指深屈肌腱及指伸肌腱止点的解剖研究

目的　通过解剖研究指深屈肌腱及指伸肌腱在远节指骨基底掌侧和背侧止点平面的差别，为西摩骨折发生机制提供解剖学依据。 方法　手部残肢10具，其中左手3例，右手7例，均为男性患者，年龄24~58岁。2~5指分别有10指，全部手指无外伤手术史、无畸形。自远节指间关节水平掌侧及背侧分别切开，于末节指骨水平分离各指的指深屈肌腱及指伸肌腱，记录其与末节指骨掌侧及背侧关节面的距离，比较指深屈肌腱及指伸肌腱在末节指骨掌、背侧的止点水平。 结果　指深屈肌腱止点近端至关节面距离：示指（2.19±0.27）mm，中指（2.50±0.14）mm，环指（2.23±0.16）mm，小指（1.83±0.19）mm；指伸肌腱止点近端至关节面距离：示指（0.12±0.02）mm，中指（0.18±0.02）mm，环指（0.12±0.05）mm，小指（0.06±0.01）mm；各指差异有统计学意义（P＜0.05）。指深屈肌腱止点中点至关节面距离：示指（3.73±0.45）mm，中指（4.33±0.45）mm，环指（3.53±0.46）mm，小指（3.16±0.41）mm；指伸肌腱止点中点至关节面距离：示指（1.77±0.06）mm，中指（1.76±0.20）mm，环指（1.77±0.06）mm，小指（1.47±0.10）mm；各指差异有统计学意义（P＜0.05）。 结论　指伸肌腱在末节指骨基底的止点较指深屈肌腱的止点距关节面更近，为西摩骨折的发生机制提供了解剖依据。     

指深屈肌腱及指伸肌腱止点的解剖研究

目的　通过解剖研究指深屈肌腱及指伸肌腱在远节指骨基底掌侧和背侧止点平面的差别,为西摩骨折发生机制提供解剖学依据。 方法　手部残肢10具,其中左手3例,右手7例,均为男性患者,年龄24~58岁。2~5指分别有10指,全部手指无外伤手术史、无畸形。自远节指间关节水平掌侧及背侧分别切开,于末节指骨水平分离各指的指深屈肌腱及指伸肌腱,记录其与末节指骨掌侧及背侧关节面的距离,比较指深屈肌腱及指伸肌腱在末节指骨掌、背侧的止点水平。 结果　指深屈肌腱止点近端至关节面距离：示指（2.19±0.27）mm,中指（2.50±0.14）mm,环指（2.23±0.16）mm,小指（1.83±0.19）mm;指伸肌腱止点近端至关节面距离：示指（0.12±0.02）mm,中指（0.18±0.02）mm,环指（0.12±0.05）mm,小指（0.06±0.01）mm;各指差异有统计学意义（P＜0.05）。指深屈肌腱止点中点至关节面距离：示指（3.73±0.45）mm,中指（4.33±0.45）mm,环指（3.53±0.46）mm,小指（3.16±0.41）mm;指伸肌腱止点中点至关节面距离：示指（1.77±0.06）mm,中指（1.76±0.20）mm,环指（1.77±0.06）mm,小指（1.47±0.10）mm;各指差异有统计学意义（P＜0.05）。 结论　指伸肌腱在末节指骨基底的止点较指深屈肌腱的止点距关节面更近,为西摩骨折的发生机制提供了解剖依据。     

The fourth lumbrical muscle in the hand: a variation of insertion on the fifth finger

Usually the four lumbrical muscles arise from the tendons of flexor digitorum profundus and insert into the extensor expansions on the radial side of the corresponding fingers. This special case showed a very rare variation of a unipennate fourth lumbrical muscle of the right hand; the muscle fibre bundles originated on the radial side of the flexor digitorum profundus and coursed horizontal on its radial side, deep to the palmar aponeurosis and in front of the deep transverse metacarpal ligament over the fifth metacarpophalangeal joint. At the level of this joint, its tendon divided into one radial and one ulnar slips. Both heads surrounded the tendons of the flexor digitorum superficialis and profundus muscles, and found their insertion into the flexor digitorum superficialis tendon, as well as their bony attachment into the proximal and even more into the middle phalanx.     

Anomalous flexor of the little finger

We report an anomalous palmar muscle belly of the flexor digitorum superficialis muscle (FDS) in the right hand of an 80-year-old female cadaver. The muscle originated from the center of the volar surface of the flexor retinaculum and inserted onto the palmar aspect of the base of the middle phalanx of the little finger. Its tendon of insertion divided into two bands, a pattern typical of the FDS tendon, between which the tendon of flexor digitorum profundus muscle to the little finger passed. The tendon of the usual antebrachial FDS to the little finger was absent. The anomalous muscle belly was innervated by a branch from the median nerve.     

