Rupture of the flexor tendon secondary to osteoarthritis of the pisotriquetral joint: case report.

Attrition ruptures of the flexor tendons in the carpal tunnel are uncommon. A case of rupture of the flexor digitorum profundus tendon to the little finger secondary to osteoarthritis of the pisotriquetral joint is reported. Mechanical attrition against the radial side of the pisiform was thought to be responsible for the rupture.     

Rupture of extensor tendons due to osteoarthritis of the distal radio-ulnar joint

Extensor tendons ruptured in 12 patients as a result of osteoarthritis of the distal radio-ulnar joint. Rupture occurred without warning in ten cases and was sequential in five. Perforation of the dorsal capsule of the distal radio-ulnar joint, allowing contact between the roughened ulnar head and extensor tendons, was present in every case. The capsular performation was demonstrated by arthrography, which may be used to identify patients who are at risk of extensor tendon rupture. Loss of independent extension of the little finger is a valuable clinical sign because rupture of extensor digiti minimi may be masked by a powerful contribution from the extensor tendon of the ring finger.     

Rupture of flexor tendons to the little finger due to bony irregularities in the carpal tunnel

Rupture of a finger flexor tendon occurs most commonly in the patient with rheumatoid arthritis. We have treated two patients who suffered rupture of the flexor tendons to the little finger due to bony irregularities in the carpal tunnel unrelated to rheumatoid disease. Each irregularity was removed and the rough surface covered with a portion of the flexor retinaculum. This resurfacing affords protection against recurrent abrasion and rupture. Tendon function was restored by suturing the ruptured profundus tendon to the adjacent intact profundus tendon of the ring finger. Satisfactory function of the little finger was achieved in both patients. Neither patient has experienced recurrent rupture.     

Rupture of all the flexor tendons in the hand due to malunion of a distal radius fracture

We report the case of a patient in whom the flexor digitorum superficialis and flexor digitorum profundus tendons to the index, middle, ring and little fingers ruptured 6 years following malunion of a distal radius fracture. There was no history of rheumatoid disease. The distal ulna was displaced volarly and perforated the volar wrist capsule. There was a cumulative biological effect from chronic synovitis and mechanical compression due to the ulnar head impinging upon the normal anatomic course of the flexor tendons to the ring and little fingers. We discuss the physiopathology of this rare lesion and postulate that flexor tendon rupture to the index and middle fingers will occur on the volar surface of the radius when there is a malunion with dorsal tilt.     

Rupture of small finger flexor tendons secondary to asymptomatic nonunion of the hamate hook

The incidence of fractures of the hamate hook (hamulus) has been reported to be between 2% and 4% of all carpal fractures. Untreated hamulus nonunion can cause attritional rupture of the ulnar digits' flexor digitorum profundum tendons. Rupture of flexor tendons due to nonunion of the hook of the hamate is an uncommon injury. Most surgeons treat the tendon lesion by a graft, transfer of the superficial flexor of the ring finger, or terminolateral suture of the distal stump of the deep flexor tendon of the little finger to the deep flexor tendon of the ring finger. This article reports a case of a 52-year-old right-handed man who presented with weakness of grip and loss of active flexion of both distal and proximal interphalangeal joints of the right small finger lasting 2 weeks due to grip strength while working. The clinical history and the physical examination were dissonant, and a computed tomography scan revealed a nonunion of the hamulus. Intraoperatively, the nonunion of the hamate hook was identified and the bony ossicle excised. The flexor digitorum profundus and superficialis to the small finger were both ruptured. The flexor digitorum profundus tendon was repaired with a termino-terminal suture. The patient returned to work within 3 months without restriction. Six months postoperatively, the patient had no pain and achieved full active flexion of the small finger.     

Pathologic rupture of flexor tendons due to longstanding Kienb?ck's disease

A 62-year-old man was seen for rupture of the flexor digitorum superficialis and profundus to the index finger. X-ray films showed longstanding Kienb?ck's disease with a completely fragmented lunate bone with fragments lying in front of the anterior lip of the radius. Tendon transfer restored active flexion to the index finger.     

Rupture of flexor tendons after arthrodesis of the basal joint of the thumb.

