The Primary Sauve–Kapandji Procedure—For Treatment of Comminuted Distal Radius and Ulnar Fractures

We have performed primary Sauve–Kapandji procedures on four patients with severe open comminuted fractures of both the distal radius and ulna. The fragmented distal ulna was fixed to the sigmoid notch in order to stabilize the ulnar side of the carpus, and a proximal pseudoarthrosis was maintained for forearm rotation. All the distal radial fractures united without major complications. The mean wrist flexion/extension arc was 76°, the mean pronation/supination arc was 135°, and grip strength was 64% of the contralateral side. All patients returned to their work or daily activities within short time period without any additional surgical treatment, except for removal of implants in three patients. The primary Sauve–Kapandji procedure is effective for the reconstruction of severely combined distal radius and ulnar fractures.

DIFFERENCES IN RADIOGRAPHIC FINDINGS BETWEEN SCAPHOID FRACTURE PATTERNS

Scaphoid fracture patterns can be divided into volar and dorsal type using three-dimensional computed tomography. Ninety-nine patients underwent this examination plus radiography to determine how often fracture pattern was identifiable by radiography including proximal fragment ratio (PFR) measurement. Oblique radiographs obtained at 45° of pronation demonstrated a volar displacement in 28 of 37 volar type fractures in three-dimensional computed tomography (76%), while as oblique view with 45° of supination could identify the dorsal type in ten of 18 (56%). PFR showed a significant difference, with means of 0.59 for volar type and 0.43 for dorsal type. Using oblique views in the two rotational directions together with the PFR, the two fracture patterns could be differentiated in 35 of 43 fractures (81%). No differences were evident between the two fracture patterns with respect to prevalence of dorsal intercalated segment instability deformity.

Results of ulnar shortening osteotomy for ulnocarpal impaction syndrome in wrists with neutral or negative ulnar variance

Ulnocarpal impaction syndrome was diagnosed in six wrists of five patients with neutral or negative ulnar variance. All underwent ulnar shortening with satisfactory results. The average grip strength increased from 53% to 78% and the range of flexion-extension increased from 82% to 93%, the mean Cooney's score improved from 25 to 83. These cases show that ulnocarpal impaction syndrome can occur in wrists with zero or negative ulnar variance, and that ulnar shortening is an effective treatment for such wrists.

Triphalangeal thumb without associated abnormalities: clinical characteristics and surgical outcomes

Thirty-four triphalangeal thumbs of 23 patients, who had no associated anomaly in their ipsilateral hand, were reviewed to clarify the characteristics of an isolated triphalangeal thumb and its surgical outcome. There were 13 type 1 thumbs, 21 type 2 thumbs, and no type 3 thumbs. The existence of an accessory phalanx caused ulnar bending at the interphalangeal joint. Thirteen type 1 thumbs were operated on by excising an accessory phalanx. Corrective osteotomy at the epiphysis was performed on four type 2 thumbs, and partial excision of the epiphysis was performed on 11 type 2 thumbs. At follow-up examination, the average interphalangeal joint motion was 54 degrees in type 1 thumbs and 53 degrees in type 2 thumbs. More than 10 degrees of lateral bending remained in one type 1 thumb and six type 2 thumbs. Good results were observed when an early excision of the accessory phalanx with a securing collateral ligament was performed on type 1 thumbs. For type 2 thumbs, partial excision of the epiphysis provided relatively better correction than osteotomy. For good adaptation of interphalangeal joints, surgery should be performed when the patient is between the ages of 1 and 2, when the epiphysis is visible on x-rays.

Diagnostic imaging for fracture of the hook of the hamate

We experienced 16 patients with a fracture of the hook of the hamate. The routine posteroanterior view raised the suspicion of fracture in four of 13 patients (31%), the carpal tunnel view showed the actual fractures in six of 14 patients (43%), and the supine oblique radiographic view of the wrist showed fractures in eight of ten patients (80%). Computed tomography corroborated the fracture in all eight patients (100%). Computerized tomography proved most useful for accurate diagnosis of fracture of the hook of the hamate.

Theoretical stress analysis in wrist joint--neutral position and functional position

A three-dimensional rigid body spring model (3D-RBSM) was used to analyse force distribution through the wrist joint. In the neutral position, 48% of the force was transmitted through the radioscaphoid fossa, 40% through the radiolunate fossa, and 12% through the triangular fibrocartilage complex. In the functional position, the wrist joint was slightly extended, resulting in significantly increased force through the lunate (53%). The lunate appears to bear more load than has been reported previously.

