A prospective study of flexor tendon repair in zone 5

A prospective study of postoperative mobilization of flexor tendon repairs in zone 5 was conducted over a 2-year period between 1994 and 1996 using a controlled active motion (active extension-active flexion) regimen of mobilization. Fifty-two patients, who had a total of 151 flexor digitorum superficialis (FDS) and 103 flexor digitorum profundus (FDP) divisions, were available for review at a mean follow-up of 10 months. Of the 161 fingers with division of one or both flexor tendons, 66% exhibited independent FDS function and 90% achieved good or excellent results of digital range of motion. No rupture of an FDP tendon repair occurred during the study period. The data allowed us to define a new method of classifying the results of treatment of these injuries in terms of the injured wrists as a whole and not simply as a series of isolated observations for each individual finger with divided flexor tendons. The results of recovery of independent FDS action and range of finger movement achieved for injuries in which the flexors of all four fingers had been divided indicate a statistically significant interdependence of injuries of finger flexors of adjacent fingers at the wrist. Multivariate analysis showed the presence of a "spaghetti wrist" injury to have a significant adverse effect on the recovery of the independent FDS action but not on the recovery of the digital range of motion.     

Closed ruptures of the flexor digitorum tendons: MRI evaluation

OBJECTIVE: To assess the MRI findings in cases of closed rupture of the flexor digitorum tendons (FDT). PATIENTS AND DESIGN: Ten patients with a clinical suspicion of rupture of FDT underwent MRI before surgery. None of the patients presented a skin injury. Fingers were imaged using axial T1-weighted SE sequences, three-dimensional GE images, and curved reconstructions. RESULTS: Twelve FDT had surgical confirmation of rupture. Flexor digitorum profundus (FDP) and flexor pollicis longus (FPL) tendons were more frequently ruptured (n=8) than flexor digitorum superficialis (FDS) tendons (n=4). MR images accurately depicted the level of the rupture. The gap between the tendon ends (mean 45 mm, range 21-70 mm) was assessed best with curved reconstructions and was well correlated with the surgical findings. The proximal end mainly retracted into the palm or the carpal tunnel (n=8), and less frequently into the digital canal (n=4). In two cases, the proximal end curled up in the palm, clinically simulating a rupture of a lumbrical muscle in one case. MRI also showed the appearance of the adjacent tendons. CONCLUSION: MRI accurately depicted the level of rupture and the gap between the tendon ends, which assisted the surgical choice between suture, graft or tendon transfer.     

Early active mobilization of tendon grafts using mesh reinforced suture techniques

The flexor digitorum profundus tendon in 11 digits with division of both flexor tendons in zone 2 was reconstructed with a palmaris longus tendon graft in a two-stage procedure. The distal and proximal fixation of the graft was reinforced with a polyester mesh sleeve placed around the ends of the graft during stage 1. All digits were mobilized with a combination of active extension and active and passive flexion within 3 days of the second stage. There were three ruptures, one due to faulty technique and two due to falls on outstretched hands during alcohol intoxication and football. Excluding the ruptures, the mean active composite distal and proximal interphalangeal joint range of motion 6 weeks and 6 months post-operatively was 141 degrees and 136 degrees respectively. The results indicate that palmaris longus tendon grafts can survive and heal during early active mobilization, with few or no adhesions of functional significance. The techniques described here represent one possible approach to the safe implementation of early active mobilization after tendon grafting procedures.     

Cyclic testing of flexor tendon repairs: an in vitro biomechanical study

Forty cadaveric flexor digitorum profundus tendons were repaired using the Tajima, Halsted, Silfverskiold, or Savage techniques. The tendons were cyclically loaded in sets of 4,000 cycles beginning at 25 N and increasing by 10-N increments until failure occurred. Gap formation was continuously monitored with an extensiometer. Only the Savage repair group consistently withstood 4,000 cycles of 25-N loading, with respect to 2-mm gap formation and repair rupture. Tendon repairs subjected to cyclic loading demonstrated gap formation and repair rupture at lower loads than with static testing. Of the methods of flexor tendon repair tested, only the Savage technique could withstand simulated early active motion.     