We report a case of rupture of the flexor tendons to the index finger after arthrodesis of the basal joint of the thumb. The tendons ruptured as a result of the Kirschner wires having penetrated in the carpal tunnel. This unusual complication was treated by tendon graft of the palmaris longus tendon.     

Rupture of the flexor carpi radialis tendon associated with scapho-trapezial osteoarthritis.

A case of rupture of the flexor carpi radialis tendon in association with scapho-trapezial osteoarthritis is reported. The symptoms of pain and swelling contrast with the loss of function which characterizes rupture of other tendons in the hand and wrist.     

The mechanical properties of human flexor tendons in relation to artificial tendons

The continuation of an unacceptable failure rate with tendon repair or grafting procedures, largely due to adhesions, suggested that an artificial flexor tendon could be an attractive alternative. A literature search found no published data of the mechanical properties of fresh human finger flexor tendons, so a study of the strength and extensibility of 153 tendons was carried out. The bone insertion strength of twenty middle finger tendons was also examined. The results showed that an artificial tendon should have a strength of approximately 1500N, and that it should extend 13% at that load, an elongation of 26mm for a tendon 200mm long. The insertion strength was less than a half of the tendon strength. This data will allow an artificial flexor tendon to be designed with sufficient strength and the correct elastic properties to allow its function to integrate reliably with natural tendons in adjacent fingers.     

Gouty involvement of flexor tendons

This article presents three patients suffering from complications related to tophi deposited within the hand and wrist synovium and flexor tendons. One patient had no previous history of gout or acute arthritis, with uricemia within normal values upon admission. The pathophysiology and treatment of gout in these special circumstances are discussed.     

Tissue engineering of flexor tendons

Despite technical advances in suture methods and rehabilitation protocols, challenges remain in the field of flexor tendon repair. This article reviews the state-of-the-art research in the tissue engineering of flexor tendons. These early published data will hopefully lay the foundation for molecular methods and materials that can be used to reconstruct tendons to restore normal form and function in the hand.     

Biomechanics of the flexor tendons

This article examines basic tendon biomechanics, the anatomy and mechanics of digital flexor tendons, and the digital flexor pulley system. It also explores the various models that have tried to simulate the motion of the flexor tendons and several testing modalities that have been used. Finally, clinical applications are considered, including the biomechanics of flexor tendon repairs and tendon transfers. As we reach limits in the care of flexor tendon injuries, research into molecular, biochemical, and micromechanical methods of tendon repair will become the forefront of future investigation.     

Closed rupture of the flexor tendons of the thumb and index due to severe scaphotrapezoidal arthritis

We report a case of severe scaphotrapezoidal osteoarthritis with closed rupture of multiple flexor tendons. The thumb was treated with a tenodesis with the remaining flexor and the deep flexor of the index was reconstructed with a short cable graft, harvested from the superficial flexor.     

Delayed sequential ruptures of the index and thumb flexor tendons due to an occult scaphoid nonunion

A case of sequential spontaneous loss of flexion in the thumb and index finger over a 10 year period is reported. Previously unrecognized carpal collapse as a consequence of a longstanding scaphoid nonunion was identified as the cause. Fusion of the interphalangeal joint of the thumb and suture of the index profundus tendon to the middle profundus tendon resulted in a good outcome.     

Quantification of regional blood flow to canine flexor tendons

Although the blood supply and the microcirculation of flexor tendons have been studied and defined extensively using qualitative methods, the quantitative assessment of blood flow has been lacking because of the limitations of the available experimental techniques. We studied the regional blood supply to the flexor tendons of dogs by the technique of radionuclide-labeled microspheres. Seven adult mongrel dogs were used. Microsphere injection and tissue-counting techniques previously used for other tissues were applied. Samples of proximal, isthmus, and distal portions of the profundus and superficialis flexor tendons were harvested from each digital unit of available limbs from each dog. Mean (+/- SE) flows (ml/100 g dry tissue/min) were proximal profundus 1.78 +/- 0.60 and superficialis 7.10 +/- 1.50. The differences were significant (p less than 0.01). The study suggests that regional variation in blood flow to canine digital flexor tendons exists, so that a single value for blood flow to these tendons is not relevant. Furthermore, the study supports the concept of dual (vascular and synovial) nutrition to the digital flexor tendons in dogs. These observations may have implications regarding tendon repair techniques.