Abstract
目的
探讨关节镜辅助下内侧髌股韧带重建术治疗髌骨脱位股骨侧止点定位方法及效果。
方法
2014 年 1 月—2018 年 9 月,收治 35 例髌骨脱位患者。男 14 例,女 21 例;年龄 16~38 岁,平均 22.6 岁。患者均有膝关节扭伤史;病程 1~7 d,平均 2.8 d。髌骨脱位 2~4 次,平均 2.5 次。术前 Lysholm 评分为(47.60±11.24)分,Kujala 评分为(48.37±9.79)分。髌股适合角为(31.40±6.81)°、髌骨倾斜角为(29.95±5.44)°、外侧髌股角为(−11.46±5.18)°,胫骨结节-股骨滑车间距为(16.66±1.28)mm。于关节镜辅助下取自体半腱肌重建内侧髌股韧带,在髌骨内缘中点与中上 1/3 点应用带线锚钉固定韧带,分别在内收肌大结节、股骨内上髁及其两点间中点以及偏前、偏后位置钻入克氏针,将肌腱固定于克氏针,膝关节屈曲过程中观察韧带等长性、张力、髌骨轨迹及髌股对合关系,选择最佳股骨侧止点重建内侧髌股韧带。术后影像学检查测量髌股适合角、髌骨倾斜角、外侧髌股角,评估髌股对合关系;应用 Lysholm 评分与 Kujala 评分评价膝关节功能。
结果
术后切口均Ⅰ期愈合,无膝关节及切口感染发生。患者均获随访,随访时间 12~18 个月,平均 15.4 个月。术后 12 个月,Lysholm 评分为(94.40±3.99)分、Kujala 评分为(92.28±4.13)分,均较术前明显改善(P<0.05)。随访期内均无髌骨再脱位发生。术后 12 个月髌股适合角为(6.57±4.59)°、髌骨倾斜角为(9.73±2.82)°、外侧髌股角为(7.14±4.63)°,均较术前明显改善(P<0.05)。
结论
关节镜辅助下有限切开重建内侧髌股韧带时,应用股骨侧解剖标志定位,通过观察内侧髌股韧带张力、等长性以及髌股关节对合关系、髌骨轨迹,可以使股骨侧止点定位更准确,临床效果满意。
Keywords: 髌股关节, 髌骨脱位, 内侧髌股韧带, 韧带重建, 股骨侧止点
Abstract
Objective
To investigate the technique of optimizing the location of femoral attachment in medial patellofemoral ligament (MPFL) reconstruction assisted with arthroscopy and evaluate the effectiveness.
Methods
Between January 2014 and September 2018, 35 patients with patellar dislocation were admitted. There were 14 males and 21 females with an average age of 22.6 years (range, 16-38 years). All patients had a history of knee sprain. The disease duration ranged from 1 to 7 days (mean, 2.8 days). Patellar dislocation occurred 2-4 times (mean, 2.5 times). The preoperative Lysholm score and Kujala score were 47.60±11.24 and 48.37±9.79, respectively. The patellar congruence angle was (31.40±6.81)°, the patellar tilt angle was (29.95±5.44)°, the lateral patellofemoral angle was (−11.46±5.18)°, and the tibial tubercle-trochlear groove distance was (16.66±1.28) mm. All patients were treated by MPFL reconstruction with the semitendinosus tendon under arthroscopy. During operation, the suture anchors were inserted into the midpoint and the 1/3 point of superomedial edge of the patella. Then, the femoral tunnels were created in medial femoral condyle through limited excision. For tendon fixation, the Kirschner wires were inserted into adductor tubercle, medial epicondyle of femur, and the midpoint between the two points, as well as the anteriorly and posteriorly. Afterwards, the changes of ligament length and tension, patellar tracking, and the relationship of patella and femoral trochlea were evaluated, thereby determining the optimized femoral attachment for MPFL reconstruction. Finally, the patellar congruence angle, patellar tilt angle, and lateral patellofemoral angle were measured by imaging to assess the relationship of patella and femoral trochlea. Moreover, Lysholm score and Kujala score were used to evaluate the knee joint function.
Results
All incisions healed by first intention without infection. All patients were followed up 12-18 months (mean, 15.4 months). At 12 months, the Lysholm score was 94.40±3.99 and the Kujala score was 92.28±4.13, which were significant higher than those before operation (P<0.05). No patellar dislocation occurred during follow-up. At 12 months, the patellar congruence angle was (6.57±4.59)°, the patellar tilt angle was (9.73±2.82)°, the lateral patellofemoral angle was (7.14±4.63)°, which were superior to those before operation (P<0.05).