Black Creek Canal Virus infection in Sigmodon hispidus in southern Florida

Flexor pulleys in the hindpaw digits of twenty-eight adult mixed-breed dogs were reconstructed in order to investigate the influence, on the reconstruction, of the source of the autogenous tissue (intrasynovial compared with extrasynovial tendon) and the tension applied during the repair. The ipsilateral peroneus longus tendon was used to reconstruct the A2 pulley with an around-the-bone technique in twenty-one digits; the graft was sutured at a tension of 0.49, 0.98, and 1.96 newtons in seven digits each. The flexor digitorum profundus tendon of an adjacent digit was used to reconstruct the A2 pulley, at a tension of 0.98 newton, in seven additional digits. The contralateral digits were used as controls for all twenty-eight treated digits. The digits were tested in a custom apparatus designed to measure the frictional force generated between the reconstructed pulley and the tendon beneath it. The frictional force did not differ significantly (p > 0.5) among the three groups repaired with peroneus longus tendon; however, the average value was more than five times that produced in the contralateral, control digits. The average frictional forces created by the flexor digitorum profundus grafts were similar to those in the contralateral, control digits. Reconstruction with the flexor digitorum profundus at a tension of 0.98 newton produced significantly less frictional force (p < 0.05) than that produced by the peroneus longus graft at the same tension. This in vitro model of reconstruction of the A2 pulley demonstrated that tendon from an intrasynovial source (the flexor digitorum profundus) produced less frictional resistance to gliding of the tendon than did tendon from an extrasynovial source (the peroneus longus). This result is consistent with previously published findings that intrasynovial tendons may make better grafts than extrasynovial tendons for the reconstruction of gliding flexor tendons because of decreased friction and better healing qualities. Intrasynovial tendons may also make better grafts for the reconstruction of flexor pulleys.     

Experimental study on the effects of tension-reduced early mobilization on extensor tendon healing

Numerous clinical and experimental studies have been reported on early postoperative mobilization after flexor tendon repair. However, there have been only a few experimental studies reported on extensor tendon repair. In 1989, Ishiguro reported the usefulness of tension-reduced early mobilization in clinical cases of extensor tendon ruptures. The purpose of this experimental study was to examine the in vivo effect of tension-reduced early mobilization on extensor tendon healing in chicken. An experiment was performed on the extensor tendons of 218 chickens in an attempt to examine the effects of tension-reduced early mobilization on tendon healing and adhesion. The extensor tendon of the fourth toe was cut and the distal stump of the tendon was transferred to the extensor tendon of the third toe. Postoperatively two protocols were employed. In the immobilization group, a cast was applied for three weeks. In the early-mobilization group, immediate active motion of the digits was allowed. A tension-reduced position was maintained by taping the fourth toe to the dorsum of the third. The findings from the early mobilization group and from the immobilization group were as follows: 1. Macroscopically, sutures at the repair site of the early-mobilized tendon were not evident after three weeks because of fibrous connective tissue growth. Despite this abundant connective tissue, tendon gliding was observed to be smooth. Between the suture site and the gliding floor, loose connective tissue, similar to normal paratenon, was observed. Histology confirmed this observation. 2. The tensile strength required to extend the MP joint was significantly lower for the early-mobilization group than for the immobilization group, suggesting minimal adhesion between the sutured tendon and the gliding floor in the early-mobilization group. 3. No significant difference in tensile strength among the various tendon repair techniques employed was observed at the suture site.     

Advances in perfusion MR imaging

This case report describes a complication that occurred following long and ring finger flexor digitorum superficialis tendon transfers routed around the ulnar border of the forearm to restore digital extension. An ulnar mononeuropathy developed in the early postoperative period that was characterized by decreased ring and small finger sensation and interosseous muscle weakness. Operative exploration demonstrated extrinsic compression of the ulnar nerve by the long and ring finger flexor digitorum superficialis tendons. When superficialis tendon transfers are chosen to restore digital extension, passage around the radial side of the forearm or through the interosseous space are recommended to avoid this potential complication.     