基于Anybody软件平台冷水刺激前后食指动力学的特性

背景：Anybody人体建模仿真系统是计算机辅助人类工效学和生物力学分析软件,并且是目前惟一可以分析完整骨骼肌肉系统的软件,利用它可以计算模型中骨骼、肌肉、关节的受力变形。 目的：实验旨在通过计算模型观察手指在冷水刺激环境下食指的灵活性。 方法：参照以往人食指运动实验结果,获得人食指弯曲的运动学参数,利用Anybody软件平台构建正常人手部握拳运动学模型,并进一步构建了包含两根外屈肌(指浅屈肌和指深屈肌)的骨骼肌肉模型,通过逆向动力学分析,考察受冷水刺激前后手部握拳运动时肌肉力和收缩功率等的变化。 结果与结论：冷水刺激后,食指各关节在屈伸过程中的平均角速度较冷水刺激前变小,指浅屈肌的肌肉力变化幅值也较冷水刺激前增大;指深屈肌的收缩功率下降明显,而指浅屈肌收缩功率变化不大。结果证实,冷水刺激会使正常人手握拳动作变慢,且正常人手的指浅屈肌对冷水刺激更敏感,进一步说明指浅屈肌在握拳动作中的重要性。     

An anomalous accessory flexor digiti minimi profundus muscle: A case study

A well-developed anomalous muscle within the forearm flexor compartment was discovered during a routine cadaveric dissection. The identified muscle originated from the intercompartmental septum on the medial side of the forearm just proximal to the wrist joint and inserted on the proximal phalanx of the fifth digit. When stressed, the tendon of the muscle produced flexion of the metacarpophalangeal joint of the fifth digit. Contiguous muscles, including the flexor digitorum profundus, displayed normal morphology. The muscle appeared to be an accessory belly of flexor digitorum profundus. The combination of an accessory flexor digitorum profundus muscle belly acting on the metacarpophalangeal joint of the little finger has not been previously reported. Based on its origin, insertion, and action we have named this variant accessory flexor digiti minimi profundus. This muscular variant could have clinical relevance, possibly affecting ulnar nerve function and circulation in the hand. Clin. Anat. 11:55–59, 1998. © 1998 Wiley-Liss, Inc.     

Announcement

The lumbrical muscle is clearly one of several possible extensors of the interphalangeal joints. With an origin on the flexor digitorum profundus tendon it is credited with unloading the elastic tension across the interphalangeal joints and thereby facilitating their extension. Its role at the metacarpophalangeal joint is not a matter of universal aggreement. Attempts to simulate its action with weights over pulleys have not clarified this role, since true simulation would require the development of a means of applying force along the course of the lumbrical without pre-determining which end would move. Such a system is herein described; it uses a Bowden cable, which is commonly used to activate the brakes of a bicycle. After constructing length-tension curves of the profundus muscle in four fresh cadavers prior to the onset of rigor mortis, the interaction of realistic lumbrical loads with profundus elastic tension was studied. By contraction a lumbrical muscle adds a small but significant flexor force at the metacarpophalangeal joint, and thereby it is also capable of contributing to radial deviation and possibly rotation. As it runs from a flexor tendon to an extensor tendon and is endowed with a great many muscle spindles the lumbrical could play a part in the control of finger movement by monitoring the rate of hand closing during grasp.     

Lumbrical muscle function as revealed by a new and physiological approach

The lumbrical muscle is clearly one of several possible extensors of the interphalangeal joints. With an origin on the flexor digitorum profundus tendon it is credited with unloading the elastic tension across the interphalangeal joints and thereby facilitating their extension. Its role at the metacarpophalangeal joint is not a matter of universal agreement. Attempts to simulate its action with weights over pulleys have not clarified this role, since true simulation would require the development of a means of applying force along the course of the lumbrical without pre-determining which end would move. Such a system is herein described; it uses a Bowden cable, which is commonly used to activate the brakes of a bicycle. After constructing length-tension curves of the profundus muscle in four fresh cadavers prior to the onset of rigor mortis, the interaction of realistic lumbrical loads with profundus elastic tension was studied. By contraction a lumbrical muscle adds a small but significant flexor force at the metacarpophalangeal joint, and thereby it is also capable of contributing to radial deviation and possibly rotation. As it runs from a flexor tendon to an extensor tendon and is endowed with a great many muscle spindles, the lumbrical could play a part in the control of finger movement by monitoring the rate of hand closing during grasp.     

