The fate of autogenous tendon grafts

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Endoscopic carpal tunnel release: an anatomic study of the two-incision method in human cadavers

To determine the relationship of neurovascular structures to the sites of portal placement and transverse carpal ligament division during two-portal endoscopic carpal tunnel release, a study of 20 fresh cadaver specimens was carried out. Open dissection of the carpal tunnel after endoscopic surgery showed complete ligamentous release in 18 hands (90%). In 10 specimens, the procedure was performed as described by Chow. There was one partial transection of the superficial palmar arch (5%), and five specimens (50%) had complete divisions of the superficial palmar fascia with considerable pressure placed on the ulnar nerve at the wrist. A modified technique was used in 10 specimens in which the proximal incision was made in a more distal location and a distally based ligamentous flap was created. The superficial palmar arch and the distal edge of the transverse carpal ligament were visualized directly before passage of the trocar. No complications were noted with this method.

Angiogenesis in healing autogenous flexor-tendon grafts

On the basis of recent evidence that flexor tendon grafts may heal without the ingrowth of vascular adhesions, eighteen autogenous donor tendons of intrasynovial and extrasynovial origin were transferred to the synovial sheaths in the forepaws of nine dogs, and controlled passive mobilization was instituted early in the postoperative period. The angiogenic responses of the tendon grafts were determined with perfusion studies with India ink followed by cleaing of the tissues with the Spalteholz technique at two, four, and six weeks. A consistent pattern of neovascularization was noted in the donor tendons of extrasynovial origin. Vascular adhesions arising from the flexor digitorum superficialis and the tendon sheath enveloped the tendon grafts by two weeks. By six weeks, the vascularity of the tendon grafts of extrasynovial origin appeared completely integrated with that of the surrounding tissues. Examination of cross sections revealed that the segments of tendon had been completely vascularized by obliquely oriented intratendinous vessels. In contrast, the flexor tendon grafts of intrasynovial origin healed without ingrowth of vascular adhesions. Primary intrinsic neovascularization took place from the proximal and, to a lesser extent, distal sites of the sutures. Examination of cross sections revealed vessels extending through the surface layer of the tendon graft, with small vessels penetrating the interior of the tendons at regular intervals.

Intrinsic mitogenic potential of canine flexor tendons

Recent studies have demonstrated an intrinsic neovascular response in intrasynovial healing tendons, introducing the possibility of mitogenic and/or angiogenic capability of intrasynovial tendon. To explore this hypothesis, healing canine flexor tendons were treated with early passive mobilization and the repair sites analysed at three, ten and 17 days. Specimens were mechanically digested and subjected to a standard BALB/c 3T3 mitogenic assay, which measures the capacity of tissue extracts to induce DNA synthesis and cell division in fibroblasts. Results revealed that both control and repaired flexor tendons possessed mitogenic activity, with the greatest activity observed in control specimens. Decreasing activity was noted as the time between repair and analysis increased. These data provide increasing evidence for the flexor tendon's active role in the healing process, and support the concept that mitogenic or growth-promoting factors are associated with flexor tendons and may be released following injury, during the early stages of healing.

Genetic expression for type I procollagen in the early stages of flexor tendon healing

To determine the precise mechanism by which contact tendon healing occurs at the cellular level, the production of pro alpha (I) collagen messenger RNA (mRNA) produced by fibroblasts of healing intrasynovial flexor tendons was determined by an in situ hybridization technique. The repair site and the proximal and distal tendon stumps of repaired tendons treated with early controlled passive mobilization were fixed and buffered in formalin, 3, 7, 10, and 17 days after repair. A complimentary DNA (cDNA) probe corresponding to alpha (I) procollagen mRNA was labeled with [32P]d-CTP. After hybridization, autoradiography, and staining of the sections, the level of procollagen mRNA was assessed by microscopic examination. Rising levels of procollagen mRNA, indicating progressively increasing levels of synthetic collagen activity, were detected in the healing tendons through 10 days. A moderate decrease in procollagen mRNA was seen at 17 days. Genetic expression for procollagen mRNA was localized specifically to the epitenon cells on the tendon surface overlying the repair site and to cells in the gap between the tendon stumps. No detectable expression was noted in endotenon fibroblasts. The finding of high levels of expression for procollagen type I mRNA in the surface layer of healing tendons demonstrates that cells intrinsic to tendon epitenon contribute the greatest quantity of native tendon collagen to the repair site during these important early intervals after tendon suture.