Distraction lengthening of the forearm for congenital and developmental problems

Thirty-five callus distractions of the forearm were carried out in 23 patients, who were divided into two groups according to the cause of the shortening. Eleven cases in group A had congenital dysplasia, and the 12 cases in group B had growth disturbances from tumours or infection. The mean amount of lengthening was 27 mm in group A and 25 mm in group B. The mean percentage increase in length was 35% and 17%, respectively. The mean duration of fixation was 159 days and 127 days, respectively. The Healing Index had a positive correlation with the age at surgery in group A, but not in group B. The main complication was callus deformity after the removal of a fixator, which was especially frequent in group A. To avoid complications, the aetiology of shortening and the age of the patient should be considered when deciding the surgical protocol.

Proximal row carpectomy versus limited wrist arthrodesis for advanced Kienböck's disease

The outcomes in 20 patients with advanced Kienböck's disease treated by proximal row carpectomy (seven patients) or limited wrist arthrodesis (13 patients) were reviewed retrospectively. Postoperatively, the results were more satisfactory in terms of wrist pain, the range of wrist flexion-extension, and grip strength following limited wrist arthrodesis than after proximal row carpectomy, although the differences were not statistically significant. We recommend scaphotrapeziotrapezoid arthrodesis in selected patients with advanced Kienböck's disease who have a fragmented lunate.

A syndrome of digital fibromas, facial pigmentary dysplasia, and metacarpal and metatarsal disorganization

We report on a girl with fibrous tumors involving hands and feet associated with unusual brachydactyly and facial abnormalities with pigmentary skin lesions. The multiple, infiltrative fibrous tumors clinically resembled recurring digital fibromata (RDF) of infancy, but eosinophilic cytoplasmic inclusion bodies pathognomonic for RDF were not demonstrated in her tumor cells. Skeletal alterations of the hands and feet comprised brachymesophalangy with cone-shaped epiphyses and variable shortening and deformity of the metacarpals and metatarsals. Facial abnormalities included upward slant of palpebral fissures, primary telecanthus with epicanthal folds, and a depressed nasal tip, along with a small fibrous tumor on the left eyelid. The patient also had patchy, brownish discolorations of the face. The clinical, radiological, and histological constellation in the patient may represent a hitherto undescribed hamartomatous syndrome.

Surgical treatment of congenital metacarpal synostosis of the ring and little fingers

Fifteen hands with congenital metacarpal fusions were treated operatively by osteotomy combined either with the use of a silicone block or a distraction device. The aim of the silicone block was to separate the fused metacarpals, but it was buried in the metacarpals at follow-up, with recurrence of fusion. By the distraction technique, 13 mm of lengthening was obtained. The average length of the little metacarpal was 88% of that of the long finger metacarpal. Both methods were effective in correcting the abduction deformity of the little finger by a mean of 34 degrees, and increasing the range of motion of the metacarpophalangeal joint to 28 degrees of active flexion. Although the distraction method took longer than the silicone block method, the final appearance of the hand was better.

Ulnar styloid malunion with dislocation of the distal radioulnar joint

Four patients with dorsal dislocation of the distal radioulnar joint and ulnar styloid malunion had corrective osteotomy of the ulnar styloid. Dislocation of the distal radioulnar joint was reduced in three of four patients. Subluxation persisted in the remaining patient. Wrist function improved in all patients. These results support the contention that a displaced ulnar styloid fracture with distal radioulnar joint dislocation should be reduced and internally fixed. Corrective osteotomy is recommended for malunion of the ulnar styloid associated with dislocation of the distal radioulnar joint.

The ulnocarpal stress test in the diagnosis of ulnar-sided wrist pain

Forty-five patients with persistent ulnar-sided wrist pain and a positive ulnocarpal stress test were investigated by X-ray, arthrography, 99mTechnetium bone scanning, magnetic resonance imaging and wrist arthroscopy. Ulnar wrist pathology was positively identified in nine of 45 patients by X-ray, 18 of 37 by arthrography, 19 of 27 by bone scan, four of 33 by MRI, and in all 45 patients by arthroscopy. The final diagnosis was ulnocarpal abutment syndrome in 28 patients, traumatic triangular fibrocartilage (TFC) tear in six, lunotriquetral (LT) ligament tear in five, TFC and LT ligament tear in one, wrist arthritis in four and cartilaginous free body in one. The ulnocarpal stress test is a useful provocative test, and a positive test suggests the presence of ulnar-sided wrist pathology. The test is sufficiently sensitive to warrant further investigation by arthroscopy.