Enslaving effects in multi-finger force production

When a person produces isometric force with one, two, or three fingers, the other fingers of the hand also produce a certain force. Enslaving is the involuntary force production by fingers not explicitly involved in a force-production task. This study explored the enslaving effects (EE) in multi-finger tasks in which the contributions of the flexor digitorum profundus (FDP), flexor digitorum superficialis (FDS), and intrinsic muscles (INT) were manipulated. A new experimental technique was developed that allows the redistribution of the muscle activity between the FDP, FDS, and INT muscles. In the experiment, ten subjects were instructed to perform maximal voluntary contractions with all possible one-, two-, three-, and four-finger combinations. The point of force application was changed in parallel for the index, middle, ring, and little fingers from the middle of the distal phalanx, to the distal interphalangeal joint, and then to the proximal interphalangeal joint. It was found that: (1) the EE of similar amplitude were present in various experimental conditions that involved different muscle groups for force production; (2) the EE were large on average--the slave fingers could produce forces reaching 67.5% of the maximal forces produced by themselves in a single-finger task; (3) the EE were larger for neighboring fingers; and (4) the EE were non-additive--in most cases, the EE from two or three fingers were smaller than the EE from at least one finger. EE among different muscles suggest a widespread neural interaction among the structures controlling flexor muscles in the hand as the main mechanism of finger enslaving.     

A Case of the Bilateral Duplicate Palmaris Longus Muscles Coupled with the Palmaris Profundus Muscle

The palmaris longus muscle is one of the most variable muscles in human anatomy. During a routine anatomical dissection for medical students at Tottori University, we found duplicate palmaris longus muscles in the bilateral forearms together with the palmaris profundus muscle in the right forearm. The bilateral aberrant palmaris longus muscles were observed at the ulnar side of the palmaris longus muscle and their distal tendons were attached to the flexor retinaculum. The palmaris profundus muscle found in the right forearm was located at the radial side of the flexor digitorum superficialis muscle. The proximal tendon was originated from the anterior surface in the middle of the radius, while the distal tendon coursed radial to the median nerve through the carpal tunnel, finally inserting into the distal part of the flexor retinaculum. Both the palmaris longus and aberrant palmaris longus muscles were innervated by the median nerve. The palmaris profundus muscle was presumably supplied by the median nerve.     

Effect of toe and heel elevation on calculated tendon strains in the horse and the influence of the proximal interphalangeal joint

The sagittal alteration of hoof balance is a common intervention in horses, with corrective shoeing being one of the most frequently applied methods of managing tendonitis. However, the effect of toe or heel elevation on tendon strains is poorly understood. This study aimed to examine the effect of toe and heel wedges on the superficial digital flexor tendon, deep digital flexor tendon, and the third interosseous muscle or suspensory ligament strains using in vivo data and an accurate subject-specific model. Kinematic data were recorded using invasive markers at the walk and trot. Computerized tomography was then used to create a subject-specific model of an equine distal forelimb and strains were calculated for the superficial digital flexor tendon, the deep digital flexor tendon accessory ligament and the suspensory ligament for seven trials each of normal shoes, and toe and heel elevation. As the proximal interphalangeal joint is often ignored in strain calculations, its influence on the strain calculations was also tested. The deep ligament showed the same results for walk and trot with the heel wedge decreasing peak strain and the toe wedge increasing it. The opposite results were seen in the suspensory ligament and the superficial digital flexor tendon with the heel wedge increasing peak strain and the toe wedge decreasing it. The proximal interphalangeal joint was shown to be influential on the strains calculated with normal shoes and the calculated effect of the wedges. Our results imply that corrective shoeing appears to decrease strain in the tendon being targeted; the possibility of increases in strain in other structures should also be considered.     

Tendineal arteries of the flexor tendons in the human hand

Two hundred upper extremities of fresh human cadavers were used to study the anatomy of the tendinous apparatus of the flexor digitorum profundus (FDP) and flexor digitorum superficialis (FDS) muscles. This study describes the different types of mesotendons revealed by layered dissection, and the complex arterial network of the structures and their various sources of blood supply as revealed by the injection of colored latex or India ink solution in gelatin.     

远节指骨的解剖学观察及其临床意义

目的：为人工肌腱修复指深屈肌腱或拇长屈肌腱固定方法和固定止点提供解剖学依据。方法：采用常规固定的16具成人手指标本(男、女各80个手指)。观察各指远节指骨长度，底和粗隆的宽度及厚度。结果：男性拇、示和中指远节指骨底的宽度为15．3、10．2、10．5mm，厚度分别为8．8、6．5、7．1mm。女性宽度分别为12．9、9．1、9．6mm，厚度分别为7．8、5．9、6．6mm。男性拇、示和中指远节指骨粗隆宽度为9．4、6．6、7．4mm，厚度分别为3．6、3．2、3．6mm。女性宽度分别为8．0、5．8、6．2mm，厚度分别为3．0、2．7、3．1mm。结论：用人工肌腱修复指深屈肌腱或拇长屈肌腱时，在远节指骨的底部可行螺丝固定，在粗隆可行钻孔固定。     