Intercalary flexor tendon grafts. A morphological study of intrasynovial and extrasynovial donor tendons

Intercalary intrasynovial and extrasynovial flexor tendon graft donors were placed within the synovial sheaths of the medial and lateral forepaw digits of 22 dogs and treated with early controlled passive mobilization. Specimens were studied by light and transmission electron microscopy at 10 and 21 days. Early repair in the extrasynovial tendons occurred by an ingrowth of connective tissue from the digital sheath. Adhesions obliterated the gliding surface and occupied the space between the tendon's gliding surface and surrounding tissues. There was no epitenon response noted in the extrasynovial tendon grafts. While there was considerable new collagen fibril formation within the repair site at the ultrastructural level, there was a lack of longitudinal remodeling. In contrast, the intrasynovial tendon grafts showed early healing, with minimal adhesion formation, by a proliferation and migration of cells from the epitenon. These cells showed greater cellular activity and collagen production at 10 and 21 days compared to cells in extrasynovial tendons at the same intervals. The findings of this study suggest that the use of intrasynovial autogenous tendon graft donors, coupled with early controlled motion, stimulates an intrinsic repair process in both the tendon stump and autogeneous tendon graft. These findings differ significantly from the experimental findings in which extrasynovial, paratenon-covered grafts are used.

Epithelioid sarcoma in the upper extremity

Eighteen patients who had epithelioid sarcoma in the upper extremity were divided into two groups on the basis of treatment: marginal resection of the tumor or wide or radical resection of the tumor. Historical, demographic, histological, and staging data were recorded and were correlated with the type of treatment and the outcome. Marginal resection (excision through the reactive zone or pseudocapsule surrounding the tumor, with confirmation of a negative margin by a pathologist), with or without adjuvant therapy, led to a dismal outcome in patients who had been treated in this manner initially or secondarily (fifteen failures after seventeen procedures). Disease-free survival at ten years was significantly improved when wide resection (intracompartmental en bloc excision with a cuff of normal tissue of more than three centimeters) or radical resection was either the initial or the secondary treatment; success then was noted in nine of thirteen operations. Of twelve patients in whom a marginal resection had been done initially, three had had a recurrence, three had had a metastasis, and five had died, at a mean follow-up of seven years (range, twenty-seven months to sixteen years). At a mean follow-up of six years (range, two to fifteen years), only one of five patients in whom a secondary lesion had been treated with marginal resection was free of disease. Of the six patients who had been treated with wide or radical resection initially, none had died, one had had a recurrence, and one had had a metastasis, at a mean follow-up of seven years (range, twenty-two months to fourteen years).(ABSTRACT TRUNCATED AT 250 WORDS)

The utility of portable nerve conduction testing for patients with carpal tunnel syndrome: a prospective clinical study

The usefulness and accuracy of a portable instrument, the electroneurometer, for measuring distal motor latencies was determined in a prospective study of 28 patients (51 hands) with carpal tunnel syndrome and 10 controls (18 hands). There was a close correlation of distal motor latencies from the electroneurometer with those from formal electrodiagnostic testing. The average distal motor latency of controls was 3.3 +/- 0.4 msec, compared with a mean value of 5.2 +/- 1.8 msec in symptomatic hands. The sensitivity of the neurometer test alone was 69% (9 false-negatives); when combined with quantitative sensibility testing, sensitivity increased to 84%. Specificity of the neurometer test alone was 100% (no false-positives). The portable electroneurometer is a convenient, painless, inexpensive device for screening patients with carpal tunnel syndrome. Formal electrodiagnostic testing is indicated for differentiation of lesions present at different levels, for detection of subtle sensory changes, and for use in those patients in whom surface electrode usage is ineffective.

