A loop-tendon suture for tendon transfer or graft surgery

PURPOSE: We present a loop-tendon suture technique that was designed for easy tension adjustment and early postoperative rehabilitation in tendon transfer or graft surgeries. This study tested the biomechanical strength of the loop-tendon suture by using chicken flexor tendons and we report the preliminary clinical results. METHODS: We tested the ultimate strength of the loop-tendon suture against the end-weave suture technique in chicken flexor tendons. Forty flexor digitorum longus tendons of chickens were divided into 2 groups according to the suture technique, loop-tendon suture and end-weave suture groups, and then were subjected to linear loading in a tensile load testing machine. From 2000 to 2002 we performed 27 tendon transfer surgeries clinically, including 4 interpositional tendon grafts in 15 patients, using this technique followed by immediate passive motion exercise after surgery. The mean follow-up time was 20 months. RESULTS: The ultimate tensile load of chicken flexor tendons was 31 +/- 6 N for the loop-tendon suture group and 23 +/- 8 N for the end-weave suture group, and the difference was statistically significant. Clinically, 6 patients with an extensor indicis proprius to an extensor pollicis longus transfer showed more than good results in the Geldmacher scheme. Three patients with an extensor indicis proprius to a central tendon transfer achieved proximal interphalangeal extension of less than 15 degrees of extension lag. One patient with a flexor digitorum profundus reconstruction obtained total active motion of 210 degrees. The 5 patients with triple transfers for radial nerve palsy showed more than neutral extension of the wrist and metacarpal joint. There were no tendon ruptures. CONCLUSIONS: The loop-tendon suture method has greater strength than the conventional end-weave technique, and can be used for secondary tendon reconstruction surgery with favorable clinical outcomes. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic IV.     

Biomechanical influence of the vincula tendinum on digital motion after isolated flexor tendon injury: a cadaveric study

PURPOSE: The vincula are specialized mesotendinous structures attaching to the flexor tendons of the hand. In addition to providing vascular supply to the tendons, the vincula can be mechanically important. The purpose of this study was to quantify the influence of intact vincula on digital flexion after flexor tendon laceration and to assess the ultimate strength and stiffness of the vincula. METHODS: The index, middle, and ring fingers of 12 fresh-frozen cadaveric fingers were dissected free at the level of the metacarpophalangeal joint, preserving at least 10 cm of the flexor and extensor tendons. A 9.8-N load was applied to each flexor tendon, and using digital photography and image analysis software, the degree of flexion at the proximal and distal interphalangeal joints and excursion of tendons proximal to the metacarpophalangeal joint was recorded before and after division of the flexor digitorum profundus and flexor digitorum superficialis tendons at their insertions. Load to failure and stiffness of the vincula were measured via a uniaxial material testing apparatus. Analysis of means was performed with a paired t-test. RESULTS: After division of the flexor digitorum superficialis tendon, proximal interphalangeal joint flexion secondary to the influence of the intact vincula was 93% of that compared with the uninjured digit. Distal interphalangeal joint flexion after flexor digitorum profundus transection was 69% of normal. The increased excursion of transected tendons compared with testing before division was 4 mm for flexor digitorum superficialis and 2 mm for flexor digitorum profundus. Load to failure was 27 N, and stiffness was 6 N/mm. CONCLUSIONS: The vincula breve can facilitate digital flexion after distal tendon transection, allowing tendons to act indirectly across the interphalangeal joints. The intact vincula breve can facilitate an almost normal range of motion across the interphalangeal joints, making the diagnosis of a flexor tendon injury difficult. In the immediate postinjury period, the vincula breve can hold a divided tendon within a few millimeters of its insertion. Testing against resistance is important to avoid missing the diagnosis of a tendon injury.     

Architecture of selected muscles of the arm and forearm: anatomy and implications for tendon transfer.