Avulsion fracture of the metacarpophalangeal joint of the finger

Six patients with avulsion fractures of the metacarpophalangeal joints of the fingers are reported. Operation was performed in all cases. Judging from the operative findings, the radiological assessment of fragment shape is helpful in treatment. Surgery is recommended when the fragment is triangular or rectangular in shape because the fracture involves the articular surface. Conservative treatment is effective if the fragment is round because the articular surface of the joint is not involved in this type of fracture. The avulsed fragment often overlaps the metacarpal head and a collateral ligament injury is likely to be misdiagnosed. It is important to suspect this injury and assess the shape of the whole fragment for a good functional result.

Duplicated thumb bifurcation at the metacarpophalangeal joint level: factors affecting surgical outcome

In order that the factors causing poor surgical outcome might be clarified, 175 duplicated thumbs bifurcating at the metacarpophalangeal joint level were analyzed. Cases were further divided into types A-D, based upon the details of the bifurcation form; that is, based on the connection of the radial digit to the ulnar components by either cartilage, joint, or fibrous tissue. The incidence of each type was 16% for type A (wide cartilaginous connection between phalanges), 68% for type B (2 separate phalanges), 6% for type C (cartilaginous connection to metacarpal), and 10% for type D (fibrous connection to joint capsule). Triphalangeal types and the relative size of the excised digit were determined by the preoperative radiograph. One hundred six cases were available for evaluation with a minimum of 3 years' follow-up. Good results were obtained in 50% of types A and C and in 80% of types B and D. Three phalanges in the preserve digits were observed in 10 cases and surgery on all but 1 resulted in a fair outcome. In cases where the size of the excised digit was more than 75% of the preserved digit, the results were fair or pool in 93%. The presence of subdivisions of types A and C, of 3 phalanges in the preserved digit, and of a relatively bigger excised digit were factors causing poor results, despite intensive reconstructive surgery.

Criteria for diagnosing distal radioulnar joint subluxation by computed tomography

Bilateral wrist computed tomography (CT) was performed in 30 patients with suspected unilateral distal radioulnar joint (DRUJ) subluxation to evaluate dynamic DRUJ CT scanning with a straight elbow. Five CT criteria for diagnosing dorsovolar subluxation were examined. Maximum active supination and pronation on a conventional scanning table yielded satisfactory rotation (mean +/- SD, 119 degrees +/- 29 degrees) at the DRUJ, thus permitting a dynamic diagnosis of DRUJ subluxation. The radioulnar line method and the congruity method frequently yielded false positive results compared with bilateral diagnosis and were unreliable. Modifications of these two methods achieved sensitivity and specificity comparable to the epicenter method. We recommended the modified radioulnar line method for diagnosing dorsovolar subluxation using unilateral CT because of its excellent sensitivity and specificity combined with ease of technique.

Distal radioulnar joint subluxation and dislocation diagnosed by standard roentgenography

The use of standard lateral roentgenography for diagnosing distal radioulnar joint (DRUJ) subluxation and dislocation was investigated. Using a wrist support, bilateral standard lateral roentgenograms of the wrist were obtained in 42 patients with normal wrists and in 56 patients with a unilateral wrist injury. In normal wrists the difference between the radioulnar distance in the right and the left wrist did not exceed 4 mm when the difference in the pisoscaphoid distance was less than 3 mm. Of the 36 patients with wrist injury whose difference in pisoscaphoid distance was less than 3 mm, 15 had a radioulnar distance of 5 mm or more, and computed tomography (CT) confirmed DRUJ dislocation in 14. Concordance between lateral roentgenograms and CT was present in 33 of 36 patients (92%). These results demonstrate the value of a standardized technique for bilateral lateral roentgenography in diagnosing DRUJ subluxation and dislocation.

