is an acknowledged, although rarely reported, complication of this procedure. Of the limited patellar tendon rupture cases reported in the literature, most are described early in the postoperative period. We present a case of late patellar tendon rupture more than 3 years after uneventful ACL reconstruction in a 32-year-old man.Arthroscopy: The Journal of Arthroscopic and Related Surgery, Vol 17, No 6 (July-August), 2001: pp 648–652     

膝关节镜下采用挤压螺钉固定骨-髌腱-骨自体移植重建前交叉韧带

目的　探讨采用关节镜下微创手术的方法重建膝关节前交叉韧带。　方法　在膝关节镜下采用挤压螺钉固定骨 髌腱 (中 1/ 3) 骨复合体自体移植重建前交叉韧带 ,术后 1年以上者 2 0例 ,平均随访时间 1年 5个月。　结果　按关节功能评定标准 ,本组 2 0例中 ,优 13例 ,良 5例 ,可 2例 ,优良率 90 % ;9例术后关节镜观察重建前交叉韧带的形态结构 ,7例塑形改建良好。　结论　关节镜下重建前交叉韧带手术创伤小 ,骨道定位准确、固定牢固 ,可做到等长重建 ,有利于早期康复 ;由于利用了自体骨 髌腱 骨组织 ,重建的韧带经塑形改建后可获得牢固的生物学固定     

Tripled semitendinosus anterior cruciate ligament reconstruction with Endobutton fixation: A 2-3-year follow-up study of 35 patients

We evaluated the clinical outcome of tripled semitendinosus tendon ACL reconstruction with femoral Endobutton (Acufex, Smith&Nephew, Andover, MA) and tibial Suture Washer (Acufex, Smith&Nephew, Andover, MA) (n 29) or post screw fixation (n 6) in 35 patients on an average of 28 (20-37) months after surgery. On the basis of IKDC criteria, 22 patients showed a normal or nearly normal knee function and 25 patients had a KT 1000 maximal manual side-to-side difference of &#104 5 mm at follow-up. Subjectively, 28 patients graded their knee function as normal or nearly normal. The average Lysholm score was 88 points, average OAK score 90 points and average modified HSS score 93 points. 19 patients reached their preinjury level of activity at follow-up. The postoperative Lachman test was &#104 1+ in 24 patients and 24 patients also showed an absent pivot shift. Significant bone tunnel enlargement occurred in 26 patients on the femoral side and in 23 patients on the tibial side. We found no correlation between bone tunnel enlargement and clinical outcome. The clinical outcome of tripled semitendinosus tendon ACL reconstruction with Endobutton fixation on the femoral side was not entirely satisfactory. The procedure was associated with a high incidence of bone tunnel enlargement in this series.     

带骨瓣的髌腱中1/3重建前交叉韧带

目的　评价带骨瓣的髌腱中 1/ 3重建前交叉韧带的效果。方法　 1994年 4月～ 1996年 8月 ,共利用带骨瓣的自体髌腱中 1/ 3重建前交叉韧带 8例。结果　 8例均获得 5个月～ 3年随访 ,平均 2 6个月。优 4例 ,良 3例 ,可 1例。术前 5例有明显膝关节不稳定感 ,术后均消失 ;术前 8例均存在 L anchman试验或 /和前抽屉试验阳性 ,术后有 1例呈前抽屉试验阳性 ;所有患者均能基本满足日常生活要求 ,1例仍残存膝关节疼痛。 3例术后存在不同程度的膝关节僵直 ,经过 CPM康复训练后膝关节屈伸活动度可达 0°～ 90°以上。结论　带骨瓣的髌腱中 1/ 3重建前交叉韧带是恢复膝关节功能的理想方法。     

Tibial tunnel enlargement after anatomic anterior cruciate ligament reconstruction with a bone–patellar tendon–bone graft. Part 1: Morphological change in the tibial tunnel

BackgroundThree-dimensional (3D) computed tomography (CT) is reliable and accurate imaging modality for evaluating tunnel enlargement after anterior cruciate ligament (ACL) reconstruction. The purpose of this study was to evaluate the tibial tunnel enlargement including the morphological change after anatomic ACL reconstruction with a bone–patellar tendon–bone (BTB) graft using 3D CT models.MethodsEighteen patients with unilateral ACL rupture were included. The anatomic rectangular-tunnel (ART) ACL reconstruction with a BTB autograft was performed. 3D CT models of the tibia, the tibial tunnel, and the bone plug at 3 weeks and 1 year after surgery were reconstructed and superimposed using a surface registration technique. The cross-sectional area (CSA) of the tibial tunnel perpendicular to the tunnel axis was evaluated at the aperture and 5, 10, and 15-mm distal from the aperture. The CSA was measured at 3 weeks and 1 year after surgery and compared between the two time points. The locations of the center and the anterior, posterior, medial, and lateral edges of the tunnel footprint were also evaluated based on the coordinate system for the tibial plateau and compared between the two time points.ResultsAt the aperture, the CSA of the tibial tunnel at 1 year after surgery was significantly larger by 21.9% than that at 3 weeks (P < 0.001). In contrast, the CSA at 1 year was significantly smaller than that at 3 weeks at 10 and 15-mm distal from the aperture (P = 0.041 and < 0.001, respectively). The center of the tunnel footprint significantly shifted postero-laterally with significant posterior shift of the anterior/posterior edges and lateral shift of the lateral edge (P < 0.001).ConclusionThe tibial tunnel enlarged at the aperture by 22% 1-year after anatomic ACL reconstruction with a BTB graft, and the tunnel morphology changed in a postero-lateral direction at the aperture and into conical shape inside the tunnel.