Conclusion
During the MPFL reconstruction under arthroscopy, a higher positioning accuracy for the femoral attachment and satisfactory effectiveness can be obtained by evaluating MPFL length and tension, patellofemoral joint kinematics, and patellar tracking.
Keywords: Patellofemoral joint, patellar dislocation, medial patellofemoral ligament, ligament reconstruction, femoral attachment
髌骨脱位是临床常见疾病,往往由扭伤等轻微外伤诱发,可导致内侧髌股韧带断裂、软骨损伤等,进而造成髌股关节不稳、关节生物力学发生改变,诱发髌股关节软骨和软骨下骨损伤,最终发生髌股关节炎,影响膝关节功能。因此,髌骨脱位后恢复髌股关节稳定性及正常应力分布具有重要意义[1]。内侧髌股韧带是维持髌股关节稳定性的重要结构,内侧髌股韧带重建术是常用的治疗复发性髌骨脱位方法,术中内侧髌股韧带股骨侧止点位置的选择对于临床效果具有重要影响,止点位置不良可导致韧带张力欠佳、髌骨运动轨迹异常、膝前疼痛,并且韧带失效及髌骨再脱位风险增高[2]。但目前尚无精准定位股骨侧止点的最佳方法,一般认为内侧髌股韧带重建术中股骨侧解剖止点是内侧髌股韧带的等长点[3]。因此,我们在关节镜辅助下有限切开重建内侧髌股韧带时,显露并参考股骨侧大收肌结节、股骨内上髁等解剖结构,通过观察重建韧带等长性、张力、髌骨运动轨迹及髌股关节对合关系,确定内侧髌股韧带股骨侧止点,临床应用获得较好疗效。报告如下。
1. 临床资料
1.1. 患者选择标准
纳入标准:① 髌骨脱位 2 次及以上;② 髌骨内侧结构松弛,外移距离超过 1/2 髌骨横径;③ MRI 检查显示内侧髌股韧带撕裂、骨软骨损伤、骨骺闭合,无高位髌骨;④ CT 检查显示胫骨结节-股骨滑车间距(tibial tubercle-trochlear groove distance,TT-TG)<20 mm,股骨滑车 Dejour 分型为 A、B 型。
排除标准:① 膝关节既往发生骨折,有手术史;② 心、肺等重要器官存在重大疾病或合并精神障碍不能配合治疗者;③ 股骨滑车 Dejour 分型 C、D 型或髌股关节存在明显畸形。
2014 年 1 月—2018 年 9 月,平煤神马医疗集团总医院骨科共 35 例接受内侧髌股韧带重建术治疗的髌骨脱位患者符合选择标准,纳入研究。
1.2. 一般资料
本组男 14 例,女 21 例;年龄 16~38 岁,平均 22.6 岁。左膝 16 例,右膝 19 例。患者均有膝关节扭伤史;病程 1~7 d,平均 2.8 d。髌骨脱位 2~4 次,平均 2.5 次。主要临床症状为患侧膝关节肿胀、疼痛,屈伸活动障碍。术前 Lysholm 评分为(47.60±11.24)分,Kujala 评分为(48.37±9.79)分。髌股适合角为(31.40±6.81)°、髌骨倾斜角为(29.95±5.44)°、外侧髌股角为(–11.46±5.18)°,TT-TG 为(16.66±1.28)mm。股骨滑车 Dejour 分型为 A 型 30 例、B 型 5 例。
1.3. 手术方法
蛛网膜下腔阻滞麻醉联合持续硬膜外麻醉后,患者取仰卧位,常规消毒、铺巾,患肢驱血后上止血带。采用膝关节镜标准前内、前外侧入路,常规行膝关节镜检查、清理修整损伤软骨。镜下显示髌骨呈半脱位状态,部分伴髌股关节软骨损伤或剥脱缺损,屈伸膝关节时髌股关节匹配差,髌骨运动轨迹不良。
于胫骨结节内侧 1 cm 作一长约 3 cm 切口,显露并完整取出半腱肌。将肌腱两端编织后对折成双股,肌腱束直径为 5~6 mm。于髌骨内侧作长约 3 cm 切口,显露髌骨内侧缘,完整保留关节囊,切除髌骨内缘皮质骨,制作骨槽;分别于髌骨内缘中点及中上 1/3 点拧入 2 枚带线锚钉,将肌腱固定于髌骨内缘,并将肌腱与周围组织加固缝合。
于膝关节内侧大收肌结节与股骨内上髁前缘作一长约 4 cm 切口,逐层切开,显露大收肌结节及股骨内上髁,分别于大收肌结节、股骨内上髁及其两点间中点以及中点前、后 5 mm 位置钻入 1 枚克氏针[4]。将移植肌腱自关节囊外侧面与皮下筋膜间隧道穿出至股骨侧止点,分别缠绕于不同止点克氏针后紧贴骨面牵拉固定,髌骨复位后在膝关节伸直位标记韧带固定于克氏针的位点;在膝关节屈伸活动 0°~110° 范围内观察评估肌腱等长性,如屈伸过程中肌腱标记的位点相对于克氏针定点移动距离小于 2 mm,同时关节镜下见髌股关节对合良好、屈伸活动轨迹良好,确定为内侧髌股韧带股骨侧最佳止点;应用 5~6 mm 空心钻钻孔,将肌腱引入骨道,应用界面螺钉拧入骨道挤压固定韧带。此时,内侧髌股韧带股骨侧止点位于大收肌结节与股骨内上髁间中点,关节镜下观察见髌股关节恢复正常匹配关系,膝关节屈伸活动中髌骨轨迹明显改善,均在正常范围内,髌股关节接触面分布良好。见图 1、2。本组 2 例患者术中发现外侧张力大,先行外侧支持带松解术[5],然后行内侧髌股韧带股骨侧止点定位。
图 1.