The position of symbrachydactyly in the classification of congenital hand anomalies

The clinical features of 53 cases of intercalated hypoplasia and 113 cases of distal aplasia are reviewed and compared with each other and with 129 cases of syndactyly. Tri-, di- and mono-phalangeal symbrachydactyly, and adactyly with nubbin digits are consecutive anomalies. Transverse deficiency may result if the mesenchyme is damaged severely, and if damage is mild and formation has continued, intercalated transverse deficiency may occur. Webbing in symbrachydactyly may result from failure of the apical ectodermal ridge under the influence of damaged mesenchyme.

Ulnar ray deficiency. A report of a family

We report three cases of ulnar ray deficiency in one family. The father had a left ring finger deficit, and a hypoplastic little finger was amputated at childhood. His first baby had a deep cleft between the ring and little finger in the right hand, and his second baby had complete absence of the left ulna, only one metacarpal, and two digits were present on the hand. All three cases were unilaterally involved and they had no other skeletal abnormalities.

Scaphoid fracture as a "puncher's fracture"

We investigated 18 scaphoid fractures induced by punching. The wrist position while punching was neutral to slight palmar flexion. We postulated that the mechanism of the fracture was caused by the concentration of the external force to the second metacarpus. The forces are then dispersed to the trapezium and trapezoid, which produces shear stress at the waist of the scaphoid. In spite of the differences in mechanism, the location of the fracture was similar to fractured scaphoids caused by wrist extension injuries. Regardless of the wrist positions, the carpal scaphoid is most vulnerable to fracture due to its characteristic morphology.

The aetiological significance of work-load in the development of osteoarthritis of the distal interphalangeal joint

The incidence of Heberden's nodes was determined in three groups of Japanese women with different occupations to investigate the role of work-load in their pathogenesis. School cooks (n = 260), each of whom prepared 150 to 450 lunches daily, pre-school cooks (n = 222), each of whom prepared 30 to 80 lunches daily, and municipal employees (n = 298) underwent physical examination and X-ray of the hand if pathology was present. The incidence of Heberden's nodes and X-ray incidence of osteoarthritis was 19.2% and 13.5%, 8.6% and 5.4%, 5.9% and 2.0% among school cooks, pre-school cooks and municipal workers, respectively. The incidence of Heberden's nodes and osteoarthritis was significantly higher among school cooks. These findings support the concept that work-load is an aetiological factor in the pathogenesis of Heberden's nodes and also support Radin's hypothesis that women's daily work pattern explains the increased incidence of DIP joint osteoarthritis in women.

Biomechanical analysis of radial wedge osteotomy for the treatment of Kienböck's disease

Biomechanical analysis of force transmission through the lunate was performed with the use of a two-dimensional mathematical model to evaluate the usefulness of radial wedge osteotomy, a procedure that decreases radial inclination, in the treatment of Kienböck's disease. The forces acting on the carpal bones were compared before and after radial wedge osteotomy in 29 patients with Kienböck's disease. The average osteotomy angle was 9.6 degrees. The total force through the lunocapitate joint at the midcarpal level was decreased by 23%, while the total force through the radiolunate and ulnolunate joints at the radioulnocarpal level was decreased by 10% and 36%, respectively. These changes correlated directly with the osteotomy angle and demonstrate decompression of the lunate by radial wedge osteotomy.

Changes in carpal alignment following radial osteotomy for Kienböck's disease

Changes in carpal alignment following radial osteotomy were studied in 30 patients with Kienböck's disease. The carpal height ratio and carpal-ulnar distance ratio were significantly less in wrists with Kienböck's disease than unaffected wrists. This observation implies proximal-ulnar translation of the capitate. In addition, the lunate-covering ratio increased significantly, reflecting radial translation of the lunate. Radial osteotomy corrected ulnar translation of the capitate and increased the radial translation of the lunate, thus increasing the lunate-covering ratio. The increased lunate-covering ratio is believed to increase the area of distribution of the axial load through the lunate by increasing the contact area with the radius. The satisfactory clinical outcome of radial osteotomy is believed to be due to this effect on carpal alignment.