Tensile strengths of various suture techniques

The tensile strengths of various suture techniques were studied in vitro using rabbit Achilles' and flexor digitorum longus tendons. Two new suture methods, a Double and Triple (modified) Kessler, were compared with the Savage, Indiana and modified Kessler techniques. All were core sutures without epitendinous sutures. All suture techniques were found to be significantly different for 2 mm of gap formation. The study found the Savage technique strongest, followed by the Triple Kessler, the Double Kessler, and finally the Indiana. The Double Kessler was almost twice as strong as the modified Kessler. This study also compared two four-stranded techniques (the Indiana and Double Kessler) and found the Double Kessler stronger. The Double Kessler is a simple yet strong suture and may be useful for flexor tendon repairs.     

The vascularization of the common synovial sheath and the tendons of the flexor muscles of the carpal tunnel

The detailed anatomy of the tendon apparatus, the blood supply of the superficial (FDS) and profundus (FDP) flexor muscles and the blood supply of the common synovial sheath in the carpal tunnel were studied on 200 hundred upper extremities from fresh human cadavers. The injection of coloured latex or the aqueous solution of India ink and gelatin revealed a complex arterial network. Dissection of the carpal tunnel revealed the existence of different sources of the blood supply of the tendons of the flexor muscles and carpal sheath. The different sources and zones of vascularization are described. This study concerns the synovial and tendinous apparatus of the flexor muscles as well as their blood supply in the carpal tunnel. These data may be of interest hand surgeons.     

The vascularization of human flexor tendons within the digital synovial sheath region--structureal and functional aspects

The intrinsic vascularization of human flexor tendons within the digital sheath region was studied on fresh amputation specimens with the aid of angiographic and histochemical techniques. In the flexor digitorum profundus tendon, three separate vascular systems of various origin and with no or very little communication could be verified. In the flexor digitorum superficialis tendon, two such systems were observed. The volar surface of both tendons is more or less devoid of vessels. Moreover, at the proximal interphalangeal joint level, the flexor digitorum profundus tendon has a volar avascular zone, constituting about 1 mm, i.e., about one-third to one-fourth of the thickness of the tendon. It is assumed that the synovial fluid is of importance for the nutrition of the tendons and that therefore the synovial sheath should be preserved as much as possible.     

Biochemistry and biomechanics of healing tendon: Part II. Effects of combined laser therapy and electrical stimulation

Twenty-two closed Achilles tendon ruptures caused by sports injuries in 22 patients (average age, 37.6 years) were repaired with Kirschmayer core suture and cross-stitch epitenon suture, and early active ankle motion with weightbearing was implemented after surgery. This study was undertaken to evaluate the effectiveness of the repair technique and rehabilitation protocol by assessing clinical results and magnetic resonance imaging findings. The follow-up period averaged 24.6 months. Twenty of the tendons (91%) healed without rerupture, and two tendons (9%) suffered a partial rerupture at 23 and 56 days, respectively. Active ankle extension reached from the minus range to 0 degree in an average of 9.7 days, and ankle motion recovered to normal in an average of 6.0 weeks. Full weightbearing without heel raising became possible in an average of 16.4 days, and heel raising with both legs became possible in an average of 7.3 weeks. The patients returned to full sports activity in 13.1 weeks. The interval until the area of high-intensity signal at the tendon repair site on T2-weighted magnetic resonance imaging scans became intermediate-intensity signal averaged 6.9 weeks, and the tendon repair site became low-intensity signal in an average of 12.6 weeks, demonstrating excellent tendon healing. Treatment employing Kirschmayer core suture and cross-stitch epitenon suture may help athletes return to sports activity in a shorter period than that allowed by previous methods of repair for Achilles tendon ruptures.     

Tendon repair by laser welding: a histologic and biomechanical comparison and suture repair with CO2 and argon lasers