The effects of frequency and duration of controlled passive mobilization on tendon healing

This study was designed to determine the effects of frequency and duration of controlled passive motion on the healing flexor tendon following primary repair. Adult mongrel dogs were divided into two groups based on frequency of controlled passive motion. In one group, motion was applied manually at a frequency of 12 cycles/min for 5 min/day; in the other group, a continuous passive motion machine was used to apply motion at a lower frequency of 1 cycle/min for 60 min/day, making the number of cycles each day for both groups identical. Gliding function and tensile properties of repaired tendons were evaluated biomechanically at 3 and 6 weeks postoperatively. Results showed that gliding function in both groups was similar, but tensile properties, as represented by linear slope, ultimate load, and energy absorption, were significantly improved in the higher frequency group. It was concluded that frequency of controlled passive motion rehabilitation is a significant factor in accelerating the healing response following tendon repair, and higher frequency-controlled passive motion has a beneficial effect.

Fibroblast chemotaxis after tendon repair

Healing canine flexor tendons were treated with early controlled passive mobilization. The repair site and proximal and distal tendon stumps were stained for fibronectin and examined by light microscopy at three, seven, eleven, and seventeen days. Fibronectin increased dramatically in the epitenon adjacent to the repair site seven days after repair, a time when epitenon cellular activity was at its peak. By seventeen days, fibronectin staining had decreased substantially, both at the repair site and in the tendon stumps. A delayed increase in fibronectin activity was noted in the endotenon adjacent to the repair site. Fibronectin production appears to be an important component of the early tendon repair process. Fibroblast chemotaxis and adherence to the substratum in the days after injury and repair appears to be related directly to fibronectin secretion. This study is the first to provide documentation of fibronectin localization in a clinically relevant tendon repair model.

The revascularization of healing flexor tendons in the digital sheath. A vascular injection study in dogs

The role of revascularization in the nutritional support of repair of the flexor tendons is not completely understood. To explore the extent to which intrasynovial flexor tendons revascularize after transection and suture, a vascular injection study was carried out in a canine model. The tendons to the second and fifth digits of the forepaw in twelve adult mongrel dogs were transected and repaired. There were twenty-four experimental tendons and twenty-four normal tendons. The limb was placed in a polyurethane shoulder-spica cast, and the paw was treated with immediate protected passive mobilization. At three, seven, ten, seventeen, and twenty-eight days, the animals were killed and the major arteries supplying both the paw that had been operated on (left) and the contralateral normal paw (right) were injected with 200 milliliters of India ink. Segments of repaired and normal tendons were then clarified by a modified Spalteholz technique. The normal tendons demonstrated a well developed mesotenon that provided vascularization of the proximal portion of the flexor digitorum profundus tendon. A consistent three-cubic-millimeter avascular intrasynovial portion of tendon was noted. Distally, vessels arose from the vinculum breve, supplying the terminal twenty millimeters of tendon substance. In the experimental tendons, longitudinal and transverse clarified sections showed consistent revascularization of the site of repair by proximal vessels in the absence of ingrowth of peripheral adhesions. Vessels in the epitenon progressively extended for a distance of ten millimeters, through normally avascular regions, to reach the site of repair by the seventeenth postoperative day. Intratendinous vessels about the site of repair consistently originated from surface vessels, rather than from extensions of pre-existing intratendinous vessels. New vessels penetrated all areas, including the normally avascular volar segments of tendon, irrespective of previous topical zones of avascularity. Proximal vascular plexi were characterized by large tortuous vessels with frequent circuitous branches. More distal vessels had a longitudinally oriented, feathery appearance.

An experimental model for the study of canine flexor tendon adhesions

An experimental model for the study of canine flexor tendon adhesions was designed using a standardized crush-abrasion injury, meticulous sheath closure, and three-week limb immobilization. Ten animals in the experimental protocol were evaluated for visible adhesion formation. With use of a flexor tendon adhesion rating scale, consistent adhesion formation was documented with an average score of 10.4 +/- 2.1 (range, 0 to 12). Five additional animals had biomechanical testing. Applying an increasing load to the proximally divided profundus tendon (0 to 10 Newtons), it was found that the angle of distal interphalangeal joint motion and the displacement of the toe were significantly decreased, and the work generated significantly increased in the experimental versus control digits (p less than 0.05). The consistent production of visible adhesions thus correlates with biomechanical impairments in toe motion and work. The study of agents aimed at diminishing flexor tendon adhesions will thus be facilitated by this reliable model. Systemic or intrasheath administration of agents will be possible.