The architectural features of twenty-one different forearm muscles (n = 154 total muscles) were studied. Muscles included the extensor digitorum communis to the index, middle, ring, and small fingers, the extensor digit quinti, the extensor indicis proprius, the extensor pollicis longus, the flexor digitorum superficialis, the flexor digitorum profundus, the flexor pollicis longus, the pronator quadratus, the palmaris longus, the pronator teres, and the brachioradialis. Muscle length, mass, fiber pennation angle, fiber length, and sarcomere length were determined with the use of laser diffraction techniques. From these values, physiologic cross-sectional area and fiber length/muscle length ratio were calculated. The individual digital extensor muscles were found to be relatively similar in architectural structure. Similarly, the deep and superficial digital flexors were very similar architecturally, with the exception of the small finger flexor digitorum superficialis, which was much smaller and shorter than the rest of the digital flexors. The brachioradialis and the pronator teres had dramatically different architectural properties. While the masses of the two muscles were nearly identical, the muscles had significantly different predicted contractile properties based on their different fiber arrangement. The brachioradialis, with its long fibers arranged at a small pennation angle, had a physiologic cross-sectional area that was only one third that of the pronator teres, with its short fibers that were more highly pennated. Using these architectural data and the statistical method of discriminant analysis, we provide additional information that might be useful in the selection of potential donor muscles to restore thumb flexion, thumb extension, finger extension, and finger flexion.     

Closed tendon injuries of the hand

Cases of subcutaneous tendon ruptures of the hand were compiled over a period of 10 years; the lesions were all traumatic rather than due to degenerative illness. The 914 injuries fall into two categories: 867 extensor and 47 flexor tendon ruptures. The localisation of the lesions is most often distal. The extensor tendon lesion is accompanied more often by a ruptured bony fragment; the distal flexor tendon is mostly torn-off bony fragment. The extensor tendon ruptures can be subdivided as follows: distal injuries of the extensor aponeurosis in the DIP joint (751 cases), IP joint (31), tractus intermedius (27), ext. carpi radialis longus (5) and brevis (1), ext. carpi ulnaris (6); proximal ruptures of the ext. pollicis longus (42), ext. digitorum communis II and indicis (1 each) and ext. carpi radialis longus and brevis (1 each). The flexor tendon lesions are as follows: distal injuries to flex. digitorum profundus (32 cases), flex. pollicis longus (9), and the opponens pollicis, which is classified under this heading (2). Proximal lesions to flex. pollicis longus (2) and flex. digitorum profundus and superficialis (1 each).     

Comparison of modified Kessler tendon suture at different levels in the human flexor digitorum profundus tendon and porcine flexors and porcine extensors: an experimental biomechanical study

This study compared the biomechanical behaviour of repairs in the human flexor digitorum profundus tendon in zones I, II and III with repairs of different segments of the porcine flexor tendon of the second digit and the extensor digiti quarti proprius tendon, in order to assess the validity of porcine tendons as models for human flexor tendon repairs. These porcine tendons were selected after comparing their size with the human flexor digitorum profundus tendon. The tendon repairs were done in three segments of each porcine tendon and repairs in the human tendons were done in zones I,II and III. Ten tendons in each group yielded a total of 90 specimens. A modified Kessler repair was done with 3-0 coated braided polyester suture and subjected to uniaxial tensile testing. In human flexor tendons, the ultimate force was higher in zones I and II than in zone III. The porcine flexor digitorum profundus tendon from the second digit and the proximal segment of the extensor digiti quarti proprius tendon behaved similarly to the human flexor tendon in zone III and can be considered as surrogates for the human flexor tendon.     

Twenty-five-year follow-up evaluation of an active silicone/Dacron tendon interposition prosthesis: A case report

A 19-year-old man sustained a severe avulsion wound of the dominant distal forearm, dividing the radial and ulnar arteries, median and ulnar nerves, and all flexor tendons. Initial treatment consisted of revascularization. Shortly thereafter he had sural nerve grafting of the median and ulnar nerves. This was followed by insertion of a silicone/Dacron tendon interposition prosthesis to reconstruct a 4-cm deficit in the flexor profundus tendons and the flexor pollicis longus tendon. Six weeks thereafter an opposition transfer using the extensor indicis proprius and a Brand type 2 intrinsic transfer using the extensor carpi radialis longus and a plantaris tendon graft were performed. Several months later an attempt was made to remove the prosthesis. It was encased in scar tissue, however, and left in place. Evaluation 25 years later revealed that the flexor tendons and prosthesis were functioning well.     