BACKGROUND AND OBJECTIVE: The purpose of this study was to determine whether welding of tendinous tissue is possible with the application of thermal lasers. STUDY DESIGN MATERIALS AND METHODS: After sharp transection of a unilateral achilles tendon, 40 male outbred Spraque Dawley rats were divided equally between four treatment groups. Ten animals underwent repair using the modified Kessler suture technique. The remaining animals underwent application of laser after the tendon edges were reapproximated and held in place with a vascular clamp. CO2 and Nd:YAG lasers were applied using 25% human albumin as a solder. Fluorescein dye was added to albumin and used as solder for the Argon laser. Biomechanical and histologic testing were performed immediately and 14 days postoperatively. RESULTS: Argon and CO2 lasers successfully fused the tendon ends together. However, immediately postoperative, the resultant tissue weld was tenuous and conventional tensile strength testing was not possible. At 14 days postoperatively, all modes of tendon repair resulted in tensile failure at consistently lower levels of tension than those required for the normal uninjured tendons. The ultimate tensile strength for the suture-repaired, CO2 laser welded, and Argon laser welded tendons were 74%, 59%, and 64% of the strength of the control tendons respectively. No statistically significant difference was found in the tensile strength among the three repair groups. Histologic evaluation at 14 days revealed the greatest degree of inflammatory response in those tendons repaired with the Argon laser. Those tendons repaired with suture demonstrated the least amount of inflammatory change. CONCLUSION: Our study demonstrates that welding of a tendon is possible with the application of laser energy. However, we were unable to produce a weld sufficient to withstand significant tensile loads in the immediate postoperative period.     

Molecular studies in flexor tendon wound healing: the role of basic fibroblast growth factor gene expression

Basic fibroblast growth factor (bFGF) is a cytokine that plays a fundamental role in angiogenesis. This study examines bFGF messenger RNA (mRNA) expression in a rabbit flexor tendon wound healing model. Thirty-four New Zealand white rabbit forepaws underwent transection and repair of the middle digit flexor digitorum profundus tendon in zone II. Tendons were harvested at increasing time intervals and analyzed by in situ hybridization and immunohistochemistry. Few tenocytes and tendon sheath cells expressed bFGF mRNA in unwounded tendons. In contrast, tendons subjected to transection and repair exhibited an increased signal for bFGF mRNA in both resident tenocytes concentrated along the epitenon and infiltrating fibroblasts and inflammatory cells from the tendon sheath. These data demonstrate that (1) normal tenocytes and tendon sheath cells are capable of bFGF production, (2) bFGF mRNA is upregulated in the tendon wound environment, and (3) the upregulation of this angiogenic cytokine occurs in tenocytes as well as in tendon sheath fibroblasts and inflammatory cells.     

Tendon transfer for equinovarus deformed foot caused by cerebrovascular disease

Surgical correction was performed on 125 patients who had equinovarus deformity caused by a cerebrovascular accident and who needed an ankle foot orthosis for walking. The operative procedures involved anterior transfer of the long toe flexors (flexor hallux longus and flexor digitorum longus; long toe flexor group) or lateral transfer of the anterior tibial tendon (anterior tibial tendon group), combined with lengthening of the Achilles tendon. On evaluation more than 2 years after surgery, 83 of 110 patients of the long toe flexor group and eight of 15 patients of the anterior tibial tendon group were able to walk without a brace. Five patients of the anterior tibial tendon group who had shown strong contraction of the anterior tibial muscle during the swing phase before surgery, needed a brace because of a drop foot after surgery. Thus, lateral transfer of the anterior tibial tendon was abandoned in 1984. Recurrence of varus deformity was seen in approximately 15% of the patients in both groups. Anterior transfer of the long toe flexors, using them as dorsiflexor tendons or for tenodesis, seemed to produce better results.     

The effect of ribosome-inactivating proteins on the ribosome from the hyperthermophilic archaeon Sulfolobus solfataricus

Ten cadaver digits were used to evaluate excursion resistance between a tendon and pulley after completing 4 methods of pulley reconstruction (Bunnell's, Kleinert's, Lister's, and Karev's techniques). Five tissues (palmaris longus tendon, extensor digitorum tendon, flexor digitorum superficialis tendon, extensor retinaculum, and volar plate) were used to reconstruct the A2 pulley. Intrasynovial tissue sources (extensor retinaculum, volar plate, and flexor digitorum superficialis tendon) produced less excursion resistance than extrasynovial tissue sources (extensor digitorum tendon and palmaris longus tendon). The models using the extensor retinaculum and volar plate as reconstructive materials produced less excursion resistance than the normal A2 pulley, whereas the models using the palmaris longus tendon produced the highest excursion resistance. Bunnell's technique of pulley reconstruction produced less excursion resistance than Kleinert's technique with all 3 tissues tested. The results of the in vitro study of excursion resistance between the tendon and reconstructed pulley demonstrated that Lister's technique of pulley reconstruction using the extensor retinaculum produced the least resistance to tendon gliding.     