Slipped capital femoral epiphysis. A quantitative analysis of motion, gait, and femoral remodeling after in situ fixation

A prospective clinical study was done for quantitative examination of motion of the hip, gait, and proximal femoral remodeling after in situ fixation of a slipped capital femoral epiphysis. In situ fixation was performed in forty-five consecutively treated patients (fifty-six hips). Thirty-nine (87 per cent) of the patients returned for examination two years after treatment. The greatest percentage of motion of the hip returned within six months after treatment. Despite loss of internal rotation of the hip, the mean foot-progression angle was 10.8 degrees. Radiography and computerized tomographic scanning revealed minimum change in the relationship of the femoral head to the femoral shaft and no change in the neck-shaft angle. Motion returned despite minimum osseous remodeling. The early return of motion (in the first three months) may have been due to relief of pain, spasm, and synovitis, while soft-tissue stretching and resorption of bone in the anterolateral part of the femoral neck may have accounted for the remainder of the increase in internal rotation.

Influences of the protected passive mobilization interval on flexor tendon healing. A prospective randomized clinical study

A prospective multicenter clinical study was carried out to determine whether improved tendon gliding could be achieved with greater durations of daily passive-motion rehabilitation after flexor tendon repair. Fifty-one patients were placed randomly into two controlled passive-motion protocols. Group 1 patients received greater intervals of passive-motion rehabilitation using a continuous passive-motion device. Group 2 patients were treated with a traditional early passive-motion protocol for tendon rehabilitation. For Group 1 patients, the mean interval of controlled motion rehabilitation was 75 hours a week, and the mean number of cycles was 12,000. For Group 2 patients the mean interval of controlled passive motion was four hours a week, and the mean number of cycles was 1000. The minimum follow-up time was six months (mean, 10.8 months). Using Strickland and Glogovac's formula, the mean active motion for digits in Group 1 was 138 degrees +/- 6 degrees. Mean motion for tendons in Group 2 was 119 degrees +/- 8 degrees. The difference between Groups 1 and 2 was statistically significant. The effect of the number of tendons injured per digit within each group was not significant. The data from this experiment indicate that the duration of the daily controlled motion interval is a significant variable insofar as postrepair flexor tendon function is concerned.

Treatment of de Quervain tenosynovitis. A prospective study of the results of injection of steroids and immobilization in a splint

In a prospective study of non-operative treatment of de Quervain tenosynovitis, ninety-nine wrists of ninety-five consecutively seen patients who had this diagnosis had an injection of one milliliter of a 1 per cent lidocaine solution and one milliliter of a suspension containing forty milligrams of methylprednisolone acetate. Twelve patients (twelve wrists) were lost to follow-up. Of the remaining eighty-seven wrists, fifty-four (62 per cent) had a satisfactory outcome at a mean of eighteen months (minimum follow-up, twelve months). The duration of symptoms before treatment did not affect the outcome. The result in thirty-three wrists (38 per cent) was considered unsatisfactory. Thirty of these wrists were subsequently treated with operative release of the first dorsal compartment, and twenty-two (73 per cent) of the thirty were found to have a separate compartment for the extensor pollicis brevis. The prevalence of a separate compartment is significantly higher than that in the general population, as shown in anatomical studies of cadavera.