Scaphoid non-union: factors affecting the functional outcome of open reduction and wedge grafting with Herbert screw fixation

50 patients with scaphoid non-union were treated by open reduction, anterior wedge bone grafting and internal fixation using the Herbert screw. Intra-operative image intensifier control enabled us to insert the screw into the scaphoid accurately. An excellent or good functional outcome was less likely when more than 5 years had elapsed since injury, the non-union was in the proximal third, when sclerosis of the proximal fragment was present, and when reduction of carpal and scaphoid deformity was unsatisfactory. These four factors are believed to be the primary determinants affecting the functional results of the surgical treatment of scaphoid non-union, even when bony union is achieved.

Stability and constraint of the proximal interphalangeal joint

The kinematics of the intact proximal interphalangeal joint of 12 fresh cadaver index fingers were measured by means of an electromagnetic tracking system. The specimens were then randomly divided into two groups for ligament sectioning in two different sequences and for testing under lateral stress. Lateral stress of the intact proximal interphalangeal joints produced an average of 5 degrees of adduction and 9 degrees of supination motion throughout the arc of flexion/extension. Maximum lateral angulation was 15 degrees under 1 kg of force (30 N cm) applied at the distal end of the middle phalanx. Joint angulation increased to 20 degrees after total sectioning of the collateral ligament. Joint laxity was greatly reduced in full extension, in full flexion, and when the muscles were loaded. The proximal interphalangeal joint remained stable when one half of the collateral ligament was left intact. The results indicate that lateral stability of the proximal interphalangeal joint is provided primarily by the collateral ligament. When the lateral stress test is normal in proximal interphalangeal joint extension, an additional test in 20 to 30 degrees of flexion should be considered to avoid a false-negative result. Angulation greater than 20 degrees is abnormal and indicates a loss of collateral ligament integrity.

Premature closure of the distal radial physis

Two cases of fracture of the radius treated by pinning resulted in severe wrist joint deformity due to premature closure of the epiphysial growth plate. Inappropriate pinning through the physis damaged the growth plate in both cases. They were treated by bone bridge resection with free fat interposition. The bone bar resection was effective in correcting the wrist joint deformity, and bone growth was expected without bone grafting.

Excursion of prime wrist tendons

To allow continuous and simultaneous measurements of tendon excursion and joint rotation angles, we developed a system using an electric potentiometer and an electromagnetic tracking device. Instantaneous moment arms of each tendon could then be calculated on the basis of the slope of the curve between tendon excursion and joint angular displacement. Five prime wrist motor tendons were studied on freshly frozen cadavers. Calculated tendon moment arms were found to be consistent throughout a full range of flexion-extension wrist motion and radioulnar deviation and corresponded closely to the anatomic location and orientation of the tendons. The flexor carpi ulnaris tendon provided the largest moment contribution to the wrist joint. Forearm rotation did not affect the function of the wrist tendon except for the extensor carpi ulnaris. During flexion-extension motion, the excursion of the extensor carpi ulnaris decreased significantly from 10 to 4 mm, with the forearm in neutral and pronated positions. During radioulnar deviation, the excursion of the extensor carpi ulnaris increased from 14 to 17 mm with the forearm in supinated and pronated positions.

[Posterolateral rotatory instability of the elbow--a case report and anatomical study of the lateral collateral ligament]

A 20-year-old woman was referred to our clinic complaining of recurrent subluxation of her right elbow. A posterolateral rotatory instability test revealed that she had insufficiency of the lateral collateral ligament. She was surgically treated; the ligament was reconstructed by using the palmaris longus tendon. A year after operation, she had no pain in her elbow, and regained full range of elbow motion. The function of the lateral collateral ligament is often overlooked. We, therefore, dissected 24 elbow joints and studied anatomically in order to confirm the origin and insertion of the lateral collateral ligament. The ligament originates from the lateral epicondyle, and runs distally in fan shape. It further inserts partly to the annular ligament and partly to the supinator crest. After complete sectioning of the ligament, the forearm was fixed in supination, then flexed with valgus moment. This maneuver elicited subluxation of the radio-humeral joint, which was similar to what we observed in the clinical case. From these observations, we have concluded that the ligament is important for stability of elbow joint as well as the medial collateral ligament.

Combined shear fractures of the trochlea and capitellum associated with anterior fracture-dislocation of the elbow

This article presents two unusual cases of combined shear fractures of the trochlea and capitellum associated with anterior fracture-dislocation of the elbow. The mechanism of injury was thought to be a fall on the dorsum of a partially flexed forearm, in which the trochlea and capitellum are displaced by the fractured olecranon and the radial head.