Division of flexor tendons causes progressive degradation of tendon matrix in rabbits

Deep flexor tendons of 30 rabbits were divided at the ankle level. The effects of unloading on the synthesis and content of matrix components, the synthesis of DNA, and dry weight were investigated. The ability of the tendons to synthesize collagen during short-term culture and the contents of matrix components decreased inversely to the time of unloading. 12 weeks following division, the fibrocartilagnious segments had lost 2/5 of their dry weight, 2/3 of proteoglycan and 1/3 of collagen and non-collagen protein content. Less pronounced losses were observed in the non-fibrocartilaginous segments. A transient increase in cell proliferation in both types of segments was found. These findings indicate that divided flexor tendons undergo a progressive degradation, degradation, which may have implications for delayed suture of deep flexor tendon injuries.     

Impact of d-amphetamine on temporal estimation in pigeons tested with a production procedure

The use of pedicled flexor digitorum superficialis tendon as a tendon graft in the second stage of flexor tendon reconstruction has the advantage of employing local intrasynovial tendon graft and allowing early active range of motion. This method of staged flexor tendon reconstruction was used in 47 patients between 1983 and 1993. Thirty-three patients were evaluated 1 year or longer after the second stage of surgery. The follow-up period averaged 3.7 years. Sixty-four percent of the injuries were in zone II, and 30% were Boyes grade V in severity. Good to excellent results were achieved in 64% of patients. Three patients needed graft tenolysis. Postoperative persistent flexion contractures ranging from 8 degrees to 55 degrees of the proximal interphalangeal or distal interphalangeal joints or both were present in 88% of patients. Several factors that influenced the final outcome were identified: age over 25 years, zone II injuries of Boyes grade V, and the lack of a regular postoperative rehabilitation program were associated with relatively less successful final results.     

The differential effect of personality on computer-based treatment of agoraphobia

A case of index flexor digitorum profundus and median nerve entrapment by bony fracture after reduction as a complication of distal radial fracture in an 11-year-old male is described. After release of tendon and nerve the patient had a good functional result.     

Injuries of the flexor tendons of the hand

Diagnosis of clear-cut severing of the two flexor tendons is simple and obvious. This is not true for isolated injury to a single tendon and for partial severing. In this case, careful clinical examination and routine surgical exploration of any wound with regard to the course of the flexor tendon is required. Surgery should aim at the least traumatic repair possible, followed by specialised rehabilitation directed by the surgeon. In the distal region, reinsertion into the bone is required. In other regions, suture consists of a the main suture with a continuous suture of the epitendineum. The region of the digital canal requires rigourous care due to its specific anatomy. The corollary to good surgical repair is rehabilitation, understood and complied with by the patient. Early mobilisation procedures are used predominantly in order to avoid the formation of postsurgical adherences.     

Hand flexor tenosynovitis in rheumatoid arthritis. Prevalence, distribution, and associated rheumatic features

Tenosynovitis of one or more flexor tendons of the hand (mean 3.1 tendons per patient) was noted in 55% of 100 patients with rheumatoid arthritis (RA) examined periodically during a mean period of 5 years. The third flexor tendon was involved most frequently (71% of patients), followed by the second (62%), fourth (53%), fifth (27%), and first (13%). Patients with flexor tendonitis (FT) had a significantly higher prevalence of rheumatoid nodules (56% vs 33%), carpal tunnel syndrome (47% vs 13%), wrist extensor tenosynovitis (47% vs 9%), and elbow epicondylitis (22% vs 7%) than patients without FT. Dupuytren's contracture, DeQuervain's tenovaginitis, flexor carpi radialis and ulnaris tendonitis, and Achilles tendonitis were found exclusively in patients with FT. A control group of 50 non-RA patients with FT had statistically fewer diseased tendons per patient (mean 1.5) and a different digital distribution, the thumb being affected more frequently (P less than 0.05) than in RA patients.