Schematic diagram of operation
手术操作示意图
a. 取自体半腱肌肌腱固定于髌骨内缘中点与中上 1/3 点;b. 股骨内上髁部位切口显露大收肌结节(白箭头)及股骨内上髁(黑箭头);c~e. 分别在股骨内上髁、大收肌结节及其两点间中点钻入克氏针;f~h. 将肌腱自关节囊表面穿入后缠绕固定于克氏针,分别屈膝 30°、60°、110° 观察韧带长度变化
a. Autologous semitendinosus tendon was harvested and folded from the middle point, the graft was inserted into the midpoint and the 1/3 point of superomedial edge of the patella; b. Medial epicondyle of femur (black arrow) and adductor tubercle (white arrow) were exposed by the incision at the medial epicondyle; c-e. Kirschner wires were inserted into adductor tubercle, medial epicondyle of femur, and the midpoint between the two points; f-h. The graft was fixed by the Kirschner wires, and the change of ligament length was observed at 30°, 60°, and 110° of flexion

图 2.
Arthroscopy examination of MPFL before and after reconstructions
内侧髌股韧带重建前后关节镜下观察
a、b. 重建前髌骨半脱位;c、d. 重建后膝关节屈曲 0°、30° 位时髌股关节对合良好
a, b. Patellar dislocation before MPFL reconstruction; c, d. The relationship of patella and femoral trochlea recovered at 0° and 30° of flexion after MPFL reconstruction

1.4. 术后处理及疗效评价指标
术后应用卡盘支具固定膝关节 12 周。患者麻醉苏醒后,开始直腿抬高训练及踝泵训练,促进下肢血循环、防止下肢深静脉血栓形成;术后第 2 天开始膝关节屈曲练习,2 周内屈曲活动度不超过 45°,4 周内屈伸活动范围控制在 0°~90° 内,之后逐渐增加。术后 6 周及 3、6、12、18 个月随访,指导患者膝关节屈伸活动、本体感觉及肌力训练。
术后复查膝关节 X 线片及 CT,测量髌股适合角、髌骨倾斜角、外侧髌股角。观察有无膝关节感染、髌骨骨折、膝关节僵硬等并发症以及髌骨再次脱位发生。采用 Lysholm 评分和 Kujala 评分评价膝关节功能。
1.5. 统计学方法
采用 SPSS25.0 统计软件进行分析。数据以均数±标准差表示,手术前后比较采用配对 t 检验;检验水准 α=0.05。
2. 结果
术后切口均 Ⅰ 期愈合,无膝关节及切口感染发生。患者均获随访,随访时间 12~18 个月,平均 15.4 个月。术后 12 个月,Lysholm 评分为(94.40±3.99)分、Kujala 评分为(92.28±4.13)分,均较术前明显改善,差异有统计学意义(t=–22.814,P=0.000;t=–22.774,P=0.000)。随访期内均无髌骨再脱位发生。影像学复查显示患者髌股关节对合良好;术后 12 个月髌股适合角为(6.57±4.59)°、髌骨倾斜角为(9.73±2.82)°、外侧髌股角为(7.14±4.63)°,均较术前明显改善,差异有统计学意义(t=32.212,P=0.000;t=23.321,P=0.000;t=–26.322,P=0.000)。见图 3。
图 3.
