Kienböck's disease: preventing disease progression in early-stage disease.

Currently Kienböck's disease remains an 'unsolved' problem in hand surgery. Different factors have been associated with the avascular necrosis of the lunate. Mechanical, vascular and biological factors, alone or in combination, may have an influence in the aetiopathogenesis and determine the progress of the disease and even the results of the treatment. This is especially relevant in the early stages, in which conservative or surgical treatment may modify the natural history of the disease, maintaining the lunate structure and thus preserving the joint surfaces. There are multiple surgical treatments for Kienböck's disease in the early stages, before lunate collapse; each one is based on one of the possible factors that can cause avascular necrosis of the lunate. The objective is not only to treat symptoms but to prevent progression. This article is a review of the most frequent treatments used in the early stages and a personal view of the authors.Level of evidence: V.

Analysis of 3 Different Operative Techniques for Extra-articular Fractures of the Phalanges and Metacarpals.

Background: Several techniques have been described for treating metacarpal and phalangeal fractures. We sought to compare the 3 techniques most frequently used for extra-articular metacarpal and phalangeal fractures: plate screw (PS), Kirschner wire (KW), and retrograde intramedullary screw (RIS) fixation. We aimed to determine whether using an RIS provides better clinical outcomes than using either a PS or a KW fixation. Methods: We conducted a retrospective review of patients who underwent surgical treatment of metacarpal and phalangeal fractures from January 2011 to December 2017 in our department. Only patients with an acutely displaced short oblique or transverse extra-articular metacarpal or phalangeal fracture were included. Patients were classified into 3 groups depending on the treatment they received: PS, KW, or RIS fixation. The duration of each procedure was recorded. Clinical assessments included measuring total active motion (TAM), grip strength, and an evaluation of plain radiographs through to ultimate healing. A Disabilities of the Arm, Shoulder and Hand (QuickDASH) score was collected on all patients. Data were analyzed by analysis of variance or Kruskal-Wallis rank test, as indicated. Results: A total of 253 fractures (202 metacarpal and 51 phalangeal) in 230 patients were included in analysis. In all, 135 fractures (53.3%) underwent PS fixation; 53 (20.9%), KW fixation; and 65 (25.6%), RIS fixation. In the KW fixation group, Bouquet pinning was performed for metacarpal fractures and cross pinning for phalangeal fractures. When more than 1 fracture coexisted in the same patient, they were considered separate instances. No differences among the 3 groups were observed when evaluating mean time to radiological union, grip strength, TAM, or QuickDASH score. Mean surgery time was significantly shorter with KW (20 minutes) and RIS (25 minutes), than with PS (32 minutes). Mean return to work or routine activities time was significantly less in the RIS (7.8 weeks) group than in the PS and KW groups (8.3 and 9.2 weeks, respectively). Conclusions: Surgical treatment is recommended in patients with unstable metacarpal and phalangeal fractures. The use of RIS was associated with shorter mean surgery duration and return to work times than PS and KW, respectively.

Trigger Digit Incidence After Carpal Tunnel Release: Reconstruction in Elongated Position Versus Traditional Carpal Tunnel Release.

Background: The development of trigger digit after carpal tunnel syndrome release surgery has been widely reported. Lluch described reconstruction of the flexor retinaculum in elongated position to prevent such complication. Methods: We conducted a retrospective review to determine whether patients who undergo reconstruction in elongated position of the flexor retinaculum have a lower incidence of trigger digit postoperatively. In total, 1050 patients were included, 865 of whom had undergone traditional carpal tunnel release and 185 flexor retinaculum reconstruction. Results: No differences were found in the incidence of trigger digit after surgery (8.7% of the patients who underwent traditional release vs 11.9% in the reconstruction group). Neither difference was found when comparing mean time with the development of trigger digit. Conclusions: In the absence of randomized long-term studies comparing traditional release and reconstruction in elongated position after carpal tunnel release, given our results, we see no reason to favor reconstruction over standard carpal tunnel release as a means to prevent postoperative triggering of digits.

Kinetic dysfunction of the wrist with chronic scapholunate dissociation. A cadaver study.