Tensile strength of a new suture for fixation of tendon grafts when using a weave technique

PURPOSE: To evaluate a new corner stitch construct for tendon graft or tendon transfer fixation and compare the tensile strength with a conventional central cross-suture design in human cadaver tendons. METHODS: Flexor digitorum profundus tendons of the index, middle, and ring fingers (48 total) were used as recipients and palmaris longus, extensor indicis proprius, and extensor digitorum communis tendons of the index finger (48 total) were used as grafts from 16 fresh-frozen human cadaver hands. We compared the cross-stitch technique with a new corner stitch technique in tendon repairs made with 1, 2, or 3 weaves (8 per group). Tendons were sutured at each weave with either 2 full-thickness cross-stitches or 4 partial-thickness corner stitches of 4-0 nylon. Mattress sutures also were placed through the free tendon end for each repair type. The tensile strength of the tendon-graft composite was measured with a materials testing machine. RESULTS: The tensile strength of the repairs increased significantly with the number of weaves. When 2 or 3 weaves were used with the corner stitch or when 3 weaves were used with the cross-stitch, the repairs were significantly stronger. Although no significant difference in strength to failure was noted when comparing cross and corner stitches with equivalent numbers of weaves, qualitatively there was a difference in mode of failure with the 3-weave corner stitches failing primarily by intrasubstance tendon failure and the 3-weave cross-stitch repairs failing by tendon pullout. CONCLUSIONS: The corner stitch is as strong as conventional cross-stitch repairs and its superficial placement may be more favorable to tendon blood supply. This repair may be advantageous for clinical applications.     

Flexor tendon gliding in the hand. Part I. In vivo excursions

The amplitude of gliding of the flexor tendons was measured in 36 hands tagged intraoperatively with buried wire sutures. Finger and wrist position was correlated with tendon excursion as measured on radiographs in the postoperative period. With the wrist in the neutral position, the superficialis tendon achieved an excursion of 24 mm and the profundus tendon 32 mm. Excursion of the flexor pollicis longus tendon was 27 mm. With wrist range of motion, the amplitude of the superficialis tendon became 49 mm, the profundus tendon 50 mm, and the flexor pollicis longus tendon 35 mm.     

Pulley plasty versus resection of one slip of the flexor digitorum superficialis after repair of both flexor tendons in zone II: a biomechanical study

BACKGROUND: The outcome of repair of zone-II lacerations of the flexor digitorum superficialis and flexor digitorum profundus tendons remains suboptimal. We investigated the effects of two strategies to improve postoperative gliding in a human cadaveric hand. METHODS: The second, third, and fourth digits were harvested from ten fresh-frozen human cadaveric hands. Complete lacerations and repairs were made to the profundus and superficialis tendons at a location where both repair sites would pass beneath the A2 pulley with the proximal interphalangeal joint in 45 degrees of flexion. The gliding resistance of the flexor digitorum profundus tendon was measured following pulley plasty and following excision of one slip of the flexor digitorum superficialis. The breaking strength of the remaining slip of the flexor digitorum superficialis tendon was then measured. RESULTS: Pulley plasty and resection of one slip of the flexor digitorum superficialis tendon both significantly decreased gliding resistance compared with repair of both slips (p < 0.001). There was no difference in the mean gliding resistance between the pulley plasty and one-slip resection groups. The flexor digitorum superficialis slip was stronger after repair with a Becker suture (28.8 +/- 9.0 N) than after repair with a modified Kessler (16.4 +/- 4.5 N) or a zigzag suture (15.0 +/- 5.7 N). CONCLUSION: Both pulley plasty and resection of one slip of the flexor digitorum superficialis reduce gliding resistance after tendon repair in zone II of the hand.     