Comparative flexor tendon excursion after passive mobilization: an in vitro study

Two experimental studies were conducted to investigate flexor tendon excursions. In the first study, tendon excursions due to passive joint motion in various loading condition were evaluated. In the second study, the efficacy of a new technique that used synergistic wrist motion (S-splint) was compared with the traditional dorsal splinting methods: the Kleinert splint (K-splint) and the Brooke Army Hospital/Walter Reed modified Kleinert splint with a palmar bar (P-splint). The results of these studies question the anticipated tendon excursion associated with postoperative splinting. They demonstrated that the measured tendon excursion under a condition of low tendon tension was almost half that of theoretically predicted values. In zone II, the magnitude of excursion introduced by the three mobilization methods were in descending order: S-splint, P-splint, K-splint (p less than 0.05). Differential tendon excursion between the flexor digitorum profundus and the flexor digitorum superficialis had a mean value of 3 mm and was not significantly different among the three methods. Passive proximal interphalangeal joint motion was the most effective means of providing increased amplitude of tendon gliding in zone II. Passive distal interphalangeal joint motion did not increase excursion in zone II as much as had been predicted.

The Sauvé-Kapandji procedure for chronic dislocation of the distal radio-ulnar joint with destruction of the articular surface

The Sauvé-Kapandji procedure has been performed in 15 non-rheumatoid patients with chronic distal radio-ulnar joint dislocation accompanied by joint damage or deformity. The clinical results were favourable; wrist pain improved in all patients, wrist flexion-extension was increased by more than 10 degrees in nine patients, grip strength of at least 80% of the contralateral wrist was achieved in 11 patients, and forearm rotation was more than 150 degrees in 12 patients. However, X-ray examination revealed an unstable proximal ulnar stump and radio-ulnar convergence in all patients similar to that associated with the Darrach procedure. Although the Sauvé-Kapandji procedure can preserve ulnar support of the wrist and is believed to yield more satisfactory results than the Darrach procedure, its extensive use is not recommended for non-rheumatoid distal radio-ulnar joint disorders, but it is recommended for chronic distal radio-ulnar joint dislocation with articular injury or deformity.

Force distribution across wrist joint: application of pressure-sensitive conductive rubber

A new pressure-sensitive conductive rubber sensor was used for investigation of the pressure distribution through the radio-ulno-carpal joint. Twelve of these transducers were placed in the radio-ulno-carpal joint. Pressure was measured in seven different wrist positions under loads incrementally increasing from 0 to 12 kg. Half of the sensors showed less than 0.5 MPa, even at maximum load, while a high-pressure area was located palmary in each fossa. The peak pressure measured in the wrist neutral position was 2.4 MPa on the scaphoid fossa, 1.5 MPa on the lunate fossa, and 1.1 MPa on the triangular fibrocartilage with a 10 kg load. The peak pressure ratio between the scaphoid and the lunate was 1.7 in the neutral wrist position. This increased in radial deviation to 2.9 and decreased in ulnar deviation to 0.8. The force-transmission ratio was 50% through the scaphoid fossa, 35% through the lunate fossa, and 15% through the triangular fibrocartilage in the neutral position. The advantage of this sensor is that it is thin and flexible and provides reliable reproducible quasi-instantaneous measurements.

The relationship between wrist position, grasp size, and grip strength

In the first part of this study, the position assumed by a normal wrist during unconstrained maximal grip and the relationship between wrist position and grip strength were investigated in 20 healthy subjects. Grip strength and wrist position were recorded in the self-selected position and then again while the subjects voluntarily deviated the wrist randomly into flexion, extension, or radial or ulnar deviation of 10 to 15 degrees. The self-selected position was 35 degrees of extension and 7 degrees of ulnar deviation. Grip strength was significantly less in any position of deviation from this self-selected position, even after accounting for fatigue. With the wrist in only 15 degrees of extension or in neutral radio-ulnar deviation, grip strength was reduced to two thirds to three fourths of normal. Sex did not affect wrist position. The dominant wrists were within 5 degrees of the nondominant ones but were relatively less extended and in more ulnar deviation. Grip strength is significantly reduced when wrist position deviates from this self-selected optimum position. In the second part of the study, the effect of grasp size on this self-selected position was studied in 21 subjects. The degree of wrist extension was inversely and linearly related to how large a setting on the Jamar dynamometer was used. This was true regardless of hand size, although the effect was more significant for smaller hands. Radial and ulnar deviations were not affected by handle position. A minimum of 25 degrees of wrist extension was required for optimum grip strength.(ABSTRACT TRUNCATED AT 250 WORDS)