A 23-year-old female patient with right patellar dislocation
患者,女,23 岁,右膝关节髌骨脱位
a、b. 术前膝关节正侧位 X 线片;c. 术前 CT;d、e. 术后 12 个月膝关节正侧位 X 线片;f. 术后 12 个月 CT
a, b. Anteroposterior and lateral X-ray films before MPFL reconstruction; c. Preoperative CT; d, e. Anteroposterior and lateral X-ray films at 12 months after operation; f. CT at 12 months after operation

3. 讨论
内侧髌股韧带是影响髌股关节稳定性的关键性结构,能够限制髌骨向外移位[6-8]。髌骨脱位时多存在内侧韧带损伤[9],修复重建内侧髌股韧带能恢复髌股关节的稳定性,是治疗髌骨脱位常用方法之一[10-11]。内侧髌股韧带重建后,大部分患者可获得满意疗效,但仍有部分患者效果不满意,包括发生膝前痛、髌骨骨折、膝关节活动受限等[12],分析与操作技术相关。研究认为内侧髌股韧带重建术中,股骨骨道位置不良与韧带张力欠佳均会严重影响手术效果,术后不能恢复正常的髌股关节轨迹及应力分布,将加重髌股关节软骨损伤程度,继发骨关节炎[13-15]。研究显示在 2 N 力作用下解剖重建内侧髌股韧带能够恢复正常髌股关节应力分布,而股骨侧止点异常及韧带张力过大均会导致髌股关节应力不佳[16]。
对于内侧髌股韧带的股骨侧止点定位方法,学者们做了大量研究,但尚未达成共识[17-19]。目前大部分术者采用 Schottle 方法,即在侧位 X 线片上于股骨干后方皮质作延长线,分别经过股骨后髁关节面、皮质交接点、Blumensaat 线的拐点作垂线,3 条线交汇区域即为股骨侧止点[20],但该定位法存在一定偏差[21]。因此,如何精准定位股骨侧止点从而改善髌股关节应力,对于获得满意疗效具有重要意义。
本组我们通过有限切开显露解剖结构,参考解剖标志确定最佳股骨侧止点,根据髌骨轨迹、韧带等长性、髌股对称性及髌股关节应力进行选择。术中以髌骨内侧中点与中上 1/3 点作为髌骨解剖止点固定肌腱,以大收肌结节或股骨内侧髁作为股骨侧解剖标志。我们发现当股骨侧止点位于股骨大收肌结节,屈膝时韧带长度明显增加;当止点位于股骨内髁,屈膝时韧带较伸直位短缩;当止点位于两点连线中点偏前 5 mm,屈膝时韧带长度增加,位于两点连线中点偏后 5 mm,屈膝时韧带长度短缩;当止点位于两点连线中点,重建韧带等长性良好。临床结果显示选择股骨内上髁与内收肌结节中点区域作为股骨侧止点重建内侧髌股韧带,内侧髌股韧带长度在膝关节屈伸 0°~110° 范围内接近等长[22-23],并可获得满意效果。但需要注意止点并不完全固定在中点,术中应根据韧带等长性及张力进行适当调整。
相比单纯开放手术,关节镜为膝关节手术治疗提供了较大便利,已广泛用于临床。膝关节镜辅助下,术中能直接观察到膝关节各组织结构,能更准确判断患者病情,能够直接动态观察到髌骨运动轨迹,进而调整重建韧带股骨侧止点及韧带张力,避免由于张力过大或不足导致的手术失败。
研究表明,髌骨轨迹及应力分布对髌股关节功能的影响比软骨更大[24],因此恢复髌股关节正常轨迹及应力分布是手术的根本目标。本组采用的股骨侧止点定位方法不仅能评估重建韧带的等长性及张力,同时还能根据髌骨轨迹及髌股关节对合关系等确定最佳止点,从而恢复膝关节髌股关节的最佳运动学结构,改善膝关节功能,降低后遗症及并发症发生可能。但该方法主要应用于单纯内侧髌股韧带重建,对于合并髌股关节明显畸形效果有待临床应用验证。
作者贡献:张勇参与实验设计、实施、数据收集整理及统计分析,文章撰写;程飚参与实验设计、实施,对文章的知识性内容作批评性审阅;杨林参与实验设计及实施、数据收集整理及统计分析。
利益冲突:所有作者在课题研究和文章撰写过程中不存在利益冲突。
机构伦理问题:研究方案经平煤神马医疗集团总医院伦理委员会批准。
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