Interphalangeal Hyperextension Research Articles

Spiral Oblique Retinacular Ligament Procedure Using Flexor Digitorum Profundus Hemi-Tendon Transfer: Anatomical Basis and Clinical Application

The spiral oblique retinacular ligament (SORL) procedure acts as a dynamic tenodesis to restore distal interphalangeal joint (DIP) extension and restrain proximal interphalangeal hyperextension. Despite the ingenious technique based on the oblique retinacular ligament anatomy, obtaining strong internal fixation remains an issue during the SORL procedure. We present a modified technique using the flexor digitorum profundus (FDP) hemi-tendon transfer. We dissected 5 fresh cadaveric specimens to evaluate morphometric parameters of the SORL procedure using the hemi-FDP. The volar groove of the FDP tendon was identified in zone I of the flexor sheath and the tendon was divided into radial and ulnar bundles. The selected hemi-tendon was divided at the proximal edge of the A1 pulley and a SORL procedure was performed through a transosseous tunnel in the distal phalanx. This technique was used in 3 patients with swan neck deformity. The optimal distance between the DIP joint and the anterior drill hole of the transosseous tunnel was 7.6 mm (range, 6.8-8.5 mm). The relative loss of length of the tendon owing to the SORL path was 25.8 mm (range, 19.6-29.9 mm). In the clinical cases, the procedure improved DIP joint extension lag and prevented proximal interphalangeal joint hyperextension. Preserving one-half of the FDP allowed complete flexion of the DIP joint. The procedure is technically feasible. Its main advantages are that a distal suture is not required and that the substantial length of the tendon allows sturdy proximal internal fixation. Therapeutic V.

Kinematic evaluation of the finger’s interphalangeal joints coupling mechanism—variability, flexion–extension differences, triggers, locking swanneck deformities, anthropometric correlations

The human finger contains tendon/ligament mechanisms essential for proper control. One mechanism couples the movements of the interphalangeal joints when the (unloaded) finger is flexed with active deep flexor. This study’s aim was to accurately determine in a large finger sample the kinematics and variability of the coupled interphalangeal joint motions, for potential clinical and finger model validation applications. The data could also be applied to humanoid robotic hands. Sixty-eight fingers were measured in seventeen hands in nine subjects. Fingers exhibited great joint mobility variability, with passive proximal interphalangeal hyperextension ranging from zero to almost fifty degrees. Increased measurement accuracy was obtained by using marker frames to amplify finger segment motions. Gravitational forces on the marker frames were not found to invalidate measurements. The recorded interphalangeal joint trajectories were highly consistent, demonstrating the underlying coupling mechanism. The increased accuracy and large sample size allowed for evaluation of detailed trajectory variability, systematic differences between flexion and extension trajectories, and three trigger types, distinct from flexor tendon triggers, involving initial flexion deficits in either proximal or distal interphalangeal joint. The experimental methods, data and analysis should advance insight into normal and pathological finger biomechanics (e.g., swanneck deformities), and could help improve clinical differential diagnostics of trigger finger causes. The marker frame measuring method may be useful to quantify interphalangeal joints trajectories in surgical/rehabilitative outcome studies. The data as a whole provide the most comprehensive collection of interphalangeal joint trajectories for clinical reference and model validation known to us to date.

Repair of Chronic Mallet Finger Deformity Using Mitek Micro Arc Bone Anchor

Surgical correction of chronic mallet finger caused by terminal tendon disruption was carried out in 22 patients. The distal stump of the tendon was fixed to the base of the distal phalanx with a Mitek micro arc bone anchor. In all patients the mallet finger deformity was corrected. There were 15 patients with excellent results, 5 with good results, and 2 with fair results. None of the patients had a poor result. No further treatment was needed. The Mitek micro arc bone anchor system is a reliable alternative for the treatment of chronic mallet finger deformity without proximal interphalangeal hyperextension.

Flexor tendon lacerations in zone V

Twenty-three patients with zone V flexor tendon lacerations rehabilitated by the Kleinert protocol were studied at an average of 46 months after trauma. Hand function was subjectively normal in only eight. Of fourteen patients who were employed at the time of injury, eight returned to their original occupations. Eight others were working at other jobs, and we considered six more capable of employment. Only one had a poor functional result that precluded occupational use of the hand. Pinch/grip strengths recovered to 85% 79% of the uninvolved side. Independent flexor digitorum superficialis/flexor digitorum profundus action was present in only seven patients. Sixteen regained full digital flexion. Extension loss averaged 25% at the wrist and 10% in each digit. As assessed by static two-point discrimination, sensibility was poor after associated median and ulnar nerve transections; this did not preclude good objective functional results. Complications included two tendon ruptures, proximal interphalangeal hyperextension in the presence of an unrepaired flexor digitorum superficialis, and limited motion in two patients after poor compliance in therapy. Tenolysis was needed in 4 of the 23. We now use a modified Duran technique for noncompliant patients and in those who are unable to extend their PIP joints because of weak intrinsic muscles.

The spiral oblique retinacular ligament (SORL)

A procedure is described for reconstruction of the oblique retinacular ligament using a small tendon graft in a spiral fashion to act as a dynamic tenodesis to restore distal interphalangeal extension and to restrain proximal interphalangeal hyperextension. The method has been uniformly successful in the treatment of post-traumatic "swan-neck" or "mallet" deformity. Although the concept is simple, the procedure demands thorough understanding of digital anatomy for successful completion.

The hallux and rheumatiod arthritis.

The purpose of this report is to consider involvement of the great toe by rheumatoid arthritis, defining significant deformities, describing clinical patterns and discussing the pathomechanics of these findings, in what is an ongoing disease. 200 consecutive patients admitted to hospital with classical or definite rheumatoid arthritis were screened for pain or deformity of the great toe. Feet that had undergone previous surgery or had other underlying pathology were excluded from the series. 194 feef were found to have halluceal involvement. Although hallux valgus was the commonest deformity it was found in combination with other significant deformities in many cases. Hallux rigidus was an important lesion in this series as was interphalangeal hyperextension. Other important lesions encountered were metatarsus primus varus and medial rotation of the toe; their relationship to hallux valgus is discussed.