The cubital tunnel and ulnar neuropathy

The anatomy of the cubital tunnel and its relationship to ulnar nerve compression is not well documented. In 27 cadaver elbows the proximal edge of the roof of the cubital tunnel was formed by a fibrous band that we call the cubital tunnel retinaculum (CTR). The band is about 4 mm wide, extending from the medial epicondyle to the olecranon, and perpendicular to the flexor carpi ulnaris aponeurosis. Variations in the CTR were classified into four types. In type 0 (n = 1) the CTR was absent. In type Ia (n = 17), the retinaculum was lax in extension and taut in full flexion. In type Ib (n = 6) it was tight in positions short of full flexion (90 degrees to 120 degrees). In type II (n = 3) it was replaced by a muscle, the anconeus epitrochlearis. The CTR appears to be a remnant of the anconeus epitrochlearis muscle and its function is to hold the ulnar nerve in position. Variations in the anatomy of the CTR may explain certain types of ulnar neuropathy. Its absence (type 0 CTR) permits ulnar nerve displacement. Type Ia is normal and does not cause ulnar neuropathy. Type Ib can cause dynamic nerve compression with elbow flexion. Type II may be associated with static compression due to the bulk of the anconeus epitrochlearis muscle.

Analysis of scaphoid fracture displacement by three-dimensional computed tomography

Scaphoid fracture displacement was studied in twenty-five patients using three-dimensional computed tomography. Fracture displacement was more readily detected and distinct in three-dimensional computed tomography images than in plain radiography. Two different types of offset of the distal fragment with respect to the proximal fragment are described on three dimensional computed tomography; volar type and dorsal type. In the volar type, the distal fragment overhung in the volar direction relative to the proximal fragment and was frequently accompanied by humpback deformity and axial rotation. In the dorsal type, the distal fragment slipped dorsal on the proximal fragment and was commonly accompanied by humpback deformity. The volar type had a transverse or vertical fracture line on both the volar and dorsal surfaces of the scaphoid, while the dorsal type had a horizontal fracture line. The volar type was frequently found when the fracture was distal, whereas the dorsal type was noted more frequently for proximally located fracture.

A kinematic study of luno-triquetral dissociations

An analysis of carpal motion after sectioning the ligamentous support of the luno-triquetral joints was done by use of stereoradiographic methods. The ligaments were sectioned in two stages. In stage I, a complete sectioning of both the dorsal and palmar luno-triquetral ligaments and the interosseous membrane was done. Stage II consisted of further sectioning of both the dorsal radio-triquetral and dorsal scapho-triquetral ligaments. After both stage I and stage II ligament sectioning, all of the intercarpal joints exhibited altered kinematics. The changes were especially marked at the luno-triquetral joint where motion was increased in all planes of wrist motion. The essential lesion in producing a static palmar flexed intercalated segment instability was division of the dorsal radio-triquetral and dorsal scapho-triquetral ligaments in association with the luno-triquetral ligaments and interosseous membrane sectioning.

Congenital hand anomalies in Japan: a family study

During the 20-year period from 1968 to 1987, 1024 patients with congenital anomalies of the hand from 1000 Japanese families were examined in our clinic. Of these patients, 204 had relatives with limb anomalies. While postaxial polydactyly showed a 33% level of familial recurrence, symphalangism and Kirner's syndrome showed about 23% recurrence, syndactyly 18%, radioulnar synostosis 9%, radial ray deficiency 8%, cleft hand 7%, and duplicated thumb 5%. None of the relatives had ulnar deficiency or symbrachydactyly.