BACKGROUND: Most laboratory studies investigating scapholunate dissociations are based on normal cadaver arms with serially sectioned ligaments. It is assumed that the kinetic behavior of a ligament-sectioned wrist is similar to a scapholunate dissociation. We tested five cadaver wrists with real injuries. The goal of this research was to evaluate the biomechanical behavior of scapholunate advanced collapse wrists compared to an experimental group with simulated injuries. METHODS: Using a magnetic 6-degree of freedom motion tracking device, changes in scaphoid alignment induced by isometric loading 5 wrist motor tendons in two groups of specimens were monitored. Twelve fresh cadaver wrists in which scapholunate injury was simulated by sectioning the scapholunate ligament were compared to 5 arms with chronic scapholunate dissociation. FINDINGS: The behavior of the scaphoid is the same in both groups, but the magnitude of displacement is greater in chronic scapholunate dissociation wrists, although not statistically significant. The extensor carpi ulnaris is the only muscle that provokes scaphoid pronation; all other muscles induce its supination. INTERPRETATION: Different factors may play a role in the amount of scaphoid rotation observed in wrists with chronic scapholunate dissociation. Ligament sectioning alone in the experimental setup can only partially replicate the behavior of real scapholunate dissociations. The extensor carpi ulnaris has a major role in destabilizing scapholunate advanced collapse wrists; therefore, isometric contraction of this muscle should be avoided in the conservative treatment. The experimental setup designed is useful to evaluate the biomechanical behavior of the carpus under traction load.

Trapeziometacarpal Ligaments Biomechanical Study: Implications in Arthroscopy.

Purpose In the presence of early osteoarthritis, changes to the trapeziometacarpal joint (TMJ) often result in pain and is associated with joint instability and a tendency of dorsoradial subluxation. In these instances, arthroscopy may be indicated to: (1) assess the extent of cartilage disease and the laxity of ligaments and to (2) treat TMJ instability. The purpose of our study was to biomechanically analyze which ligaments are the primary stabilizers of the TMJ. Methods Overall, 11 fresh-frozen human cadaver specimens were dissected and attached to a testing device with the thumb positioned in neutral abduction, neutral flexion, and neutral opposition. The four extrinsic and five intrinsic muscle tendons acting on the TMJ were simultaneously loaded with weights proportional to their physiological cross-sectional area. The dorsal, volar, and ulnar groups of ligaments were dissected. A motion-tracking device, FasTrak (Polhemus Inc., Colchester, VT), was used to study the spatial position of the base of the first metacarpal bone (MC1), before and after random sectioning of each of the ligaments. Statistical analysis of the MC1 translation along the transverse XY plane was performed using one-way analysis of variance and a paired t-test, with a significance level of p < 0.05. Results After isolated sectioning of the volar or the ulnar ligaments, the MC1 moved dorsoradially with an average of 0.150 mm (standard deviation [SD]: 0.072) and 0.064 mm (SD: 0.301), respectively. By contrast, the destabilization of the MC1 after sectioning of the dorsal ligaments was substantially larger (0.523 mm; SD: 0.0512; p = 0.004). Conclusion Sectioning of the dorsal ligament group resulted in the greatest dorsoradial translation of the MC1. Consequently, the dorsal ligaments may be regarded as the primary TMJ stabilizers. Clinical Relevance This study suggests that stabilizing arthroscopic shrinkage of the TMJ should be targeted toward the dorsal TMJ ligaments.

Role of the extensor carpi ulnaris in the stabilization of the lunotriquetral joint. An experimental study.

STUDY DESIGN: Experimental laboratory-based research in biomechanics. INTRODUCTION: The mechanisms by which some lunotriquetral (LTq) ligament disruptions remain stable are not known. PURPOSE OF THE STUDY: To investigate the contribution of muscles in preventing carpal destabilization when the LTq ligaments are torn. METHODS: Ten fresh cadaver wrists, set vertical in a jig, were isometrically loaded through five wrist motor tendons. Changes in carpal alignment secondary to the application of loads were monitored by a Fastrak™ electromagnetic motion tracking device, before and after sectioning the LTq ligaments. RESULTS: After LTq ligaments sectioning, wrist loading forced the triquetrum into flexion (5.4° average) and supination (2.9 ). The only muscle capable of extending and pronating the collapsed triquetrum was the extensor carpi ulnaris (ECU). CONCLUSIONS: Inadequate ECU muscle function is an important destabilizing factor in LTq deficient wrists. Dynamic LTq instabilities may benefit from proprioceptionally training the ECU muscle, while avoiding carpal supination torques.