Flexor tendon rupture caused by gout: a case report

We present a case of primary gouty infiltration of flexor tendons in the hand, causing rupture of both flexor digitorum superficialis and profundus tendons in a single digit. The patient was managed by a single-stage reconstruction of the less involved flexor digitorum superficialis tendon using a segment of the proximal stump of flexor digitorum profundus tendon as a bridge graft. This uncommon etiology of tendon rupture should be considered in all patients with a history of gout presenting with tendon insufficiency.     

Extensor tendon rupture associated with Smith's fracture. A case report

A 14-year-old boy sustained closed rupture of the extensor digitorum communis, extensor pollicis longus, and extensor indicis proprius tendons following a volarly displaced Salter-Harris Type II fracture of the distal end of the radius. The condition was treated with tendon grafts, but some limitation of metacarpophalangeal flexion remained.     

Functional absence of flexor digitorum superficialis to the little finger and absence of palmaris longus--is there a link?

We examined 150 men and 150 women aged 18-40 years to assess flexor digitorum superficialis function to the little finger and the incidence of palmaris longus absence. All patients had flexor digitorum superficialis function to the little finger assessed by standard and modified tests. The presence or absence of palmaris longus was assessed by clinical inspection. Following modified testing, ten subjects (14 hands) displayed absolute superficialis deficiency to the little finger. Forty-nine subjects had unilateral absence of palmaris longus (16%). This tendon was absent bilaterally in 26 subjects (9%). On combining the clinical findings, one subject had unilateral absence of flexor digitorum superficialis function to the little finger with contralateral absence of palmaris longus, and one subject had bilateral absence of flexor digitorium superficialis function with unilateral absence of palmaris longus. We conclude that there is no link between an absent little finger flexor digitorium superficialis and an absent palmaris longus.     

Flexor digitorum profundus common to thumb and index finger, associated with a post-traumatic distal adherence of both tendons

The existence of connections, in the form of tendon slips, between the tendons of the flexor pollicis longus and the flexor digitorum profundus indicis has been described by different authors as being a relatively frequent anomaly. Complete fusion between the two muscles, however, must be considered a very rare anomaly. A bilateral case is described, in which the right hand also had post-traumatic adhesions between the two tendons.     

Zone 2 flexor digitorum profundus and superficialis rupture treated with single-stage tendon reconstruction using an Active Hunter Rod Implant

To our knowledge, no report has been published of a flexor tendon rupture as a result of a closed phalangeal fracture.A 58-year-old woman with multiple medical comorbidities presented with a closed, apex volar fracture of her long finger proximal phalynx with clinically intact flexor digitorum profundus and superficialis tendons in zone 2 of the flexor tendon sheath. After 5 weeks of nonoperative treatment, the patient reported hearing a pop in her finger, and clinical findings suggested rupture of the flexor digitorum profundus and superficialis tendons. Intraoperatively, the nonreparable attritional rupture was underneath the A2 pulley. A bony prominence in the tendon sheath floor from the healed phalynx fracture made rerupture a concern with a tendon graft. A Hunter Active Tendon Implant (Wright Medical Technology, Inc, Arlington, Tennessee) was used to reconstruct the flexor digitorum profundus tendon to avoid a second procedure. The patient progressed well and had regained a functional arc of active finger range of motion by 2 months postoperatively.The Hunter Active Tendon Implant provided a suitable alternative to a 2-staged procedure, with the added benefit that a good tendon bed was developed in the event that a second procedure was needed.     

Ruptures of flexor tendons at the wrist as a complication of fracture of the distal radius.

We report two cases of rupture of flexor tendons after fracture of the distal radius. The first case was a rupture of the flexor digitorum profundus and superficialis tendon to the index finger that happened 20 years after the fracture. The second was a rupture of the flexor pollicis longus tendon that occurred two years after, and the flexor profundus tendon to the index finger that occurred four years after the fracture. In the first case, the ruptures were caused by the bony protuberance of the radius after long interval without interference of the ulnar head.     