Effect on force transmission across the carpus in procedures used to treat Kienböck's disease

A simplified two-dimensional articulating force analysis (rigid body spring model) examined how different surgical procedures used for treating Kienböck's disease modify the force distribution across the carpus. A two-dimensional model of a carpus was loaded through the metacarpals by forces of up to 143 Newtons. The resulting intercarpal displacement and joint loadings were calculated for the intact wrist and for different simulated surgical procedures. The predicted total amount of force transmitted through the radio-lunate joint of the intact wrist averaged a 32% of the total radio-ulno-carpal joint load. Limited intercarpal fusions were found to reduce compressive loading at the radio-lunate joint by no more than 15% of the original load. Capitate shortening was successful in relieving radio-lunate forces, however, it dramatically overloaded the adjacent scapho-trapezial and triquetral-hamate joints. By contrast, a 4 mm lengthening of the ulna (or shortening of the radius) resulted in a 45% reduction of radio-lunate load with only moderate changes in force at the midcarpal and radio-scaphoid joints. On the basis of this study, radial shortening or ulnar lengthening significantly unload the lunate and are rationale procedures in the treatment of Kienböck's disease. Limitations regarding direct clinical application of this mathematical model are also discussed.

Three cases of syndactyly, polydactyly, and hypoplastic triphalangeal thumb: (Haas's malformation)

Three cases of a complex malformation of the hand involving syndactyly, polydactyly, and hypoplastic triphalangeal thumb are presented. In all three patients, six metacarpal bones and hypoplasticity of the thenar muscles were present. In one patient, both hands, except the most radial digits of the left hand, were completely fused by soft webs as reported by Haas and Ofodile. In two other patients, the extent of the webs differed from Haas's case, but one of them was similar to Ofodile's first case. In all instances the supernumerary digit had a triphalangeal configuration and the thenar muscles were hypoplastic, often associated with some degree of webbing.

Excessive radial shortening in Kienböck's disease

Two patients with Kienböck's disease who had been treated by radial shortening developed ulnar wrist pain post-operatively due to excessive radial shortening. In both cases, ulnar shortening was required to improve symptoms and function. Excessive radial shortening can cause ulnar wrist pain and compromise the improvement of grip strength and range of motion of the wrist.

Excessive radial shortening in Kienböck's disease

Two patients with Kienböck's disease who had been treated by radial shortening developed ulnar wrist pain post-operatively due to excessive radial shortening. In both cases, ulnar shortening was required to improve symptoms and function. Excessive radial shortening can cause ulnar wrist pain and compromise the improvement of grip strength and range of motion of the wrist.

Three-dimensional CT imaging for wrist disorders

Three-dimensional CT imaging of the wrist was performed in 20 patients: three with Kienböck's disease, 14 with fractures or dislocations of the carpal bones, two with dislocation of the distal radio-ulnar joint and one with an intra-articular fracture of distal radius. These images were compared with those of plain radiographs and computed tomography. With the exception of two cases of distal radio-ulnar joint dislocation and one case of hamate body fracture, three-dimensional CT imaging was helpful in detecting the displacement of the fracture and in determining the location and the direction of the displaced carpal bone. Furthermore, the presence of small fragments could be observed more easily in the three-dimensional CT image. Three-dimensional CT imaging provides a great deal of information that cannot be obtained by conventional radiographs or CT images even at their present stage of technical development.

Nonoperative treatment of camptodactyly

Twenty-four patients with camptodactyly of their small fingers were treated with a dynamic splint. Most of the patients could extend the proximal interphalangeal (PIP) joints within a few months by using the dynamic splint 24 hours a day. After almost full extension of the proximal interphalangeal joint was achieved, splinting for 8 hours a day produced good final results. However, after the splint was removed, contracture tended to recur. Although further studies are needed to determine the optimum termination of treatment, in our opinion it should be when the growth plate is closed, and longitudinal growth of the finger no longer occurs.

Reduction of the scaphoid fracture with DISI alignment

Eight cases of symptomatic malunion and nonunion of scaphoid fractures with dorsiflexed intercalated segment instability (DISI) alignment were treated by open reduction, anterior wedge-shaped bone grafting, and internal fixation using Herbert's screw. In four malunited fractures, osteotomy at the fracture line was done before the reduction. The DISI alignment was reduced by insertion of the Kirschner wire into the lunate and flexing it anteriorly. After the bone grafting to the anterior bony defect of the scaphoid, which was created by the Kirschner wire reduction, internal fixation was accomplished by the use of Herbert's screw. In all cases fusion was obtained within 4 months. Radiographic assessment indicated that the DISI alignment and the angulated scaphoid were corrected to achieve a nearly normal pattern. Pain, restricted motion of the wrist, and the grip strength were improved.