指浅屈肌腱束经骨隧道重建中央腱止点的解剖学研究

目的　模拟指浅屈肌腱束经骨隧道重建中央腱止点的手术方法,验证手术可行性和安全性。 方法　采用8例新鲜成人尸体手标本,用示、中、环指共24指,解剖观测指浅屈肌腱及中央腱、伸肌腱的相关解剖结构。选取12指（示、中、环指各4指）新鲜成人手指标本进行模拟手术,均人为设计中央腱止点断裂。将指浅屈肌腱两侧部分腱束从中节掌侧止点处经指骨钻孔后引至背侧,与背侧中央腱断端编织缝合重建中央腱止点,测量不同缝合间距的PIP（近指间关节）被动伸直角度和被动屈曲角度。 结果　指浅屈肌腱缝合间距大时,被动伸屈角度大,但中央腱和指浅屈肌腱松弛明显;指浅屈肌腱缝合间距小时,被动伸屈角度小,且中央腱和指浅屈肌腱张力大,均不能保证手指被动伸屈活动。指浅屈肌腱的缝合间距在1.5 cm时,PIP的被动屈曲角度约75°,缝合间距在1.0 cm时,PIP的被动屈曲角度约30°,缝合间距在1.0~1.5 cm时,即切取到Camper腱交叉时,PIP被动伸直和屈曲角度最接近手指功能位时的角度。 结论　切取转移的指浅屈肌腱至Camper腱交叉时可以完成中央腱止点重建,供腱损伤小,重建止点是相对安全和可行的。     

指浅屈肌腱束经骨隧道重建中央腱止点的解剖学研究

目的　模拟指浅屈肌腱束经骨隧道重建中央腱止点的手术方法，验证手术可行性和安全性。 方法　采用8例新鲜成人尸体手标本，用示、中、环指共24指，解剖观测指浅屈肌腱及中央腱、伸肌腱的相关解剖结构。选取12指（示、中、环指各4指）新鲜成人手指标本进行模拟手术，均人为设计中央腱止点断裂。将指浅屈肌腱两侧部分腱束从中节掌侧止点处经指骨钻孔后引至背侧，与背侧中央腱断端编织缝合重建中央腱止点，测量不同缝合间距的PIP（近指间关节）被动伸直角度和被动屈曲角度。 结果　指浅屈肌腱缝合间距大时，被动伸屈角度大，但中央腱和指浅屈肌腱松弛明显；指浅屈肌腱缝合间距小时，被动伸屈角度小，且中央腱和指浅屈肌腱张力大，均不能保证手指被动伸屈活动。指浅屈肌腱的缝合间距在1.5 cm时，PIP的被动屈曲角度约75°，缝合间距在1.0 cm时，PIP的被动屈曲角度约30°，缝合间距在1.0~1.5 cm时，即切取到Camper腱交叉时，PIP被动伸直和屈曲角度最接近手指功能位时的角度。 结论　切取转移的指浅屈肌腱至Camper腱交叉时可以完成中央腱止点重建，供腱损伤小，重建止点是相对安全和可行的。     

Anomalous muscle belly to the index finger.

An unusual variation of flexor digitorum superficialis was observed during the cadaver dissection. The flexor digitorum superficialis (FDS) had a normal origin and insertion, except to the index finger, where a muscle belly replaced the tendon of FDS. The unusual muscle belly originated as a continuation of FDS tendon in the carpal tunnel and inserted normally into the middle phalanx. A branch of the median nerve innervated the anomalous muscle belly. The anomalous muscle belly described here should be considered in the aetiology of carpal tunnel syndrome.     

The hand as a concept: Digital differences and their importance

Digits of the hand vary from each other with respect to bone and joint architecture, muscles, tendons, and degree of functional independence. The hand may be conceived as having a central rigid framework moved at the wrist by flexors, extensors, abductors, and adductors. But on each side of this central structure lies a mobile (hinged) segment necessary for pinch and to increase the strength of grasp. At the distal end of this triplex framework lie multijointed appendages essential for any type of pinch or grasp more sophisticated than that of a lobster claw. The thumb has a highly mobile carpometacarpal joint but lacks a middle phalanx. Therefore, it has no proximal interphalangeal (PIP) joint and consequently no mechanical need for a lumbrical. Since the thumb has excellent coordination without a lumbrical, the lumbrical's function as a sense organ cannot be simply to coordinate finger movement. Mechanically the lumbrical is a deflexor of the PIP joint. Because lumbricals are richly endowed with muscle spindles, their passive stretch by contraction of the flexor digitorum profundus might both inhibit finger extensors and facilitate wrist extensors. Since each digit is unique, accurate mathematical and computer modelling of the hand must take into consideration this uniqueness. © 1995 WiIey-Liss, Inc.