Healing of digital flexor tendons: importance of the interval from injury to repair. A biomechanical, biochemical, and morphological study in dogs

The effect of an elapsed interval of time between injury and operative repair of the flexor tendons was investigated in a canine model. Transected intrasynovial flexor tendons were repaired either immediately or after a delay of seven or twenty-one days. The biomechanical, biochemical, and morphological characteristics were compared at three and six weeks. The values for angular rotation, linear excursion, ultimate load, and linear slope were determined; concentrations of collagen and reducible collagen cross-links, an index of newly synthesized collagen, were measured; and the ultrastructural morphology of the tendons was examined by high-voltage electron microscopy. For the tendons that were repaired immediately, the values for angular rotation were 9.4 +/- 3.2 and 13.0 +/- 3.7 degrees at three and six weeks; for those that were repaired at seven days, 4.1 +/- 1.3 and 2.5 +/- 1.4 degrees; and for those that were repaired at twenty-one days, 2.7 +/- 0.8 and 4.7 +/- 0.7 degrees. There was a significant effect of the delay until repair on the angular rotation and linear excursion in all three groups (p less than 0.005 for both). Tensile testing of the bone-tendon complex revealed no significant effect of the delay on the values for ultimate load (p greater than 0.05). There were no significant differences in total concentration of collagen at the sites of repair or in the levels of reducible Schiff-base cross-links (indicators of newly synthesized cross-links) in tendons from the three groups.(ABSTRACT TRUNCATED AT 250 WORDS)

Radial styloidectomy: an anatomical study with special reference to radiocarpal intracapsular ligamentous morphology

This study determines the anatomical relationship of the radiocarpal ligaments to the radial styloid process, and the effect of three specific styloidectomies on the integrity of these ligaments. Thirty fresh cadaveric wrists were dissected. The origins, insertions, and dimensions of each ligament was determined. The thirty wrists were divided randomly into three equal groups and the ten wrists in each group had three types of styloidectomy: short oblique, vertical oblique, and horizontal. The styloid fragments and wrists were then reexamined to determine the integrity of the ligaments. All styloidectomies removed the radial collateral ligament origin. Vertical oblique styloidectomy removed additionally 92% of the radioscaphocapitate and 21% of the radiolunatotriquetral ligament. Horizontal styloidectomy removed 95% of the radioscaphocapitate, and 46% of the radiolunatotriquetral ligament. These findings indicate that the degree of radiocarpal ligament disruption that occurs after styloidectomy may be predicted accurately by correlating the amount of styloid removed, with the consistent ligamentous anatomy of this area.

Cerebral palsy. Management of the upper extremity

Although only a small number of children with cerebral palsy have indications for surgical treatment of dynamic or structural upper-extremity deformities, orthopedic surgery does improve function and appearance of the involved hand, particularly in spastic hemiplegia. For further assessment of the patient after careful physical examination, myoneural nerve blocks and dynamic electromyography are useful. Physical and occupational therapists have an important role as crucial links among parents, patients, and physicians. Surgeons can try to prevent deformity with splints; however, their use in prevention of deformities of the hand has not been validated by scientific studies. Shoulder deformities can be managed with myotomies, tendon transfers, and (if fixed) osteotomies; rarely is arthrodesis used. Elbow flexion and dynamic or fixed deformities greater than 60 degrees are treated by lengthening of the muscles and tendons. Pronation deformities of the forearm are managed by myotomies, lengthenings, and tendon transfers. Wrist flexion deformities can be corrected with tendon lengthenings and transfers. The best results have been obtained with transfer of the flexor carpi ulnaris to the extensor digitorum communis. Finger flexion deformities can be managed satisfactorily with Z-lengthenings of the flexor digitorum superficialis in the forearm; rarely is it necessary to lengthen the flexor digitorum profundus. For adduction deformity of the thumb, division of the proximal or distal insertions of the adductor pollicis and release of the first dorsal interosseus muscle from the first and second metacarpals are preferred.

Excursion of the flexor digitorum profundus tendon: a kinematic study of the human and canine digits