Ruptures of Flexor Tendons At the Wrist as a Complication of Fracture of the Distal Radius

We report two cases of rupture of flexor tendons after fracture of the distal radius. The first case was a rupture of the flexor digitorum profundus and superficialis tendon to the index finger that happened 20 years after the fracture. The second was a rupture of the flexor pollicis longus tendon that occurred two years after, and the flexor profundus tendon to the index finger that occurred four years after the fracture. In the first case, the ruptures were caused by the bony protuberance of the radius after long interval without interference of the ulnar head.     

Subkutaner Sehnenabriss des M. flexor digitorum profundus

The diagnostic and treatment of a closed avulsion of the flexor digitorum profundus muscle at its insertion of the little finger is presented. This happened as a 41-year-old woman wanted to hold a dog lead in her left hand and suddenly the dog started to run. In the literature the flexor digitorum profundus (FDP) and flexor pollicis longus (FPL) tendons were found to be more frequently ruptured than the flexor digitorum superficialis tendon. Closed ruptures of the FDP have been rarely reported. In the case described here there was no torn fragment at the distal end of the FDP tendon and the bone structure of the phalanx distales was intact. The operative treatment, postoperative care and clinical course are presented.     

Flexor Tendon Problems after Volar Plate Fixation of Distal Radius Fractures

Four cases of flexor tendon problems which developed after volar plate fixation of distal radius fractures are presented. All cases were associated with close contact of the screws or distal edge of the plate with the flexor tendons. Poor bone stock or multiple bone fragments allowing loosening of the plate or non-locking screws cause the hardware to irritate the flexor tendons and ultimately lead to rupture. The flexor tendons involved include the flexor carpi radialis, flexor pollicis longus and flexor digitorum superficialis, and flexor digitorum profundus to the index and long fingers.     

The centralization of extensor tendons during wrist surgery

After a wrist surgery in patients with rheumatoid arthritis, the extensor tendons have a tendency to shift toward the ulnar side of the wrist. This is caused by the dorsal tenosynovectomy, disruption of extensor retinaculum, and exteriorization and anatomical orientation of the superficial group of forearm extensor tendons. This article describes a technique as an adjunct to the wrist surgery, which aims to stabilize and centralize tendons of the fourth dorsal wrist compartment over the midline of the wrist. This is achieved by creating a distally based sling, harvested from the extensor carpi radialis longus tendon, then wrapped around the extensor digitorum communis and the extensor indicis proprius tendons, and finally anchored onto the extensor carpi radialis brevis. This adjunctive procedure is recommended in situations when after the wrist surgery, particularly wrist arthroplasty, tendons of the fourth dorsal wrist compartment tend to lay ulnar to the central axis of the hand.     

Neglected flexor tendon injury for 10 years,un-usual finding and one stage repair without free tendon graft: Case report

IntroductionIn delayed or neglected cases of flexor tendon injury, reconstruction of flexor digitorum profundus (FDP) is usually performed using free tendon graft due to the retraction of tendon ends and shortening of the tendon. Flexor digitorum superficialis (FDS), palmaris longus or plantaris tendons can be used as a free tendon graft [1–3].Presentation of caseThis is a case report of female patient 17 years old with neglected cut of her left Ring finger's FDP and FDS tendons zone II with suspected concomitant digital nerve injury, the injury was neglected for 10 years in the patient's non-dominant hand.DiscussionUpon exploration unusual finding of spontaneous healing of the proximal stumps of FDS and FDP tendons raised the idea of doing the repair one stage without free graft by using pedicled intra-synovial graft from the sublimis tendon to reconstruct the FDP tendon.The patient after 4 months follow-up and after completion of the physiotherapy program regained the ability to actively flex her finger to near full flexion with improved function and cosmesis.ConclusionDelayed flexor tendon reconstruction in neglected cases is still offering good results even after long periods of delay provided that the finger's joints are still supple and mobile.