The most common problem following primary flexor tendon repair is the failure of the tendon apparatus to glide, secondary to the formation of adhesions. Early motion following tendon repair has been shown to be effective in reducing adhesions between the tendon and the surrounding sheath. Therefore, it is important to determine the amount of flexor tendon excursion along the digit during joint motion. In this study, the excursion between the flexor digitorum profundus (FDP) tendon and the sheath was examined in both human and canine digits. Based on roentgenographic measurements and joint kinematic analysis, the motion of the bones, the FDP tendon, and the sheath were measured with respect to joint rotations. It was found that the canine flexor tendon apparatus behaved similarly to that of the human for the motions studied. The amount of tendon excursion was very small in regions distal to the joint in motion (approximately 0.1 mm/10 degrees of joint rotation). There was little displacement of the sheath (0.2-0.3 mm), except at the metacarpal joint region during metacarpophalangeal (MCP) joint motion and at the proximal interphalangeal (PIP) joint region during PIP joint motion. Tendon excursion relative to the tendon sheath was the largest in zone II during PIP joint rotation (1.7 mm/10 degrees of joint rotation). These results suggest that PIP joint motion may be most effective in reducing adhesions following tendon repair in zone II.

Carpal tunnel syndrome. Evaluation of a quantitative provocational diagnostic test

A diagnostic test combining the sensitivity of the Semmes-Weinstein monofilament measurement and the specificity of the wrist flexion provocational test has been evaluated in a group of 21 patients (33 hands) with electrodiagnostically verified carpal tunnel syndrome and 30 asymptomatic hands (controls). Semmes-Weinstein monofilament testing consisted of several sensory threshold measurements obtained by the application of force-calibrated Semmes-Weinstein monofilaments to each digit in the hand with the wrist in neutral position. The quantitative provocational diagnostic test employed Semmes-Weinstein measurements obtained with the wrist both in the neutral and flexed positions. The sensitivity (82%) and specificity (86%) of the combined test were calculated. It was more sensitive and specific than the wrist flexion test alone and more specific than the Semmes-Weinstein sensibility test. The combined test is recommended as the most accurate and sensitive quantitative clinical test for median nerve compression evaluated by the authors to date.

Influences of flexor sheath continuity and early motion on tendon healing in dogs

The healing response of flexor tendons treated with either sheath reconstruction or sheath excision, and early passive motion rehabilitation was investigated in a canine model. Flexor sheath repair, sheath excision, and autogenous sheath grafting were compared for biomechanical characteristics, and biochemical and ultrastructural alterations at the repair site at intervals over a 12-week period. No significant differences could be found in tendons treated with either sheath repair or sheath excision by biomechanical, biochemical, or morphologic assessments. Although ultimate load and linear slope values increased significantly in both groups at each interval (p less than 0.05 for each comparison), there were no significant differences in angular rotation of the distal interphalangeal joint over time. Biochemical findings showed high levels of reducible Schiffbase crosslinks through 12 weeks, indicating a repair process undergoing active remodeling. Ultrastructural studies showed active fibrinogenesis and early evidence of longitudinal alignment of collagen fibrils in the extracellular matrix. In the sheath graft group, strength characteristics did not increase over time, and there was a high degree of disorganization of collagen fibril orientation. These findings demonstrate that reconstruction of the tendon sheath, either by suture or autogenous graft, does not improve significantly the biomechanical, biochemical, or morphologic characteristics of repaired tendons treated with early motion rehabilitation.

Carpal tunnel syndrome: morphologic changes after release of the transverse carpal ligament

We describe the morphologic changes that follow division of the transverse carpal ligament in patients with carpal tunnel syndrome. Fifteen hands in 12 patients with carpal tunnel syndrome were studied with magnetic resonance imaging before operation and for 6 weeks after operation. Eight hands were studied at 8 months after operation. Carpal arch width, anterior displacement of the carpal canal contents, and carpal canal volume were measured by use of multiplanar reformation and three-dimensional reconstruction of magnetic resonance images. There was a 24.2 +/- 11.6% increase in carpal canal volume 6 weeks after carpal tunnel release (p less than 0.001). This difference persisted at 8-month follow-up. There was an anterior displacement of carpal canal contents 3.5 +/- 1.9 mm from its original position 6 weeks after operation (p less than 0.001). This palmar displacement persisted at the 8-month follow-up. There was no statistically significant increase in carpal arch width 8 months after carpal tunnel release. We believe that division of the transverse carpal ligament restores median nerve function by increasing the volume of the carpal canal. This volumetric increase results from an anterior displacement of the newly formed transverse carpal ligament and not from a widening of the bony carpal arch.